pyro

I read somewhere about a guy that justified moving from large format to
medium format due to pyro.
What the heck is pyro and what does it do?
Is it dangerous/toxic? it sounds both!

Thanks,
Matt A.

"Matt Ashbrook" wrote in message
news:jUGkc.6570$I%1.583567@attbi_s51...
I read somewhere about a guy that justified moving from large format to
medium format due to pyro.
What the heck is pyro and what does it do?
Is it dangerous/toxic? it sounds both!

Thanks,
Matt A.



Matt,

Pyro, or Pyrogallol, or Pyrogallic Acid is one of the oldest developing
agents. It is a tanning developer and staining developer.

A tanning developer is one that 'tans' (like leather is tanned) the emulsion
and leaves it hardened and therefore less susceptible to damage.

A staining developer leave a proportional or general stain over the entire
negative.

The tanning part is easy to understand the benefits. The stain is hard to
understand. Pyro developers (as well as other staining developers) have
seen a resurgence of interest as this stain works so well with VC paper.
Pyro works (IMHO) better than the other staining developers.

Another benefit to the stain is it provides (in the case of Pyro) a stain
proportional to the silver. This stain also has a masking effect of the
grain structure and appears to the eye to have reduced grain (although grain
is not reduced). The developer also enhances edge effects and increase
apparent sharpness of the image. Pyro also increases the tonality of the
negative and decreases contrast (the mask provides this contrast reduction
by filtering blue light). All these benefits add up to an image that is
easier to print, especially on VC paper.

Pyro is a toxin. However, it's not as toxic as say Rat Poison or Drano.
Pyro gets a bad reputation as it is easily absorbed through the skin. For
those LF users who tray process, they may end up with Liver or Kidney damage
if they don't take rational precautions like gloves when the stick their
hand in the solution. Taking those rational precautions with Pyro (and all
chemicals) is prudent. Pyro is used in Hair Dye, Leather Tanning and some
cosmetics. So you may already be exposed to Pyro if you wear a leather belt
or shoes.

If I owned LF equipment, I would not take the step back to MF just because
of Pyro! You can never achieve the micro contrast or the tonality of a LF
negative with a MF negative. Same applies to MF and 35mm.

Pyro does not work with all films the same way and you will need to
experiment and maybe even give up old standby films to get better images.

Do I think the disadvantages outweigh the advantages? No! I'm not sure
Pyro is any more toxic than other chemicals I have in the Darkroom or even
under the kitchen sink. Heck, some paint thinners are more toxic if taken
internally. I just don't plan on drinking either of them;~)

Hope this had been helpful.

Jim



__________________________________________________ _____________________________
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Doesn't sound worth the trouble for my use. Idon't particularly like toned
prints, anyway.
This guy who back stepped to medium from large format did so (he says, not
me)partly because of the cost of equipment.
I just am getting started in large format and if I dump anything because of
cost, it will be the Hasselblad system! Now that's expensive! heck my 4 x 5
system is going to be into my wallet for the grand total of about $500 give
or take and that includes just having the bellows completely rebuilt.
No pyro for me, thanks.

Thanks,
Matt A.
"Jim Phelps" wrote in message
...

"Matt Ashbrook" wrote in message
news:jUGkc.6570$I%1.583567@attbi_s51...
I read somewhere about a guy that justified moving from large format to
medium format due to pyro.
What the heck is pyro and what does it do?
Is it dangerous/toxic? it sounds both!

Thanks,
Matt A.



Matt,

Pyro, or Pyrogallol, or Pyrogallic Acid is one of the oldest developing
agents. It is a tanning developer and staining developer.

A tanning developer is one that 'tans' (like leather is tanned) the
emulsion
and leaves it hardened and therefore less susceptible to damage.

A staining developer leave a proportional or general stain over the entire
negative.

The tanning part is easy to understand the benefits. The stain is hard to
understand. Pyro developers (as well as other staining developers) have
seen a resurgence of interest as this stain works so well with VC paper.
Pyro works (IMHO) better than the other staining developers.

Another benefit to the stain is it provides (in the case of Pyro) a stain
proportional to the silver. This stain also has a masking effect of the
grain structure and appears to the eye to have reduced grain (although
grain
is not reduced). The developer also enhances edge effects and increase
apparent sharpness of the image. Pyro also increases the tonality of the
negative and decreases contrast (the mask provides this contrast reduction
by filtering blue light). All these benefits add up to an image that is
easier to print, especially on VC paper.

Pyro is a toxin. However, it's not as toxic as say Rat Poison or Drano.
Pyro gets a bad reputation as it is easily absorbed through the skin. For
those LF users who tray process, they may end up with Liver or Kidney
damage
if they don't take rational precautions like gloves when the stick their
hand in the solution. Taking those rational precautions with Pyro (and
all
chemicals) is prudent. Pyro is used in Hair Dye, Leather Tanning and some
cosmetics. So you may already be exposed to Pyro if you wear a leather
belt
or shoes.

If I owned LF equipment, I would not take the step back to MF just because
of Pyro! You can never achieve the micro contrast or the tonality of a LF
negative with a MF negative. Same applies to MF and 35mm.

Pyro does not work with all films the same way and you will need to
experiment and maybe even give up old standby films to get better images.

Do I think the disadvantages outweigh the advantages? No! I'm not sure
Pyro is any more toxic than other chemicals I have in the Darkroom or even
under the kitchen sink. Heck, some paint thinners are more toxic if taken
internally. I just don't plan on drinking either of them;~)

Hope this had been helpful.

Jim




__________________________________________________ __________________________
___
Posted Via Uncensored-News.Com - Accounts Starting At $6.95 -
http://www.uncensored-news.com
The Worlds Uncensored News Source

Pyro does not tone the print. It tones the negative.

When you do not use a hardening fixer and stain the negative by reinserting
the negative in the developer you used in the developing the negative, it
turns the highlight areas a slight tan rather than grey. This tan color
when printed with a VC paper reduces the contrast between these higher Zones
to a lower Zone. This is a help when trying to reduce the range between
middle Zone VI and the highlights, which could be as be as high as Zone XII.

I do not know about sharpness, but it definitely will make high contrast
image easier to print.



"Matt Ashbrook" wrote in message
news:nSMkc.7540$Ik.645605@attbi_s53...
| Doesn't sound worth the trouble for my use. Idon't particularly like toned
| prints, anyway.
| This guy who back stepped to medium from large format did so (he says, not
| me)partly because of the cost of equipment.
| I just am getting started in large format and if I dump anything because
of
| cost, it will be the Hasselblad system! Now that's expensive! heck my 4 x
5
| system is going to be into my wallet for the grand total of about $500
give
| or take and that includes just having the bellows completely rebuilt.
| No pyro for me, thanks.
|
| Thanks,
| Matt A.
| "Jim Phelps" wrote in message
| ...
|
| "Matt Ashbrook" wrote in message
| news:jUGkc.6570$I%1.583567@attbi_s51...
| I read somewhere about a guy that justified moving from large format
to
| medium format due to pyro.
| What the heck is pyro and what does it do?
| Is it dangerous/toxic? it sounds both!
|
| Thanks,
| Matt A.
|
|
|
| Matt,
|
| Pyro, or Pyrogallol, or Pyrogallic Acid is one of the oldest
developing
| agents. It is a tanning developer and staining developer.
|
| A tanning developer is one that 'tans' (like leather is tanned) the
| emulsion
| and leaves it hardened and therefore less susceptible to damage.
|
| A staining developer leave a proportional or general stain over the
entire
| negative.
|
| The tanning part is easy to understand the benefits. The stain is hard
to
| understand. Pyro developers (as well as other staining developers) have
| seen a resurgence of interest as this stain works so well with VC paper.
| Pyro works (IMHO) better than the other staining developers.
|
| Another benefit to the stain is it provides (in the case of Pyro) a
stain
| proportional to the silver. This stain also has a masking effect of the
| grain structure and appears to the eye to have reduced grain (although
| grain
| is not reduced). The developer also enhances edge effects and increase
| apparent sharpness of the image. Pyro also increases the tonality of
the
| negative and decreases contrast (the mask provides this contrast
reduction
| by filtering blue light). All these benefits add up to an image that is
| easier to print, especially on VC paper.
|
| Pyro is a toxin. However, it's not as toxic as say Rat Poison or Drano.
| Pyro gets a bad reputation as it is easily absorbed through the skin.
For
| those LF users who tray process, they may end up with Liver or Kidney
| damage
| if they don't take rational precautions like gloves when the stick their
| hand in the solution. Taking those rational precautions with Pyro (and
| all
| chemicals) is prudent. Pyro is used in Hair Dye, Leather Tanning and
some
| cosmetics. So you may already be exposed to Pyro if you wear a leather
| belt
| or shoes.
|
| If I owned LF equipment, I would not take the step back to MF just
because
| of Pyro! You can never achieve the micro contrast or the tonality of a
LF
| negative with a MF negative. Same applies to MF and 35mm.
|
| Pyro does not work with all films the same way and you will need to
| experiment and maybe even give up old standby films to get better
images.
|
| Do I think the disadvantages outweigh the advantages? No! I'm not sure
| Pyro is any more toxic than other chemicals I have in the Darkroom or
even
| under the kitchen sink. Heck, some paint thinners are more toxic if
taken
| internally. I just don't plan on drinking either of them;~)
|
| Hope this had been helpful.
|
| Jim
|
|
|
|
|
__________________________________________________ __________________________
| ___
| Posted Via Uncensored-News.Com - Accounts Starting At $6.95 -
| http://www.uncensored-news.com
| The Worlds Uncensored News Source
|
|
|
|

"Matt Ashbrook" wrote in message
news:nSMkc.7540$Ik.645605@attbi_s53...
Doesn't sound worth the trouble for my use. Idon't particularly like toned
prints, anyway.
This guy who back stepped to medium from large format did so (he says, not
me)partly because of the cost of equipment.
I just am getting started in large format and if I dump anything because
of
cost, it will be the Hasselblad system! Now that's expensive! heck my 4 x
5
system is going to be into my wallet for the grand total of about $500
give
or take and that includes just having the bellows completely rebuilt.
No pyro for me, thanks.

Thanks,
Matt A.

Matt,

Just to be sure you understand. It does not effect the color of the
print. It tones the negative.

You really shouldn't give up until you actually give it a try.

Jim

Anyone who can offer actual experience of this developer when used with
EFKE 25 and 50 ASA?

In article ,
"Neil Purling" wrote:

Anyone who can offer actual experience of this developer when used with
EFKE 25 and 50 ASA?

Yes.
--
LF website http://members.bellatlantic.net/~gblank

For best results expand this window at least 6" at 1152 x 768 resolution

Good.
I was interested in trying the developer as I have had problems with the
contrast of EFKE25ASA in certain lighting situations.
I am currently using some PL25 sheet film and the KB25 35mm.
I would like to know how easy it was to print the resulting negatives
compared to using a normal developer like Rodinal.
I have used this in the past but the contrast means scenes shot in sunlight
need a extremely soft filter to print.
I have amended my developement times and now rate the film at 25ASA in
daylight, not the 40 or 50 ASA in the literature ive seen.
It remains to be seen how my latest results print like as they were exposed
in bright sunlight too.
Any problems and I would like to try pyro and see if the highlights print
softer.

At least with 4x5 its easy to establish film speed as I make a test strip as
with a print when I progressively withdraw the dark slide and make multiple
exposures.
Obviously the kit I buy may be a different formulation and so I have to
establish a dev time for myself.

My testing indicates for my practice it is a true 25asa film.
With D23, PMK & HC110 that is for the PL25.
I wrote an article about the film for View camera
magazine on the film last year. If you wish I'll dig up the
issue number so you can research it further.



In article ,
"Neil Purling" wrote:

Good.
I was interested in trying the developer as I have had problems with the
contrast of EFKE25ASA in certain lighting situations.
I am currently using some PL25 sheet film and the KB25 35mm.
I would like to know how easy it was to print the resulting negatives
compared to using a normal developer like Rodinal.
I have used this in the past but the contrast means scenes shot in sunlight
need a extremely soft filter to print.
I have amended my developement times and now rate the film at 25ASA in
daylight, not the 40 or 50 ASA in the literature ive seen.
It remains to be seen how my latest results print like as they were exposed
in bright sunlight too.
Any problems and I would like to try pyro and see if the highlights print
softer.

At least with 4x5 its easy to establish film speed as I make a test strip as
with a print when I progressively withdraw the dark slide and make multiple
exposures.
Obviously the kit I buy may be a different formulation and so I have to
establish a dev time for myself.


--
LF website http://members.bellatlantic.net/~gblank

For best results expand this window at least 6" at 1152 x 768 resolution

I was going to try the Pyro kit made by Retro Photographic in the UK as they
also retail the Classic Pan and EFKE emulsions.
Which of these respond particularly well in pyro developer?
Are there any of the Ilford emulsions which work well?