Who's left in the E6 biz?

Robert Vervoordt wrote:

On Mon, 20 Sep 2004 00:40:48 GMT, Donald Qualls
wrote:

Surely, but with Fomapan R, the negative is impossible to see because of
the (not yet removed) silver AH layer. If I develop Fomapan R in, say,
HC-110 Dilution B, I'll get a solid black strip of film.


Oooh, nasty! That Is quite a bit different from all the other BW
reversal films I encountered or heard of.

Exactly. Fomapan R is a dedicated movie stock, completely unrelated to
Foma's still film emulsions, AFAIK. Silver AH is apparently common in
color movie stocks that will be bleached in processing, but Fomapan is
the only B&W stock I've heard of that has it.

In a reversal
process, the bleach step would remove that layer. I'm unclear on what
you're saying happens in the developer (or first dev, for reversal).


I got that wrong, alright. Still, if the AH layer is very fine
colloidal Silver, it might be capable of removal during development in
a normal negative developer with some small amount of Thiocyanate
added. Such layers are "usually" susceptable to quick dissolution by
Thiocyanate long before it would attack any Silver Halides or even
developed Silver grains. A quick test would reveal if that were so.

Yeah. "Might be."

As you say, a quick test would show this, though I'd be tempted to try
judicious overfixing first; I've acheived visible bleaching using rapid
fixer with additional acetic acid added (though it took a long soak),
and would expect to get results on a silver AH layer more quickly.

More on that question below.


; the
thiocyanate (or similar) sounds necessary to reversal processing of any
film (as a fog control for the final positive?),


No, as a method of clearing extremely fine Silver from the highlights.
This is only a consideration for reversal processing and the nead for
very clear highlights in projection. When it comes to negatives and
printing, the slight density in the highlights may be actually an
advantage as it would limit the range of negative densities slightly.

Okay, fine silver in the highlights (after reversal) *is* fog, is it
not?


No. it's not fog. it's much more severe. As experienced by you, with
Fomapan R it's a completely developed layer of colloidal Silver, and
not something an anti foggant would be likely to have any significant
effect upon.

Okay, like very severe fog, then -- somwhere, if I didn't toss it when
packing for my move, I have a roll of old Kodachrome II (expiry 1964)
that I found in a camera and developed in Diafine; it came out solid
black, but I was able to bleach in acidified rapid fixer (see above)
enough to verify that there were no salvageable images on the film. I
don't think that film had a silver AH layer, though.


Okay, I never saw that list before, but it was my understanding that
(for instance) Plus-X Reversal was pretty much the same as Plus-X Neg
and Plus-X Pan still photo emulsion, but movie films were expected to be
processed to much lower contrast, which lowers speed.


Yep. That's why the Tri-X emulsion, which is named Double-X Negative
in motion picture use, is rated at 200 or 250 in daylight. Ilford has
or had a Mark 5, which was the same as HP-5. I used both in still
camera work and found them to be the same as the still versions when
developed as suc.

I've seen pictures shot with Double-X Negative in 35 mm, they're much
grainier than Tri-X and were shot at EI 200 -- and no, this is not Super
XX from the 1950s, it was 35 mm movie stock bulk loaded into cassettes.
I don't think Double-X Negative is quite the same as Tri-X.

and if I want/need EI 400 for a
subminiature camera, I'm stuck slitting 400TX or TMY (or similar Ilford
or Agfa products); none of the existing movie stocks will give EI above
200 in D-76.


Four-X reversal is actually the same as Tri-x or Double-X negative.
If developed as you would Tri-X Pan, it will have the same speed and
image chacteristics.

Unfortunately, Four-X Reversal isn't available in 16 mm, as far as I've
been able to tell; it might not be available at all any more. I can get
Double-X Negative, I think, which you're saying is the same stuff (but
if it's the same, why doesn't Kodak simply recommend different EI for
shooting as negative or positive instead of marketing as two different
films?).

.
Or does the above equivalence of Tri-X Pan with Double-X

Negative movie film suggest that the Double-X Neg is subject to speed
reduction by the low contrast movie negative development, and just gets
back to Tri-X speed with the "boost" of reversal?


Not exactly, Double-X or Tri-X will get to the speed of Four-X
reversal with reversal processing. When processed as a still
negative, the extra processing time will boost speed and contrast over
the results obtained in the motion picture formulae's time and temp,
as well as its different formulation.

Okay, so Tri-X Pan still film is the same as Four-X Reversal? Then the
Tri-X (ISO 400) gets downrated to EI 200 for movie negative processing
due to lower contrast development, and uprated back to EI 400 for
reversal -- doesn't sound like I'm getting a speed boost with reversal,
just getting back what the movie process loses (unless I'd get another
stop with processing as a reversed still).

This is all very confusing, and none of it would be necessary if I could
just buy ISO 400 B&W negative film in 16 mm (preferably Tri-X Pan, aka
400TX, which gives a very usable EI 1600 without much if any grain
increase when developed in Diafine).


Get some 16mm Double-X and treat it the same as your still fim, tri-X,
and all will be as you desire.

Okay, I might have to see if I can't land a roll of that stuff. It was,
IIRC, around $25 for 200 feet, which is quite attractive (other than the
daunting prospect of having 99 rolls left over if I don't like it).
Won't be money for experimentation for a while, though; this move just
keeps sucking up more and more money...

Okay, clarify this for me -- if something dissolves metallic silver, to
me, that's a bleach; it'll dissolve image silver and latent image specks
just as readily as it will remove a silver AH layer. As a result, it
seems it ought to eat up shadows in a negative and reduce speed, both by
killing the weakest/sparsest latent image specks before they can be
developed, and by dissolving away the least dense areas of the image
just as it dissolves the AH silver.


The AH Silver is of a different form than the Silver that forms the
image. It is already reduced, and blackened. That is how it works as
an AH layer during exposure. The Thiocyante can attack it
immediately, as it is much more finely formed than any Halide or
Silver grain that will form the image. If this were not the case, it
wouldn't work the way it does in a reversal process.

Developed image silver is reduced, as is the metallic silver that forms
a latent image speck -- and I'd argue that a latent image speck, a tiny
fraction of a halide grain, is smaller than the particles of colloidal
silver in the AH layer. In a reversal process, the bleach step that
removes the silver image (either from the first dev, or from both dev
steps, depending on whether you're using a silver-based B&W or a dye
based color film) also removes the AH layer.

From my reading on reversing conventional B&W still films, thiocyanate,
thiosulfate, etc. in the first dev is to remove "stubborn" halide
(undevelopable even after maximum exposure) from the most exposed areas
to prevent fogged highlights after reversal exposure and redevelopment.
This is not at all the same as bleaching away the metallic silver of
the AH layer. A "silver solvent", at least as the term is usually used
relative to development, is a halide solvent, not a metallic silver
solvent; sulfite, thiosulfate, etc. are silver solvents, and their
intended function (at least in that regard, since sulfite does so many
other things) is generally reduction of grain by reducing halide grain
size and preventing excessive growth of silver grains. Thiocyanate,
IIRC, is a true bleach similar to ferricyanides, dichromates,
permanganates, etc.; that is, it is capable of reacting with and
dissolving or rehalogentating reduced silver.

Silver is silver -- chemically, if you dissolve silver metal one place,
you'll dissolve it anywhere else in the same bath, and dissolving silver
*has to* cost you shadow speed in the negative.


No, it would do that in a reversal developer, as well, if that were
so. You can safely assume that since it works in a reversal first
developer, it can work in a negative developer in the same fashio.
While there are differences in the energy of reversal and negative
developers, they are not enough to make much difference. I did it and
it worked with something I used.

What film have you developed with a thiocyanate-added B&W developer that
had a silver AH layer? What developer did you use, and how much
thiocyanate did you add? Knowing this could save me many hours of
experimentation...

Single perf won't work?

Single perf works fine (the Minolta 16 advance system doesn't care about
perforations; it will use single, double, or unperfed, though the later
12x17 frame MGs and QT require single perf loaded with the perforations
toward the cassette bridge, or unperfed, to avoid perforations intruding
on image area).

However, a film sold for Double 8 (double perf, finer pitch perforation
than 16 mm single perf) typically comes in short camera rolls (25 feet,
which is shot, reloaded from the other end, and shot again, then split
after development and spliced to yield 50 feet of 8 mm film) compared to
the 16 mm that comes in 100 or 200 foot lengths.

But even J and C Photography can't seem to verify that
Fomapan R can be developed to a negative -- I asked them about it a
couple months ago, got an answer suggesting use of E-6 bleach, and when
I asked how to avoid bleaching the image as well as the AH layer, never
got a reply (they were waiting for information from Foma, and seemingly
never got it). The E-6 bleach would be perfect for reversal processing
-- but not much use if you want a negative.


I know that you're up to the experiment, just sacrifice a roll or two
and see if it suits you. Thiocyante should be easy to obtain.

When I have time, space, and money to experiment again, I'll probably do
just that; as you say, I can get thiocyanate from Photographer's
Formulary, and $8 (plus shipping, but I'd probably piggyback that with
an order for Classic 400 in 120, which I've been meaning to get anyway)
will get me enough film for a dozen rolls, should be plenty to
experiment on.

I'm smiling just thinking of the commotion at Foma hunting down the
one guy who can answer your questions.

Yeah, which is silly given that they have miles of the film around, and
a warehouse full of chemicals; they should be able to simply shoot a
short length and process it to verify.

--
I may be a scwewy wabbit, but I'm not going to Alcatwaz!
-- E. J. Fudd, 1954

Donald Qualls, aka The Silent Observer
Lathe Building Pages http://silent1.home.netcom.com/HomebuiltLathe.htm
Speedway 7x12 Lathe Pages http://silent1.home.netcom.com/my7x12.htm

Opinions expressed are my own -- take them for what they're worth
and don't expect them to be perfect.

On Mon, 20 Sep 2004 11:23:02 GMT, Donald Qualls
wrote:

Robert Vervoordt wrote:

On Mon, 20 Sep 2004 00:40:48 GMT, Donald Qualls
wrote:

Surely, but with Fomapan R, the negative is impossible to see because of
the (not yet removed) silver AH layer. If I develop Fomapan R in, say,
HC-110 Dilution B, I'll get a solid black strip of film.


Oooh, nasty! That Is quite a bit different from all the other BW
reversal films I encountered or heard of.

Exactly. Fomapan R is a dedicated movie stock, completely unrelated to
Foma's still film emulsions, AFAIK. Silver AH is apparently common in
color movie stocks that will be bleached in processing, but Fomapan is
the only B&W stock I've heard of that has it.

In a reversal
process, the bleach step would remove that layer. I'm unclear on what
you're saying happens in the developer (or first dev, for reversal).


I got that wrong, alright. Still, if the AH layer is very fine
colloidal Silver, it might be capable of removal during development in
a normal negative developer with some small amount of Thiocyanate
added. Such layers are "usually" susceptable to quick dissolution by
Thiocyanate long before it would attack any Silver Halides or even
developed Silver grains. A quick test would reveal if that were so.

Yeah. "Might be."

As you say, a quick test would show this, though I'd be tempted to try
judicious overfixing first; I've acheived visible bleaching using rapid
fixer with additional acetic acid added (though it took a long soak),
and would expect to get results on a silver AH layer more quickly.

Boy. it had better be judicious, as raoid fixers are known to begin
bleaching silver very soon after the time is extended. This is
especially so with papers, but there have been some reports of it
affecting film as well. If it works quickly enough on the Silver AH
layer, that may be all you'll need. Still the addition of Thiocyanate
to the developer seems more elegant, as it cuts out that extra work
you described.

More on that question below.


; the
thiocyanate (or similar) sounds necessary to reversal processing of any
film (as a fog control for the final positive?),


No, as a method of clearing extremely fine Silver from the highlights.
This is only a consideration for reversal processing and the nead for
very clear highlights in projection. When it comes to negatives and
printing, the slight density in the highlights may be actually an
advantage as it would limit the range of negative densities slightly.

Okay, fine silver in the highlights (after reversal) *is* fog, is it
not?

Ah, the semantics! Without continuing with refining terms, possibly.
Let's just keep focussed on getting results that will serve your
needs.


No. it's not fog. it's much more severe. As experienced by you, with
Fomapan R it's a completely developed layer of colloidal Silver, and
not something an anti foggant would be likely to have any significant
effect upon.

Okay, like very severe fog, then -- somwhere, if I didn't toss it when
packing for my move, I have a roll of old Kodachrome II (expiry 1964)
that I found in a camera and developed in Diafine; it came out solid
black, but I was able to bleach in acidified rapid fixer (see above)
enough to verify that there were no salvageable images on the film. I
don't think that film had a silver AH layer, though.

It doesn't. It has a black backing on the base surface of the film
that has to be removed prior to development in an alkaline bath
folloed by a wsh, at least in machine processing. This is the same
black gunky stuff found in Eastmans motion picture stocks.

When using short ends of MP color film, I, and others, just wash it
off after stopping development. I takes a little scrubbing, but
doesn't affect the chemical processes. It is just some plasticky
stuff that can even be left on until after fixing without a penalty,
save making your reels look dirty. Get it off before washing, though
and don't let it dry on the film at all.

Now, since this is not a Silver AH, there is no need for any chemical
removal. It won't work. What happened with your Kodachrome may have
been that you were mislead by the RemJet backing that remained almost
intact on the prodessed film. Putting it in the rapid fixer then may
have been more than the weak imagees that were developed in the
emulsion could withstand, and they were bleaced out. How you got rid
of the rem jet is beyond me, unless the film was completely fogged and
the RemJet AH backing got removed by the Carbonate B bath; this does
happen in my experience, though I have almost always noticed some
residue that needed wiping. I have done this so often, that I am
primed to look for the slightest remnant.

There are too many wild cards in this instance to rely on it for
guidance.


Okay, I never saw that list before, but it was my understanding that
(for instance) Plus-X Reversal was pretty much the same as Plus-X Neg
and Plus-X Pan still photo emulsion, but movie films were expected to be
processed to much lower contrast, which lowers speed.

I think you snipped something here. I thought I pointed to Plus-X
reversal being the same as Panatomic-X negative.

Movie film processing leads to lower contrast and speed for the same
emulsion compared to its development in the usual still fim
developers. MP requirements are for tonalty, sharpness and graininess
in that order.


Yep. That's why the Tri-X emulsion, which is named Double-X Negative
in motion picture use, is rated at 200 or 250 in daylight. Ilford has
or had a Mark 5, which was the same as HP-5. I used both in still
camera work and found them to be the same as the still versions when
developed as suc.

I've seen pictures shot with Double-X Negative in 35 mm, they're much
grainier than Tri-X and were shot at EI 200 -- and no, this is not Super
XX from the 1950s, it was 35 mm movie stock bulk loaded into cassettes.
I don't think Double-X Negative is quite the same as Tri-X.

That wasn't my experience at all. I used Double-X that had a known
and proper storage history, so I know that heat, radiation and age
were not factors in my use. I developed both in the same developer,
same tank, same time and temp and together, at once. If some of these
factors were different, that might be the reason for the difference in
the results you saw.

and if I want/need EI 400 for a
subminiature camera, I'm stuck slitting 400TX or TMY (or similar Ilford
or Agfa products); none of the existing movie stocks will give EI above
200 in D-76.


Four-X reversal is actually the same as Tri-x or Double-X negative.
If developed as you would Tri-X Pan, it will have the same speed and
image chacteristics.

Unfortunately, Four-X Reversal isn't available in 16 mm, as far as I've
been able to tell; it might not be available at all any more. I can get
Double-X Negative, I think, which you're saying is the same stuff (but
if it's the same, why doesn't Kodak simply recommend different EI for
shooting as negative or positive instead of marketing as two different
films?).

Yeah, why? I think the marketing guys had a big say here. There are
probably some differences in the overcoat and some other conditioning
additives, but, aside from the lack of an anticurl layer on the base
of XX, I haven't noticed any real difference.


.
Or does the above equivalence of Tri-X Pan with Double-X

Negative movie film suggest that the Double-X Neg is subject to speed
reduction by the low contrast movie negative development, and just gets
back to Tri-X speed with the "boost" of reversal?

Different applications, different results. Development to a higher
contrast in somewhat different formulae could well account for all the
difference. It gets back to Tri-X speed in D-76 with still film
develoment times.



Not exactly, Double-X or Tri-X will get to the speed of Four-X
reversal with reversal processing. When processed as a still
negative, the extra processing time will boost speed and contrast over
the results obtained in the motion picture formulae's time and temp,
as well as its different formulation.

Okay, so Tri-X Pan still film is the same as Four-X Reversal? Then the
Tri-X (ISO 400) gets downrated to EI 200 for movie negative processing
due to lower contrast development, and uprated back to EI 400 for
reversal -- doesn't sound like I'm getting a speed boost with reversal,
just getting back what the movie process loses (unless I'd get another
stop with processing as a reversed still).

The speed gain of reversal processing seems to be more pronounced the
slower the basic emulsion. It begins to taper off as the film's
basic, negative speed is increased.

Pan-X 1 2/3 stops
Plus-X 1 1/3 stops
XX 1 stop.

Don't forget, all the reversal processes, up to recently have had the
same first development applied to all the emulsions we are considering
here. And the results show great contrast boosts for the slower films.
The speed boost are reflective of that.

In still practice, we generally use shorter times in order to keep
pictorial results consistent. This would eliminate greater speed
differentials for the slow films.

This is all very confusing, and none of it would be necessary if I could
just buy ISO 400 B&W negative film in 16 mm (preferably Tri-X Pan, aka
400TX, which gives a very usable EI 1600 without much if any grain
increase when developed in Diafine).


Get some 16mm Double-X and treat it the same as your still fim, tri-X,
and all will be as you desire.

Okay, I might have to see if I can't land a roll of that stuff. It was,
IIRC, around $25 for 200 feet, which is quite attractive (other than the
daunting prospect of having 99 rolls left over if I don't like it).
Won't be money for experimentation for a while, though; this move just
keeps sucking up more and more money...

Oh, I hear you! I still haven't got a place to move to.

Hey, just spool of one roll at a time. If you don't like it, sell the
remaider as a short end for movie use/

Okay, clarify this for me -- if something dissolves metallic silver, to
me, that's a bleach; it'll dissolve image silver and latent image specks
just as readily as it will remove a silver AH layer. As a result, it
seems it ought to eat up shadows in a negative and reduce speed, both by
killing the weakest/sparsest latent image specks before they can be
developed, and by dissolving away the least dense areas of the image
just as it dissolves the AH silver.

The shadow densities are usually made up of the largest, most
resistant grains in the image; usually Iosdides. Highlights will
have a greater proportion of small, slower grains. That's why
Thiocyanate clears highlights and doesn't affect the rest of the image
in the time normally encountered in first development. Let it sit for
an hour or more and see what happens, though.


The AH Silver is of a different form than the Silver that forms the
image. It is already reduced, and blackened. That is how it works as
an AH layer during exposure. The Thiocyante can attack it
immediately, as it is much more finely formed than any Halide or
Silver grain that will form the image. If this were not the case, it
wouldn't work the way it does in a reversal process.

Developed image silver is reduced, as is the metallic silver that forms
a latent image speck -- and I'd argue that a latent image speck, a tiny
fraction of a halide grain, is smaller than the particles of colloidal
silver in the AH layer.

Colloidal silver is smallest.

In a reversal process, the bleach step that
removes the silver image (either from the first dev, or from both dev
steps, depending on whether you're using a silver-based B&W or a dye
based color film) also removes the AH layer.

Sure, if it hasn't been removed from the emulsion before, by a solvent
action, such as Thiocyanate. So, according to what you said, why
doesn;t this work with Fomapan? Was the film light stuck?

From my reading on reversing conventional B&W still films, thiocyanate,
thiosulfate, etc. in the first dev is to remove "stubborn" halide
(undevelopable even after maximum exposure) from the most exposed areas
to prevent fogged highlights after reversal exposure and redevelopment.

OK, then which Halides would be left? The smallest, which probably
never reached a threshold of exposure to make them developable.

This is not at all the same as bleaching away the metallic silver of
the AH layer.

I wouldn't say "not at all", as what is happening in both cases is
that the Thiocyanate is able to dissolve the smallest particles much
sooner than it can begin to have an effect on anything larger. It
also works on Colloidal particles and Chlorides before it can affect
the Bromides and Iododes which make up the majority of the rest of
the distribution. The Chlorides ar the Halides with the least
sensitivity to light.

A "silver solvent", at least as the term is usually used
relative to development, is a halide solvent, not a metallic silver
solvent;

That's to general and misses the differences in actions on the
different Halides and forms of Silver metal in the emulsion. See
above.

sulfite, thiosulfate, etc. are silver solvents, and their
intended function (at least in that regard, since sulfite does so many
other things) is generally reduction of grain by reducing halide grain
size and preventing excessive growth of silver grains.

Add fixing for Thiosulfate. That affects Halides long before it
affects Silver.

Thiocyanate,
IIRC, is a true bleach similar to ferricyanides, dichromates,
permanganates, etc.; that is, it is capable of reacting with and
dissolving or rehalogentating reduced silver.

No, it's more like Thiosulfate, in that it can "fix" film. It doesn't
blaech well, as it barfs on larger Halide grains and those with
Iodide.


Silver is silver -- chemically, if you dissolve silver metal one place,
you'll dissolve it anywhere else in the same bath, and dissolving silver
*has to* cost you shadow speed in the negative.

No, se info Iodides.


No, it would do that in a reversal developer, as well, if that were
so. You can safely assume that since it works in a reversal first
developer, it can work in a negative developer in the same fashio.
While there are differences in the energy of reversal and negative
developers, they are not enough to make much difference. I did it and
it worked with something I used.

What film have you developed with a thiocyanate-added B&W developer that
had a silver AH layer? What developer did you use, and how much
thiocyanate did you add? Knowing this could save me many hours of
experimentation...

Hmm, maybe I didn't. I can't recall any BW reversal or negative film
with aSilver AH layer. I must have been thinking of using Fujicolor
neg MP film in my speed boosting process that used first development
in a BW formula and rehalogenation to finish in the colr development
remaider of the process.

Single perf won't work?

Single perf works fine (the Minolta 16 advance system doesn't care about
perforations; it will use single, double, or unperfed, though the later
12x17 frame MGs and QT require single perf loaded with the perforations
toward the cassette bridge, or unperfed, to avoid perforations intruding
on image area).

However, a film sold for Double 8 (double perf, finer pitch perforation
than 16 mm single perf) typically comes in short camera rolls (25 feet,
which is shot, reloaded from the other end, and shot again, then split
after development and spliced to yield 50 feet of 8 mm film) compared to
the 16 mm that comes in 100 or 200 foot lengths.

But even J and C Photography can't seem to verify that
Fomapan R can be developed to a negative -- I asked them about it a
couple months ago, got an answer suggesting use of E-6 bleach, and when
I asked how to avoid bleaching the image as well as the AH layer, never
got a reply (they were waiting for information from Foma, and seemingly
never got it). The E-6 bleach would be perfect for reversal processing
-- but not much use if you want a negative.


I know that you're up to the experiment, just sacrifice a roll or two
and see if it suits you. Thiocyante should be easy to obtain.

When I have time, space, and money to experiment again, I'll probably do
just that; as you say, I can get thiocyanate from Photographer's
Formulary, and $8 (plus shipping, but I'd probably piggyback that with
an order for Classic 400 in 120, which I've been meaning to get anyway)
will get me enough film for a dozen rolls, should be plenty to
experiment on.

I'm smiling just thinking of the commotion at Foma hunting down the
one guy who can answer your questions.

Yeah, which is silly given that they have miles of the film around, and
a warehouse full of chemicals; they should be able to simply shoot a
short length and process it to verify.

You expect that of marketing me?



Robert Vervoordt, MFA

On Mon, 20 Sep 2004 11:23:02 GMT, Donald Qualls
wrote:

Robert Vervoordt wrote:

On Mon, 20 Sep 2004 00:40:48 GMT, Donald Qualls
wrote:

Surely, but with Fomapan R, the negative is impossible to see because of
the (not yet removed) silver AH layer. If I develop Fomapan R in, say,
HC-110 Dilution B, I'll get a solid black strip of film.


Oooh, nasty! That Is quite a bit different from all the other BW
reversal films I encountered or heard of.

Exactly. Fomapan R is a dedicated movie stock, completely unrelated to
Foma's still film emulsions, AFAIK. Silver AH is apparently common in
color movie stocks that will be bleached in processing, but Fomapan is
the only B&W stock I've heard of that has it.

In a reversal
process, the bleach step would remove that layer. I'm unclear on what
you're saying happens in the developer (or first dev, for reversal).


I got that wrong, alright. Still, if the AH layer is very fine
colloidal Silver, it might be capable of removal during development in
a normal negative developer with some small amount of Thiocyanate
added. Such layers are "usually" susceptable to quick dissolution by
Thiocyanate long before it would attack any Silver Halides or even
developed Silver grains. A quick test would reveal if that were so.

Yeah. "Might be."

As you say, a quick test would show this, though I'd be tempted to try
judicious overfixing first; I've acheived visible bleaching using rapid
fixer with additional acetic acid added (though it took a long soak),
and would expect to get results on a silver AH layer more quickly.

Boy. it had better be judicious, as raoid fixers are known to begin
bleaching silver very soon after the time is extended. This is
especially so with papers, but there have been some reports of it
affecting film as well. If it works quickly enough on the Silver AH
layer, that may be all you'll need. Still the addition of Thiocyanate
to the developer seems more elegant, as it cuts out that extra work
you described.

More on that question below.


; the
thiocyanate (or similar) sounds necessary to reversal processing of any
film (as a fog control for the final positive?),


No, as a method of clearing extremely fine Silver from the highlights.
This is only a consideration for reversal processing and the nead for
very clear highlights in projection. When it comes to negatives and
printing, the slight density in the highlights may be actually an
advantage as it would limit the range of negative densities slightly.

Okay, fine silver in the highlights (after reversal) *is* fog, is it
not?

Ah, the semantics! Without continuing with refining terms, possibly.
Let's just keep focussed on getting results that will serve your
needs.


No. it's not fog. it's much more severe. As experienced by you, with
Fomapan R it's a completely developed layer of colloidal Silver, and
not something an anti foggant would be likely to have any significant
effect upon.

Okay, like very severe fog, then -- somwhere, if I didn't toss it when
packing for my move, I have a roll of old Kodachrome II (expiry 1964)
that I found in a camera and developed in Diafine; it came out solid
black, but I was able to bleach in acidified rapid fixer (see above)
enough to verify that there were no salvageable images on the film. I
don't think that film had a silver AH layer, though.

It doesn't. It has a black backing on the base surface of the film
that has to be removed prior to development in an alkaline bath
folloed by a wsh, at least in machine processing. This is the same
black gunky stuff found in Eastmans motion picture stocks.

When using short ends of MP color film, I, and others, just wash it
off after stopping development. I takes a little scrubbing, but
doesn't affect the chemical processes. It is just some plasticky
stuff that can even be left on until after fixing without a penalty,
save making your reels look dirty. Get it off before washing, though
and don't let it dry on the film at all.

Now, since this is not a Silver AH, there is no need for any chemical
removal. It won't work. What happened with your Kodachrome may have
been that you were mislead by the RemJet backing that remained almost
intact on the prodessed film. Putting it in the rapid fixer then may
have been more than the weak imagees that were developed in the
emulsion could withstand, and they were bleaced out. How you got rid
of the rem jet is beyond me, unless the film was completely fogged and
the RemJet AH backing got removed by the Carbonate B bath; this does
happen in my experience, though I have almost always noticed some
residue that needed wiping. I have done this so often, that I am
primed to look for the slightest remnant.

There are too many wild cards in this instance to rely on it for
guidance.


Okay, I never saw that list before, but it was my understanding that
(for instance) Plus-X Reversal was pretty much the same as Plus-X Neg
and Plus-X Pan still photo emulsion, but movie films were expected to be
processed to much lower contrast, which lowers speed.

I think you snipped something here. I thought I pointed to Plus-X
reversal being the same as Panatomic-X negative.

Movie film processing leads to lower contrast and speed for the same
emulsion compared to its development in the usual still fim
developers. MP requirements are for tonalty, sharpness and graininess
in that order.


Yep. That's why the Tri-X emulsion, which is named Double-X Negative
in motion picture use, is rated at 200 or 250 in daylight. Ilford has
or had a Mark 5, which was the same as HP-5. I used both in still
camera work and found them to be the same as the still versions when
developed as suc.

I've seen pictures shot with Double-X Negative in 35 mm, they're much
grainier than Tri-X and were shot at EI 200 -- and no, this is not Super
XX from the 1950s, it was 35 mm movie stock bulk loaded into cassettes.
I don't think Double-X Negative is quite the same as Tri-X.

That wasn't my experience at all. I used Double-X that had a known
and proper storage history, so I know that heat, radiation and age
were not factors in my use. I developed both in the same developer,
same tank, same time and temp and together, at once. If some of these
factors were different, that might be the reason for the difference in
the results you saw.

and if I want/need EI 400 for a
subminiature camera, I'm stuck slitting 400TX or TMY (or similar Ilford
or Agfa products); none of the existing movie stocks will give EI above
200 in D-76.


Four-X reversal is actually the same as Tri-x or Double-X negative.
If developed as you would Tri-X Pan, it will have the same speed and
image chacteristics.

Unfortunately, Four-X Reversal isn't available in 16 mm, as far as I've
been able to tell; it might not be available at all any more. I can get
Double-X Negative, I think, which you're saying is the same stuff (but
if it's the same, why doesn't Kodak simply recommend different EI for
shooting as negative or positive instead of marketing as two different
films?).

Yeah, why? I think the marketing guys had a big say here. There are
probably some differences in the overcoat and some other conditioning
additives, but, aside from the lack of an anticurl layer on the base
of XX, I haven't noticed any real difference.


.
Or does the above equivalence of Tri-X Pan with Double-X

Negative movie film suggest that the Double-X Neg is subject to speed
reduction by the low contrast movie negative development, and just gets
back to Tri-X speed with the "boost" of reversal?

Different applications, different results. Development to a higher
contrast in somewhat different formulae could well account for all the
difference. It gets back to Tri-X speed in D-76 with still film
develoment times.



Not exactly, Double-X or Tri-X will get to the speed of Four-X
reversal with reversal processing. When processed as a still
negative, the extra processing time will boost speed and contrast over
the results obtained in the motion picture formulae's time and temp,
as well as its different formulation.

Okay, so Tri-X Pan still film is the same as Four-X Reversal? Then the
Tri-X (ISO 400) gets downrated to EI 200 for movie negative processing
due to lower contrast development, and uprated back to EI 400 for
reversal -- doesn't sound like I'm getting a speed boost with reversal,
just getting back what the movie process loses (unless I'd get another
stop with processing as a reversed still).

The speed gain of reversal processing seems to be more pronounced the
slower the basic emulsion. It begins to taper off as the film's
basic, negative speed is increased.

Pan-X 1 2/3 stops
Plus-X 1 1/3 stops
XX 1 stop.

Don't forget, all the reversal processes, up to recently have had the
same first development applied to all the emulsions we are considering
here. And the results show great contrast boosts for the slower films.
The speed boost are reflective of that.

In still practice, we generally use shorter times in order to keep
pictorial results consistent. This would eliminate greater speed
differentials for the slow films.

This is all very confusing, and none of it would be necessary if I could
just buy ISO 400 B&W negative film in 16 mm (preferably Tri-X Pan, aka
400TX, which gives a very usable EI 1600 without much if any grain
increase when developed in Diafine).


Get some 16mm Double-X and treat it the same as your still fim, tri-X,
and all will be as you desire.

Okay, I might have to see if I can't land a roll of that stuff. It was,
IIRC, around $25 for 200 feet, which is quite attractive (other than the
daunting prospect of having 99 rolls left over if I don't like it).
Won't be money for experimentation for a while, though; this move just
keeps sucking up more and more money...

Oh, I hear you! I still haven't got a place to move to.

Hey, just spool of one roll at a time. If you don't like it, sell the
remaider as a short end for movie use/

Okay, clarify this for me -- if something dissolves metallic silver, to
me, that's a bleach; it'll dissolve image silver and latent image specks
just as readily as it will remove a silver AH layer. As a result, it
seems it ought to eat up shadows in a negative and reduce speed, both by
killing the weakest/sparsest latent image specks before they can be
developed, and by dissolving away the least dense areas of the image
just as it dissolves the AH silver.

The shadow densities are usually made up of the largest, most
resistant grains in the image; usually Iosdides. Highlights will
have a greater proportion of small, slower grains. That's why
Thiocyanate clears highlights and doesn't affect the rest of the image
in the time normally encountered in first development. Let it sit for
an hour or more and see what happens, though.


The AH Silver is of a different form than the Silver that forms the
image. It is already reduced, and blackened. That is how it works as
an AH layer during exposure. The Thiocyante can attack it
immediately, as it is much more finely formed than any Halide or
Silver grain that will form the image. If this were not the case, it
wouldn't work the way it does in a reversal process.

Developed image silver is reduced, as is the metallic silver that forms
a latent image speck -- and I'd argue that a latent image speck, a tiny
fraction of a halide grain, is smaller than the particles of colloidal
silver in the AH layer.

Colloidal silver is smallest.

In a reversal process, the bleach step that
removes the silver image (either from the first dev, or from both dev
steps, depending on whether you're using a silver-based B&W or a dye
based color film) also removes the AH layer.

Sure, if it hasn't been removed from the emulsion before, by a solvent
action, such as Thiocyanate. So, according to what you said, why
doesn;t this work with Fomapan? Was the film light stuck?

From my reading on reversing conventional B&W still films, thiocyanate,
thiosulfate, etc. in the first dev is to remove "stubborn" halide
(undevelopable even after maximum exposure) from the most exposed areas
to prevent fogged highlights after reversal exposure and redevelopment.

OK, then which Halides would be left? The smallest, which probably
never reached a threshold of exposure to make them developable.

This is not at all the same as bleaching away the metallic silver of
the AH layer.

I wouldn't say "not at all", as what is happening in both cases is
that the Thiocyanate is able to dissolve the smallest particles much
sooner than it can begin to have an effect on anything larger. It
also works on Colloidal particles and Chlorides before it can affect
the Bromides and Iododes which make up the majority of the rest of
the distribution. The Chlorides ar the Halides with the least
sensitivity to light.

A "silver solvent", at least as the term is usually used
relative to development, is a halide solvent, not a metallic silver
solvent;

That's to general and misses the differences in actions on the
different Halides and forms of Silver metal in the emulsion. See
above.

sulfite, thiosulfate, etc. are silver solvents, and their
intended function (at least in that regard, since sulfite does so many
other things) is generally reduction of grain by reducing halide grain
size and preventing excessive growth of silver grains.

Add fixing for Thiosulfate. That affects Halides long before it
affects Silver.

Thiocyanate,
IIRC, is a true bleach similar to ferricyanides, dichromates,
permanganates, etc.; that is, it is capable of reacting with and
dissolving or rehalogentating reduced silver.

No, it's more like Thiosulfate, in that it can "fix" film. It doesn't
blaech well, as it barfs on larger Halide grains and those with
Iodide.


Silver is silver -- chemically, if you dissolve silver metal one place,
you'll dissolve it anywhere else in the same bath, and dissolving silver
*has to* cost you shadow speed in the negative.

No, se info Iodides.


No, it would do that in a reversal developer, as well, if that were
so. You can safely assume that since it works in a reversal first
developer, it can work in a negative developer in the same fashio.
While there are differences in the energy of reversal and negative
developers, they are not enough to make much difference. I did it and
it worked with something I used.

What film have you developed with a thiocyanate-added B&W developer that
had a silver AH layer? What developer did you use, and how much
thiocyanate did you add? Knowing this could save me many hours of
experimentation...

Hmm, maybe I didn't. I can't recall any BW reversal or negative film
with aSilver AH layer. I must have been thinking of using Fujicolor
neg MP film in my speed boosting process that used first development
in a BW formula and rehalogenation to finish in the colr development
remaider of the process.

Single perf won't work?

Single perf works fine (the Minolta 16 advance system doesn't care about
perforations; it will use single, double, or unperfed, though the later
12x17 frame MGs and QT require single perf loaded with the perforations
toward the cassette bridge, or unperfed, to avoid perforations intruding
on image area).

However, a film sold for Double 8 (double perf, finer pitch perforation
than 16 mm single perf) typically comes in short camera rolls (25 feet,
which is shot, reloaded from the other end, and shot again, then split
after development and spliced to yield 50 feet of 8 mm film) compared to
the 16 mm that comes in 100 or 200 foot lengths.

But even J and C Photography can't seem to verify that
Fomapan R can be developed to a negative -- I asked them about it a
couple months ago, got an answer suggesting use of E-6 bleach, and when
I asked how to avoid bleaching the image as well as the AH layer, never
got a reply (they were waiting for information from Foma, and seemingly
never got it). The E-6 bleach would be perfect for reversal processing
-- but not much use if you want a negative.


I know that you're up to the experiment, just sacrifice a roll or two
and see if it suits you. Thiocyante should be easy to obtain.

When I have time, space, and money to experiment again, I'll probably do
just that; as you say, I can get thiocyanate from Photographer's
Formulary, and $8 (plus shipping, but I'd probably piggyback that with
an order for Classic 400 in 120, which I've been meaning to get anyway)
will get me enough film for a dozen rolls, should be plenty to
experiment on.

I'm smiling just thinking of the commotion at Foma hunting down the
one guy who can answer your questions.

Yeah, which is silly given that they have miles of the film around, and
a warehouse full of chemicals; they should be able to simply shoot a
short length and process it to verify.

You expect that of marketing me?



Robert Vervoordt, MFA

On Mon, 20 Sep 2004 11:23:02 GMT, Donald Qualls
wrote:

Robert Vervoordt wrote:

On Mon, 20 Sep 2004 00:40:48 GMT, Donald Qualls
wrote:

Surely, but with Fomapan R, the negative is impossible to see because of
the (not yet removed) silver AH layer. If I develop Fomapan R in, say,
HC-110 Dilution B, I'll get a solid black strip of film.


Oooh, nasty! That Is quite a bit different from all the other BW
reversal films I encountered or heard of.

Exactly. Fomapan R is a dedicated movie stock, completely unrelated to
Foma's still film emulsions, AFAIK. Silver AH is apparently common in
color movie stocks that will be bleached in processing, but Fomapan is
the only B&W stock I've heard of that has it.

In a reversal
process, the bleach step would remove that layer. I'm unclear on what
you're saying happens in the developer (or first dev, for reversal).


I got that wrong, alright. Still, if the AH layer is very fine
colloidal Silver, it might be capable of removal during development in
a normal negative developer with some small amount of Thiocyanate
added. Such layers are "usually" susceptable to quick dissolution by
Thiocyanate long before it would attack any Silver Halides or even
developed Silver grains. A quick test would reveal if that were so.

Yeah. "Might be."

As you say, a quick test would show this, though I'd be tempted to try
judicious overfixing first; I've acheived visible bleaching using rapid
fixer with additional acetic acid added (though it took a long soak),
and would expect to get results on a silver AH layer more quickly.

Boy. it had better be judicious, as raoid fixers are known to begin
bleaching silver very soon after the time is extended. This is
especially so with papers, but there have been some reports of it
affecting film as well. If it works quickly enough on the Silver AH
layer, that may be all you'll need. Still the addition of Thiocyanate
to the developer seems more elegant, as it cuts out that extra work
you described.

More on that question below.


; the
thiocyanate (or similar) sounds necessary to reversal processing of any
film (as a fog control for the final positive?),


No, as a method of clearing extremely fine Silver from the highlights.
This is only a consideration for reversal processing and the nead for
very clear highlights in projection. When it comes to negatives and
printing, the slight density in the highlights may be actually an
advantage as it would limit the range of negative densities slightly.

Okay, fine silver in the highlights (after reversal) *is* fog, is it
not?

Ah, the semantics! Without continuing with refining terms, possibly.
Let's just keep focussed on getting results that will serve your
needs.


No. it's not fog. it's much more severe. As experienced by you, with
Fomapan R it's a completely developed layer of colloidal Silver, and
not something an anti foggant would be likely to have any significant
effect upon.

Okay, like very severe fog, then -- somwhere, if I didn't toss it when
packing for my move, I have a roll of old Kodachrome II (expiry 1964)
that I found in a camera and developed in Diafine; it came out solid
black, but I was able to bleach in acidified rapid fixer (see above)
enough to verify that there were no salvageable images on the film. I
don't think that film had a silver AH layer, though.

It doesn't. It has a black backing on the base surface of the film
that has to be removed prior to development in an alkaline bath
folloed by a wsh, at least in machine processing. This is the same
black gunky stuff found in Eastmans motion picture stocks.

When using short ends of MP color film, I, and others, just wash it
off after stopping development. I takes a little scrubbing, but
doesn't affect the chemical processes. It is just some plasticky
stuff that can even be left on until after fixing without a penalty,
save making your reels look dirty. Get it off before washing, though
and don't let it dry on the film at all.

Now, since this is not a Silver AH, there is no need for any chemical
removal. It won't work. What happened with your Kodachrome may have
been that you were mislead by the RemJet backing that remained almost
intact on the prodessed film. Putting it in the rapid fixer then may
have been more than the weak imagees that were developed in the
emulsion could withstand, and they were bleaced out. How you got rid
of the rem jet is beyond me, unless the film was completely fogged and
the RemJet AH backing got removed by the Carbonate B bath; this does
happen in my experience, though I have almost always noticed some
residue that needed wiping. I have done this so often, that I am
primed to look for the slightest remnant.

There are too many wild cards in this instance to rely on it for
guidance.


Okay, I never saw that list before, but it was my understanding that
(for instance) Plus-X Reversal was pretty much the same as Plus-X Neg
and Plus-X Pan still photo emulsion, but movie films were expected to be
processed to much lower contrast, which lowers speed.

I think you snipped something here. I thought I pointed to Plus-X
reversal being the same as Panatomic-X negative.

Movie film processing leads to lower contrast and speed for the same
emulsion compared to its development in the usual still fim
developers. MP requirements are for tonalty, sharpness and graininess
in that order.


Yep. That's why the Tri-X emulsion, which is named Double-X Negative
in motion picture use, is rated at 200 or 250 in daylight. Ilford has
or had a Mark 5, which was the same as HP-5. I used both in still
camera work and found them to be the same as the still versions when
developed as suc.

I've seen pictures shot with Double-X Negative in 35 mm, they're much
grainier than Tri-X and were shot at EI 200 -- and no, this is not Super
XX from the 1950s, it was 35 mm movie stock bulk loaded into cassettes.
I don't think Double-X Negative is quite the same as Tri-X.

That wasn't my experience at all. I used Double-X that had a known
and proper storage history, so I know that heat, radiation and age
were not factors in my use. I developed both in the same developer,
same tank, same time and temp and together, at once. If some of these
factors were different, that might be the reason for the difference in
the results you saw.

and if I want/need EI 400 for a
subminiature camera, I'm stuck slitting 400TX or TMY (or similar Ilford
or Agfa products); none of the existing movie stocks will give EI above
200 in D-76.


Four-X reversal is actually the same as Tri-x or Double-X negative.
If developed as you would Tri-X Pan, it will have the same speed and
image chacteristics.

Unfortunately, Four-X Reversal isn't available in 16 mm, as far as I've
been able to tell; it might not be available at all any more. I can get
Double-X Negative, I think, which you're saying is the same stuff (but
if it's the same, why doesn't Kodak simply recommend different EI for
shooting as negative or positive instead of marketing as two different
films?).

Yeah, why? I think the marketing guys had a big say here. There are
probably some differences in the overcoat and some other conditioning
additives, but, aside from the lack of an anticurl layer on the base
of XX, I haven't noticed any real difference.


.
Or does the above equivalence of Tri-X Pan with Double-X

Negative movie film suggest that the Double-X Neg is subject to speed
reduction by the low contrast movie negative development, and just gets
back to Tri-X speed with the "boost" of reversal?

Different applications, different results. Development to a higher
contrast in somewhat different formulae could well account for all the
difference. It gets back to Tri-X speed in D-76 with still film
develoment times.



Not exactly, Double-X or Tri-X will get to the speed of Four-X
reversal with reversal processing. When processed as a still
negative, the extra processing time will boost speed and contrast over
the results obtained in the motion picture formulae's time and temp,
as well as its different formulation.

Okay, so Tri-X Pan still film is the same as Four-X Reversal? Then the
Tri-X (ISO 400) gets downrated to EI 200 for movie negative processing
due to lower contrast development, and uprated back to EI 400 for
reversal -- doesn't sound like I'm getting a speed boost with reversal,
just getting back what the movie process loses (unless I'd get another
stop with processing as a reversed still).

The speed gain of reversal processing seems to be more pronounced the
slower the basic emulsion. It begins to taper off as the film's
basic, negative speed is increased.

Pan-X 1 2/3 stops
Plus-X 1 1/3 stops
XX 1 stop.

Don't forget, all the reversal processes, up to recently have had the
same first development applied to all the emulsions we are considering
here. And the results show great contrast boosts for the slower films.
The speed boost are reflective of that.

In still practice, we generally use shorter times in order to keep
pictorial results consistent. This would eliminate greater speed
differentials for the slow films.

This is all very confusing, and none of it would be necessary if I could
just buy ISO 400 B&W negative film in 16 mm (preferably Tri-X Pan, aka
400TX, which gives a very usable EI 1600 without much if any grain
increase when developed in Diafine).


Get some 16mm Double-X and treat it the same as your still fim, tri-X,
and all will be as you desire.

Okay, I might have to see if I can't land a roll of that stuff. It was,
IIRC, around $25 for 200 feet, which is quite attractive (other than the
daunting prospect of having 99 rolls left over if I don't like it).
Won't be money for experimentation for a while, though; this move just
keeps sucking up more and more money...

Oh, I hear you! I still haven't got a place to move to.

Hey, just spool of one roll at a time. If you don't like it, sell the
remaider as a short end for movie use/

Okay, clarify this for me -- if something dissolves metallic silver, to
me, that's a bleach; it'll dissolve image silver and latent image specks
just as readily as it will remove a silver AH layer. As a result, it
seems it ought to eat up shadows in a negative and reduce speed, both by
killing the weakest/sparsest latent image specks before they can be
developed, and by dissolving away the least dense areas of the image
just as it dissolves the AH silver.

The shadow densities are usually made up of the largest, most
resistant grains in the image; usually Iosdides. Highlights will
have a greater proportion of small, slower grains. That's why
Thiocyanate clears highlights and doesn't affect the rest of the image
in the time normally encountered in first development. Let it sit for
an hour or more and see what happens, though.


The AH Silver is of a different form than the Silver that forms the
image. It is already reduced, and blackened. That is how it works as
an AH layer during exposure. The Thiocyante can attack it
immediately, as it is much more finely formed than any Halide or
Silver grain that will form the image. If this were not the case, it
wouldn't work the way it does in a reversal process.

Developed image silver is reduced, as is the metallic silver that forms
a latent image speck -- and I'd argue that a latent image speck, a tiny
fraction of a halide grain, is smaller than the particles of colloidal
silver in the AH layer.

Colloidal silver is smallest.

In a reversal process, the bleach step that
removes the silver image (either from the first dev, or from both dev
steps, depending on whether you're using a silver-based B&W or a dye
based color film) also removes the AH layer.

Sure, if it hasn't been removed from the emulsion before, by a solvent
action, such as Thiocyanate. So, according to what you said, why
doesn;t this work with Fomapan? Was the film light stuck?

From my reading on reversing conventional B&W still films, thiocyanate,
thiosulfate, etc. in the first dev is to remove "stubborn" halide
(undevelopable even after maximum exposure) from the most exposed areas
to prevent fogged highlights after reversal exposure and redevelopment.

OK, then which Halides would be left? The smallest, which probably
never reached a threshold of exposure to make them developable.

This is not at all the same as bleaching away the metallic silver of
the AH layer.

I wouldn't say "not at all", as what is happening in both cases is
that the Thiocyanate is able to dissolve the smallest particles much
sooner than it can begin to have an effect on anything larger. It
also works on Colloidal particles and Chlorides before it can affect
the Bromides and Iododes which make up the majority of the rest of
the distribution. The Chlorides ar the Halides with the least
sensitivity to light.

A "silver solvent", at least as the term is usually used
relative to development, is a halide solvent, not a metallic silver
solvent;

That's to general and misses the differences in actions on the
different Halides and forms of Silver metal in the emulsion. See
above.

sulfite, thiosulfate, etc. are silver solvents, and their
intended function (at least in that regard, since sulfite does so many
other things) is generally reduction of grain by reducing halide grain
size and preventing excessive growth of silver grains.

Add fixing for Thiosulfate. That affects Halides long before it
affects Silver.

Thiocyanate,
IIRC, is a true bleach similar to ferricyanides, dichromates,
permanganates, etc.; that is, it is capable of reacting with and
dissolving or rehalogentating reduced silver.

No, it's more like Thiosulfate, in that it can "fix" film. It doesn't
blaech well, as it barfs on larger Halide grains and those with
Iodide.


Silver is silver -- chemically, if you dissolve silver metal one place,
you'll dissolve it anywhere else in the same bath, and dissolving silver
*has to* cost you shadow speed in the negative.

No, se info Iodides.


No, it would do that in a reversal developer, as well, if that were
so. You can safely assume that since it works in a reversal first
developer, it can work in a negative developer in the same fashio.
While there are differences in the energy of reversal and negative
developers, they are not enough to make much difference. I did it and
it worked with something I used.

What film have you developed with a thiocyanate-added B&W developer that
had a silver AH layer? What developer did you use, and how much
thiocyanate did you add? Knowing this could save me many hours of
experimentation...

Hmm, maybe I didn't. I can't recall any BW reversal or negative film
with aSilver AH layer. I must have been thinking of using Fujicolor
neg MP film in my speed boosting process that used first development
in a BW formula and rehalogenation to finish in the colr development
remaider of the process.

Single perf won't work?

Single perf works fine (the Minolta 16 advance system doesn't care about
perforations; it will use single, double, or unperfed, though the later
12x17 frame MGs and QT require single perf loaded with the perforations
toward the cassette bridge, or unperfed, to avoid perforations intruding
on image area).

However, a film sold for Double 8 (double perf, finer pitch perforation
than 16 mm single perf) typically comes in short camera rolls (25 feet,
which is shot, reloaded from the other end, and shot again, then split
after development and spliced to yield 50 feet of 8 mm film) compared to
the 16 mm that comes in 100 or 200 foot lengths.

But even J and C Photography can't seem to verify that
Fomapan R can be developed to a negative -- I asked them about it a
couple months ago, got an answer suggesting use of E-6 bleach, and when
I asked how to avoid bleaching the image as well as the AH layer, never
got a reply (they were waiting for information from Foma, and seemingly
never got it). The E-6 bleach would be perfect for reversal processing
-- but not much use if you want a negative.


I know that you're up to the experiment, just sacrifice a roll or two
and see if it suits you. Thiocyante should be easy to obtain.

When I have time, space, and money to experiment again, I'll probably do
just that; as you say, I can get thiocyanate from Photographer's
Formulary, and $8 (plus shipping, but I'd probably piggyback that with
an order for Classic 400 in 120, which I've been meaning to get anyway)
will get me enough film for a dozen rolls, should be plenty to
experiment on.

I'm smiling just thinking of the commotion at Foma hunting down the
one guy who can answer your questions.

Yeah, which is silly given that they have miles of the film around, and
a warehouse full of chemicals; they should be able to simply shoot a
short length and process it to verify.

You expect that of marketing me?



Robert Vervoordt, MFA

Robert Vervoordt wrote:

It doesn't. It has a black backing on the base surface of the film
that has to be removed prior to development in an alkaline bath
folloed by a wsh, at least in machine processing. This is the same
black gunky stuff found in Eastmans motion picture stocks.


Is there any other still camera film that has the remjet AH layer of Kodachrome?

Robert Vervoordt wrote:

It doesn't. It has a black backing on the base surface of the film
that has to be removed prior to development in an alkaline bath
folloed by a wsh, at least in machine processing. This is the same
black gunky stuff found in Eastmans motion picture stocks.


Is there any other still camera film that has the remjet AH layer of Kodachrome?

On Tue, 21 Sep 2004 00:16:29 GMT, wrote:

Robert Vervoordt wrote:

It doesn't. It has a black backing on the base surface of the film
that has to be removed prior to development in an alkaline bath
folloed by a wsh, at least in machine processing. This is the same
black gunky stuff found in Eastmans motion picture stocks.


Is there any other still camera film that has the remjet AH layer of Kodachrome?

I don't think there are. None come to mind.


Robert Vervoordt, MFA

On Tue, 21 Sep 2004 00:16:29 GMT, wrote:

Robert Vervoordt wrote:

It doesn't. It has a black backing on the base surface of the film
that has to be removed prior to development in an alkaline bath
folloed by a wsh, at least in machine processing. This is the same
black gunky stuff found in Eastmans motion picture stocks.


Is there any other still camera film that has the remjet AH layer of Kodachrome?

I don't think there are. None come to mind.


Robert Vervoordt, MFA

On Mon, 20 Sep 2004 14:42:37 -0400, Robert Vervoordt
wrote:


:

On Mon, 20 Sep 2004 00:40:48 GMT, Donald Qualls
wrote:

Robert Vervoordt wrote

What film have you developed with a thiocyanate-added B&W developer that
had a silver AH layer? What developer did you use, and how much
thiocyanate did you add? Knowing this could save me many hours of
experimentation...

Hmm, maybe I didn't. I can't recall any BW reversal or negative film
with aSilver AH layer. I must have been thinking of using Fujicolor
neg MP film in my speed boosting process that used first development
in a BW formula and rehalogenation to finish in the colr development
remaider of the process.


You know, this brought back memories and some details. Got me
thinking about it some more. When the Fujicolor negative came out of
the first deveoper it showed the image and the base was a cloudy
Orange color. I can't remember any Black obscuring the view through
the base to the image. I know Fuji was using an internal AH layer
right under the Red sensitive layer. Either this AH layer was not
Silver or it was and the layer got dissolved in the developer. For a
speed boost I was using Crawley's FX-11. This had a lot of solvent
action, from the 125 grams of Sulfite and the inclusion of Glycin,
which gets a boosted solvent action from more than a small amount of
Sulfite.]

That brought me back to something I alluded to in a previous post, in
passing. Are you sure your Fomapan R has not beeen light struck or
fogged?

Try these

1. Develop an unexposed strip in D-76 in total darkness.

2. Develop in bright light.

3. Note any differences? If they are identical, it indicates
either a light stuck, exposed film or severe fog.

4. Fix the film without development.

5. If it is Black, it means the AH of Fomapan R is different from
others, as you described. If not then, not.

We may be on a wild goose chase here.



















I'm smiling just thinking of the commotion at Foma hunting down the
one guy who can answer your questions.

Yeah, which is silly given that they have miles of the film around, and
a warehouse full of chemicals; they should be able to simply shoot a
short length and process it to verify.

You expect that of marketing me?

I meant "men".

But you knew that.


Robert Vervoordt, MFA

On Mon, 20 Sep 2004 14:42:37 -0400, Robert Vervoordt
wrote:


:

On Mon, 20 Sep 2004 00:40:48 GMT, Donald Qualls
wrote:

Robert Vervoordt wrote

What film have you developed with a thiocyanate-added B&W developer that
had a silver AH layer? What developer did you use, and how much
thiocyanate did you add? Knowing this could save me many hours of
experimentation...

Hmm, maybe I didn't. I can't recall any BW reversal or negative film
with aSilver AH layer. I must have been thinking of using Fujicolor
neg MP film in my speed boosting process that used first development
in a BW formula and rehalogenation to finish in the colr development
remaider of the process.


You know, this brought back memories and some details. Got me
thinking about it some more. When the Fujicolor negative came out of
the first deveoper it showed the image and the base was a cloudy
Orange color. I can't remember any Black obscuring the view through
the base to the image. I know Fuji was using an internal AH layer
right under the Red sensitive layer. Either this AH layer was not
Silver or it was and the layer got dissolved in the developer. For a
speed boost I was using Crawley's FX-11. This had a lot of solvent
action, from the 125 grams of Sulfite and the inclusion of Glycin,
which gets a boosted solvent action from more than a small amount of
Sulfite.]

That brought me back to something I alluded to in a previous post, in
passing. Are you sure your Fomapan R has not beeen light struck or
fogged?

Try these

1. Develop an unexposed strip in D-76 in total darkness.

2. Develop in bright light.

3. Note any differences? If they are identical, it indicates
either a light stuck, exposed film or severe fog.

4. Fix the film without development.

5. If it is Black, it means the AH of Fomapan R is different from
others, as you described. If not then, not.

We may be on a wild goose chase here.



















I'm smiling just thinking of the commotion at Foma hunting down the
one guy who can answer your questions.

Yeah, which is silly given that they have miles of the film around, and
a warehouse full of chemicals; they should be able to simply shoot a
short length and process it to verify.

You expect that of marketing me?

I meant "men".

But you knew that.


Robert Vervoordt, MFA