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[email protected] February 10th 11 01:26 AM

Lens Cell Cleaning
 
On 2/9/2011 10:41 AM, Cheesehead wrote:

And the rear has a ring holding it in place, which should be removable
easily with a spanner wrench.


I'm not sure what you are saying here but do NOT remove the glass itself
from it's mount but unscrew the whole cell from the shutter to clean the
front/inner surface and you can also clean the rear of the front element
while you are there by opening the shutter.

Stephey

Richard Knoppow February 10th 11 04:41 AM

Lens Cell Cleaning
 

wrote in message
...
On 2/9/2011 10:41 AM, Cheesehead wrote:

And the rear has a ring holding it in place, which should
be removable
easily with a spanner wrench.


I'm not sure what you are saying here but do NOT remove
the glass itself from it's mount but unscrew the whole
cell from the shutter to clean the front/inner surface and
you can also clean the rear of the front element while you
are there by opening the shutter.

Stephey


If its a standard Triplet the back cell will be a single
lens so there is no need to remove the glass. The front cell
will have two elements. Usually in larger lenses there is a
threaded back cap on the cell but it may have a retaining
ring on the front which is more common for smaller lenses.
If a back cap its easy to remove. The elements are clamped
between concentric edges in the cell so are automatically
centered.
If the cap is too tight for removal with simple finger
grip use one of those rubber jar grippers. It won't mar the
surface. If you grip too tightly it will clamp it and make
it even harder to remove.
I agree with the others about cleaning but if the lens
is oily the standard optical cleaner is pure acetone
followed by dry isopropyl alcohol. Window cleaner like
Windex may streak the lens if not followed by alcohol. The
newer butyl alcohol "streak-free" cleaners are better.
While ammonia is alkaline and strong alkalies can
dissolve some kinds of glass there is no real danger from
the very dilte ammonia in Windex and similar cleaners.
If you use acetone be careful of the edge paint, if any,
and of the paint on the cell because it will dissolve both.
I do not recommend cleaning inside elements when in a
shutter because there is too much danger of getting the
cleaning fluid into the shutter, take the cell out.


--
--
Richard Knoppow
Los Angeles, CA, USA




David Nebenzahl February 10th 11 09:53 PM

Lens Cell Cleaning
 
On 2/10/2011 12:47 PM Cheesehead spake thus:

I'm not absolutely certain about the Geronar formula. It is reported
to be a Tessar.
That said, the rear should be a single piece of glass. But it is not.
If it is a cemented piece, then it is not a true Tessar and the
fogging may be in the cement.
That would be bad.
I've not found the formula out there to describe the lens.
In the mean time I've been searching for a replacement rear cell.


It's not clear you've tried to remove and clean the rear cell; have you?
If not, you should. What've you got to lose? If in fact the cement is
clouded (which I think is probably unlikely), you've got to replace the
thing anyhow (or have it recemented), so why not just pull it out and
clean it? It ain't rocket surgery, you know.


--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.

[email protected] February 11th 11 02:20 AM

Lens Cell Cleaning
 
On 2/10/2011 3:47 PM, Cheesehead wrote:


I'm not absolutely certain about the Geronar formula. It is reported
to be a Tessar.


Not sure who told you that but it's not a tessar, it's a triplet. A
modern version of the classic cooke triplet. And a rather good one I
might add.

Stephey


[email protected] February 11th 11 03:01 AM

Lens Cell Cleaning
 
On 2/10/2011 7:54 PM, Cheesehead wrote:

I have, of course, unscrewed the cell from the shutter and observed
that the fogging is inside the rear cell.


Hmm that's odd. It should be a single element so hard to imagine there
being fogging inside it?

Stephey


David Nebenzahl February 11th 11 03:14 AM

Lens Cell Cleaning
 
On 2/10/2011 4:54 PM Cheesehead spake thus:

On Feb 10, 4:53 pm, David Nebenzahl wrote:

It's not clear you've tried to remove and clean the rear cell; have
you? If not, you should. What've you got to lose? If in fact the
cement is clouded (which I think is probably unlikely), you've got
to replace the thing anyhow (or have it recemented), so why not
just pull it out and clean it? It ain't rocket surgery, you know.


I have, of course, unscrewed the cell from the shutter and observed
that the fogging is inside the rear cell.


Well, did you try to clean the outer surfaces? Sorry, not clear from
your postings.


--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.

[email protected] February 11th 11 03:50 AM

Lens Cell Cleaning
 
On 2/10/2011 10:14 PM, David Nebenzahl wrote:
On 2/10/2011 4:54 PM Cheesehead spake thus:

On Feb 10, 4:53 pm, David Nebenzahl wrote:

It's not clear you've tried to remove and clean the rear cell; have
you? If not, you should. What've you got to lose? If in fact the
cement is clouded (which I think is probably unlikely), you've got
to replace the thing anyhow (or have it recemented), so why not
just pull it out and clean it? It ain't rocket surgery, you know.


I have, of course, unscrewed the cell from the shutter and observed
that the fogging is inside the rear cell.


Well, did you try to clean the outer surfaces? Sorry, not clear from
your postings.



I'm confused on his post as well. It's a triplet and as such the rear
"cell" would be a single element. I suppose the glass itself -could- be
bad and have fogging inside the single element itself? Or the coating is
screwed up?

Stephey

David Nebenzahl February 11th 11 04:03 AM

Lens Cell Cleaning
 
On 2/10/2011 7:50 PM spake thus:

On 2/10/2011 10:14 PM, David Nebenzahl wrote:

On 2/10/2011 4:54 PM Cheesehead spake thus:

On Feb 10, 4:53 pm, David Nebenzahl
wrote:

It's not clear you've tried to remove and clean the rear cell;
have you? If not, you should. What've you got to lose? If in
fact the cement is clouded (which I think is probably
unlikely), you've got to replace the thing anyhow (or have it
recemented), so why not just pull it out and clean it? It ain't
rocket surgery, you know.

I have, of course, unscrewed the cell from the shutter and
observed that the fogging is inside the rear cell.


Well, did you try to clean the outer surfaces? Sorry, not clear
from your postings.


I'm confused on his post as well. It's a triplet and as such the rear
"cell" would be a single element. I suppose the glass itself -could- be
bad and have fogging inside the single element itself?


No, it could not. Glass itself doesn't fog, at least not under most
conventional terrestrial* conditions.

Or the coating is screwed up?


Is that lens even coated? Even if so, coatings don't generally fog.
Either the lens surfaces themselves are schmutzified (that's the
technical term), or it's a cemented element and the cement has gone bad.

If the latter, the elements can be separated and recemented. This
process has actually been described here by R. Knoppow. People like S.
Grimes can also perform this particular kind of alchemy.


* Sorry, been reading about black holes and other weird cosmological
phenomena, where anything can happen.


--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.

[email protected] February 11th 11 06:03 PM

Lens Cell Cleaning
 
On 2/11/2011 8:27 AM, Cheesehead wrote:


that also has me puzzled. It is described as a Tessar, but I am only
going by what I can find.


Where did you see that? EVERY source I found, except people saying they
are guessing at the formula, like you are here, say it's a triplet.

http://www.apug.org/forums/forum44/1...8-geronar.html

http://www.hevanet.com/cperez/test/BigMash210.html

http://www.bhphotovideo.com/c/produc...nar_Copal.html

http://greenspun.com/bboard/q-and-a-...?msg_id=002Owe

http://en.wikipedia.org/wiki/Rodenstock_GmbH#Geronar

http://photo.net/large-format-photography-forum/003EZO

The rear cell *looks like* it has two elements in it.


Not sure how that is possible.

Stephey


Richard Knoppow February 11th 11 07:20 PM

Lens Cell Cleaning
 

"Cheesehead" wrote in message
...
On Feb 9, 11:41 pm, "Richard Knoppow"
wrote:

If its a standard Triplet the back cell will be a single
lens so there is no need to remove the glass. The front
cell
will have two elements. Usually in larger lenses there is
a
threaded back cap on the cell but it may have a retaining
ring on the front which is more common for smaller lenses.
If a back cap its easy to remove. The elements are clamped
between concentric edges in the cell so are automatically
centered.
If the cap is too tight for removal with simple finger
grip use one of those rubber jar grippers. It won't mar
the
surface. If you grip too tightly it will clamp it and make
it even harder to remove.
I agree with the others about cleaning but if the lens
is oily the standard optical cleaner is pure acetone
followed by dry isopropyl alcohol. Window cleaner like
Windex may streak the lens if not followed by alcohol. The
newer butyl alcohol "streak-free" cleaners are better.
While ammonia is alkaline and strong alkalies can
dissolve some kinds of glass there is no real danger from
the very dilte ammonia in Windex and similar cleaners.
If you use acetone be careful of the edge paint, if any,
and of the paint on the cell because it will dissolve
both.
I do not recommend cleaning inside elements when in a
shutter because there is too much danger of getting the
cleaning fluid into the shutter, take the cell out.

--
--
Richard Knoppow
Los Angeles, CA, USA


I'm not absolutely certain about the Geronar formula. It is
reported
to be a Tessar.
That said, the rear should be a single piece of glass. But
it is not.
If it is a cemented piece, then it is not a true Tessar and
the
fogging may be in the cement.
That would be bad.
I've not found the formula out there to describe the lens.
In the mean time I've been searching for a replacement rear
cell.

I think you mis-typed, a Tessar _does_ have a cemented
rear component, a Triplet does not. I also don't remember
what a Geronar is but think it may be a Dialyte. Have to
look it up. If it is a Dialyte its a four element air spaced
lens. Both front and rear cells will have two lenses with an
air space between. There should be a back cap on both cells
allowing access to the inner surfaces.
If its actually a Tessary type and there is haze inside
the rear component its due to the cement being damaged. Most
old lenses were cemented with Canada Balsam. This has good
optical properties but is subject to damage from low
temperatures, which will make it milky. It also tends to dry
out at the edges unless very well sealed, so that its common
for CB cemented lenses to show a yellow ring of oxidation at
the edge. If this goes on long enough the cement at the
edges may crystalize. While a small amount of oxidation at
the edge (its not true separation) does little harm it can
cause problems if it progresses far enough. Most of these
lenses can be recemented. Modern cements are synthetic,
either binary cements similar to common epoxy or UV curing
cements. Some lenses built in about the 1950s have an
earlier synthetic cement of a type cured by heat. Some of
these show degradation or true separation due to problems in
the cementing process. I've seen a number of Kodak lenses
that seemed slightly hazy but on close examination with a
magnifier and correct light, it was evident that the cement
layer had become reticulated, having a sort of orange-peel
look. Some Zeiss lenses and some Wollendak lenses from this
period have actual large bubbles in the cement where it has
completely separated from the glass. All these can be
recemented if they are thought valuable enough. One can try
it at home using a makeshift method of centering but any
valuable lens should be submitted to someone like John van
Stelten who has the proper equipment to do it the right way.


--
--
Richard Knoppow
Los Angeles, CA, USA



--
--
Richard Knoppow
Los Angeles, CA, USA





Jean-David Beyer February 12th 11 05:33 PM

Lens Cell Cleaning
 
Cheesehead wrote:
Cheesehead wrote:
On Feb 9, 11:41 pm, "Richard Knoppow" wrote:

If its a standard Triplet the back cell will be a single
lens so there is no need to remove the glass. The front cell
will have two elements. Usually in larger lenses there is a
threaded back cap on the cell but it may have a retaining
ring on the front which is more common for smaller lenses.
If a back cap its easy to remove. The elements are clamped
between concentric edges in the cell so are automatically
centered.
If the cap is too tight for removal with simple finger
grip use one of those rubber jar grippers. It won't mar the
surface. If you grip too tightly it will clamp it and make
it even harder to remove.
I agree with the others about cleaning but if the lens
is oily the standard optical cleaner is pure acetone
followed by dry isopropyl alcohol. Window cleaner like
Windex may streak the lens if not followed by alcohol. The
newer butyl alcohol "streak-free" cleaners are better.
While ammonia is alkaline and strong alkalies can
dissolve some kinds of glass there is no real danger from
the very dilte ammonia in Windex and similar cleaners.
If you use acetone be careful of the edge paint, if any,
and of the paint on the cell because it will dissolve both.
I do not recommend cleaning inside elements when in a
shutter because there is too much danger of getting the
cleaning fluid into the shutter, take the cell out.

--
--
Richard Knoppow
Los Angeles, CA, USA


I'm not absolutely certain about the Geronar formula. It is reported
to be a Tessar.
That said, the rear should be a single piece of glass. But it is not.
If it is a cemented piece, then it is not a true Tessar and the
fogging may be in the cement.
That would be bad.
I've not found the formula out there to describe the lens.
In the mean time I've been searching for a replacement rear cell.



--
.~. Jean-David Beyer Registered Linux User 85642.
/V\ PGP-Key: 9A2FC99A Registered Machine 241939.
/( )\ Shrewsbury, New Jersey http://counter.li.org
^^-^^ 12:20:01 up 24 days, 20:55, 3 users, load average: 4.74, 4.81, 4.76
On Feb 9, 11:41 pm, "Richard Knoppow" wrote:

If its a standard Triplet the back cell will be a single
lens so there is no need to remove the glass. The front cell
will have two elements. Usually in larger lenses there is a
threaded back cap on the cell but it may have a retaining
ring on the front which is more common for smaller lenses.
If a back cap its easy to remove. The elements are clamped
between concentric edges in the cell so are automatically
centered.
If the cap is too tight for removal with simple finger
grip use one of those rubber jar grippers. It won't mar the
surface. If you grip too tightly it will clamp it and make
it even harder to remove.
I agree with the others about cleaning but if the lens
is oily the standard optical cleaner is pure acetone
followed by dry isopropyl alcohol. Window cleaner like
Windex may streak the lens if not followed by alcohol. The
newer butyl alcohol "streak-free" cleaners are better.
While ammonia is alkaline and strong alkalies can
dissolve some kinds of glass there is no real danger from
the very dilte ammonia in Windex and similar cleaners.
If you use acetone be careful of the edge paint, if any,
and of the paint on the cell because it will dissolve both.
I do not recommend cleaning inside elements when in a
shutter because there is too much danger of getting the
cleaning fluid into the shutter, take the cell out.

--
--
Richard Knoppow
Los Angeles, CA, USA


I'm not absolutely certain about the Geronar formula. It is reported
to be a Tessar.
That said, the rear should be a single piece of glass. But it is not.
If it is a cemented piece, then it is not a true Tessar and the
fogging may be in the cement.
That would be bad.
I've not found the formula out there to describe the lens.
In the mean time I've been searching for a replacement rear cell.


I thought a Tessar had four elements, the rearmost was a cemented doublet.

--
.~. Jean-David Beyer Registered Linux User 85642.
/V\ PGP-Key: 9A2FC99A Registered Machine 241939.
/( )\ Shrewsbury, New Jersey http://counter.li.org
^^-^^ 12:20:01 up 24 days, 20:55, 3 users, load average: 4.74, 4.81, 4.76

[email protected] February 13th 11 06:36 AM

Lens Cell Cleaning
 
On 2/12/2011 12:33 PM, Jean-David Beyer wrote:

Cheesehead wrote:
I'm not absolutely certain about the Geronar formula. It is reported
to be a Tessar.
That said, the rear should be a single piece of glass. But it is not.
If it is a cemented piece, then it is not a true Tessar and the
fogging may be in the cement.
That would be bad.
I've not found the formula out there to describe the lens.
In the mean time I've been searching for a replacement rear cell.


I thought a Tessar had four elements, the rearmost was a cemented doublet.


Lot of confusion in this thread..

A 210mm f6.8 Geronar -IS- a triplet. The rodenstock sales booklet at the
time these were sold stated this.

http://www.bhphotovideo.com/c/produc...nar_Copal.html

A tessar has a cemented doublet but this lens isn't a tessar.

http://en.wikipedia.org/wiki/Tessar

Someone along the way may have swapped out the rear cell from some other
lens into the sample he has or something odd, I have no idea. Maybe he
is confusing a coating problem with fogging inside the cell? I have no
idea on that either.. But the rear cell on a normal 210mm f6.8 geronar
is a single piece of glass.

Stephey





Richard Knoppow February 13th 11 08:22 PM

Lens Cell Cleaning
 
Lots of snipping here................................

"Jean-David Beyer" wrote in message
...
Cheesehead wrote:
Cheesehead wrote:
On Feb 9, 11:41 pm, "Richard Knoppow"
wrote:

I'm not absolutely certain about the Geronar formula. It
is reported
to be a Tessar.
That said, the rear should be a single piece of glass.
But it is not.
If it is a cemented piece, then it is not a true Tessar
and the
fogging may be in the cement.
That would be bad.
I've not found the formula out there to describe the
lens.
In the mean time I've been searching for a replacement
rear cell.


I thought a Tessar had four elements, the rearmost was a
cemented doublet.

--
.~. Jean-David Beyer Registered Linux User
85642.
/V\ PGP-Key: 9A2FC99A Registered Machine
241939.
/( )\ Shrewsbury, New Jersey http://counter.li.org
^^-^^ 12:20:01 up 24 days, 20:55, 3 users, load average:
4.74, 4.81, 4.76


That is correct except that it is possible to have a
"reversed" Tessar with the cemented component in the front.
Also, some Tessar types have the iris in the front air space
instead of the rear even though the cemented component is in
the back.
However, the Geronar is a Cooke Triplet, a
three-element, air-apaced lens with no cemented surfaces.
Its of high quality and such lenses are capable of good
performance at moderate stops.


--
--
Richard Knoppow
Los Angeles, CA, USA




[email protected] February 14th 11 04:39 AM

Lens Cell Cleaning
 
On 2/13/2011 3:22 PM, Richard Knoppow wrote:

However, the Geronar is a Cooke Triplet, a
three-element, air-apaced lens with no cemented surfaces.
Its of high quality and such lenses are capable of good
performance at moderate stops.


From my use, it's a very nice lens given a bad rap mainly because it
was sold at a low price as a "novice lens". Who wants that when you can
buy a pro lens? :P

It's multicoated, comes in a modern, reliable shutter and is
small/lightweight. It actually folds up in my super graphic.

Given most LF lenses are used around f22, the wide open edge performance
isn't an issue for most people. I've actually done some portraits with
mine on 4X5 at f11 and they look great. The only disadvantage I see with
this lens is the smaller image circle compared to the much
Larger/heavier/more expensive plasmat types. If I had to choose this
over some vintage lens that has questionable coatings and flaky/ancient
shutter, I would get this one in a heartbeat.

Stephey



[email protected] February 14th 11 06:04 PM

Lens Cell Cleaning
 
On 2/14/2011 8:37 AM, Cheesehead wrote:


Thanks all.
It looks like my understanding of this lens is in error and that the
rear cell needs to be replaced.
Bummer.



Honestly, you're probably better off just getting another lens. From
what I've seen these don't sell for a lot of money and I'm not sure
where you would even find a replacement rear cell. Maybe find one with a
smashed filter ring or damaged front element (so you can use the one you
have) if you are looking for a cheap way out?

Stephey

Thor Lancelot Simon February 14th 11 07:32 PM

Lens Cell Cleaning
 
In article ,
wrote:

From my use, it's a very nice lens given a bad rap mainly because it
was sold at a low price as a "novice lens". Who wants that when you can
buy a pro lens? :P


Well, at least in the 1990s when the question arose for me, it was more
like "who wants that when you can buy a nice clean used Commercial Ektar"?

Though, actually, knowing what I know now, I'd have gone for a 203/7.7
or a WF Ektar instead, if I were shopping in the Geronar price range
and could only afford one lens.

I suspect most of these that were ever sold were sold with the
Calumet/Cambo kits that bundled them with a moderately priced monorail
camera. I learned with exactly such a kit and it was perfectly good.
But when it came time to buy my own equipment I was strongly advised to
buy a quality used lens instead of a new Geronar, and I think that was
the right advice to give.

--
Thor Lancelot Simon


"We cannot usually in social life pursue a single value or a single moral
aim, untroubled by the need to compromise with others." - H.L.A. Hart

David Nebenzahl February 14th 11 07:58 PM

Lens Cell Cleaning
 
On 2/14/2011 5:37 AM Cheesehead spake thus:

Thanks all.
It looks like my understanding of this lens is in error and that the
rear cell needs to be replaced.
Bummer.


Whoa just one second. Before you toss the lens, let me bug you just one
more time.

It seems to have been established that that rear cell is a single
element, not a cemented doublet. In which case any fogging would
actually be on the surfaces(s) of the cell, not internal.

What did you use to clean the lens? Maybe you need to try something
stronger, like acetone, which can dissolve just about any kind of crud.

Might be worthwhile, even if, as others have pointed out, the lens is
not that great: at least you'd have something to shoot with in the meantime.


--
The phrase "jump the shark" itself jumped the shark about a decade ago.

- Usenet

[email protected] February 14th 11 11:57 PM

Lens Cell Cleaning
 
On 2/14/2011 2:32 PM, Thor Lancelot Simon wrote:
In ,
wrote:

From my use, it's a very nice lens given a bad rap mainly because it
was sold at a low price as a "novice lens". Who wants that when you can
buy a pro lens? :P


Well, at least in the 1990s when the question arose for me, it was more
like "who wants that when you can buy a nice clean used Commercial Ektar"?


I actually replaced a "nice clean" commercial ektar of the same length
with this lens and got much better results at my shooting apertures of
f16-f22. Maybe my sample was a bad one but the geronar has much higher
contrast and "snappyness" to the pictures, especially in difficult
lighting. Add to that a much better shutter, I don't think I'd want 50
year old lens with marginal coatings in one of those old supermatic
shutters over this one.

Like I said, this lens gets a bad rap and I suspect most of the people
saying this have never tested or even used one..

David Nebenzahl February 15th 11 01:52 AM

Lens Cell Cleaning
 
On 2/14/2011 3:57 PM spake thus:

On 2/14/2011 2:32 PM, Thor Lancelot Simon wrote:

In ,
wrote:

From my use, it's a very nice lens given a bad rap mainly because
it was sold at a low price as a "novice lens". Who wants that
when you can buy a pro lens? :P


Well, at least in the 1990s when the question arose for me, it was
more like "who wants that when you can buy a nice clean used
Commercial Ektar"?


I actually replaced a "nice clean" commercial ektar of the same length
with this lens and got much better results at my shooting apertures of
f16-f22. Maybe my sample was a bad one but the geronar has much higher
contrast and "snappyness" to the pictures, especially in difficult
lighting. Add to that a much better shutter, I don't think I'd want 50
year old lens with marginal coatings in one of those old supermatic
shutters over this one.


What do you mean, "marginal coatings"? Do you think they flake off or
something?

Sorry, but it sounds to me as if you've bought the marketing hype hook,
line and sinker when it comes to "advanced, space-age" coatings. The
only "marginal" here is that modren coatings are marginally better than
the old ones. Hell, even *uncoated* lenses (horrors!) can perform
extremely well (under certain conditions).


--
The phrase "jump the shark" itself jumped the shark about a decade ago.

- Usenet

[email protected] February 15th 11 06:54 PM

Lens Cell Cleaning
 
On 2/14/2011 8:52 PM, David Nebenzahl wrote:
On 2/14/2011 3:57 PM spake thus:

On 2/14/2011 2:32 PM, Thor Lancelot Simon wrote:

In ,
wrote:

From my use, it's a very nice lens given a bad rap mainly because
it was sold at a low price as a "novice lens". Who wants that
when you can buy a pro lens? :P

Well, at least in the 1990s when the question arose for me, it was
more like "who wants that when you can buy a nice clean used
Commercial Ektar"?


I actually replaced a "nice clean" commercial ektar of the same length
with this lens and got much better results at my shooting apertures of
f16-f22. Maybe my sample was a bad one but the geronar has much higher
contrast and "snappyness" to the pictures, especially in difficult
lighting. Add to that a much better shutter, I don't think I'd want 50
year old lens with marginal coatings in one of those old supermatic
shutters over this one.


What do you mean, "marginal coatings"? Do you think they flake off or
something?

Sorry, but it sounds to me as if you've bought the marketing hype hook,
line and sinker when it comes to "advanced, space-age" coatings. The
only "marginal" here is that modren coatings are marginally better than
the old ones. Hell, even *uncoated* lenses (horrors!) can perform
extremely well (under certain conditions).




I guess you missed the "difficult lighting? And yes those early coatings
were good, just not as good as later ones. And yes I do use uncoated
lenses too so understand your point here. In tough lighting the ektar
created low contrast chromes.

I didn't make this judgment based on marketing. I wouldn't have bought
a geronar at all if I wasn't having issues with the commercial ektar of
the same length. I have a 135mm WF ektar and the images it makes are
nice and crisp compared to the ones I was getting with the comm ektar,
hence I looked for a replacement. I have never considered replacing the
135mm WF ektar, it works just fine so don't thing older coating are rubbish.

Sorry if posting that -in my experience- this "novice" lens performs
much better that my old commercial ektar did- rocks the boat of people
who are sold on those old lenses are somehow some sort of religious
experience. I could see nothing wrong looking at the commercial ektar,
maybe it was a bad one? I can only base this on my experience. It was a
-sharp- lens but didn't have the contrast/snappyness this geronar has.
So to say "-Blank- old lens is a better choice" didn't work out for me.

Stephey

Richard Knoppow February 16th 11 01:18 AM

Lens Cell Cleaning
 

wrote in message
...
On 2/13/2011 3:22 PM, Richard Knoppow wrote:

However, the Geronar is a Cooke Triplet, a
three-element, air-apaced lens with no cemented surfaces.
Its of high quality and such lenses are capable of good
performance at moderate stops.


From my use, it's a very nice lens given a bad rap mainly
because it was sold at a low price as a "novice lens". Who
wants that when you can buy a pro lens? :P

It's multicoated, comes in a modern, reliable shutter and
is small/lightweight. It actually folds up in my super
graphic.

Given most LF lenses are used around f22, the wide open
edge performance isn't an issue for most people. I've
actually done some portraits with mine on 4X5 at f11 and
they look great. The only disadvantage I see with this
lens is the smaller image circle compared to the much
Larger/heavier/more expensive plasmat types. If I had to
choose this over some vintage lens that has questionable
coatings and flaky/ancient shutter, I would get this one
in a heartbeat.

Stephey

A carefully designed Triplet is capable of excellent
performance and Rodenstock is noted for making good lenses.
I am not sureprized it works well. Somewhere around f/22 is
the "optimum" stop for many LF lenses. The limit of a
Triplet is that they are hard to correct for either high
speed or wide angle, if it isn't required to be either it
can perform entirely satisfactorily.


--
--
Richard Knoppow
Los Angeles, CA, USA




Richard Knoppow February 16th 11 01:24 AM

Lens Cell Cleaning
 

wrote in message
...
On 2/14/2011 8:52 PM, David Nebenzahl wrote:
On 2/14/2011 3:57 PM spake thus:

On 2/14/2011 2:32 PM, Thor Lancelot Simon wrote:

In ,
wrote:

From my use, it's a very nice lens given a bad rap
mainly because
it was sold at a low price as a "novice lens". Who
wants that
when you can buy a pro lens? :P

Well, at least in the 1990s when the question arose for
me, it was
more like "who wants that when you can buy a nice clean
used
Commercial Ektar"?

I actually replaced a "nice clean" commercial ektar of
the same length
with this lens and got much better results at my
shooting apertures of
f16-f22. Maybe my sample was a bad one but the geronar
has much higher
contrast and "snappyness" to the pictures, especially in
difficult
lighting. Add to that a much better shutter, I don't
think I'd want 50
year old lens with marginal coatings in one of those old
supermatic
shutters over this one.


What do you mean, "marginal coatings"? Do you think they
flake off or
something?

Sorry, but it sounds to me as if you've bought the
marketing hype hook,
line and sinker when it comes to "advanced, space-age"
coatings. The
only "marginal" here is that modren coatings are
marginally better than
the old ones. Hell, even *uncoated* lenses (horrors!) can
perform
extremely well (under certain conditions).




I guess you missed the "difficult lighting? And yes those
early coatings were good, just not as good as later ones.
And yes I do use uncoated lenses too so understand your
point here. In tough lighting the ektar created low
contrast chromes.

I didn't make this judgment based on marketing. I
wouldn't have bought a geronar at all if I wasn't having
issues with the commercial ektar of the same length. I
have a 135mm WF ektar and the images it makes are nice and
crisp compared to the ones I was getting with the comm
ektar, hence I looked for a replacement. I have never
considered replacing the 135mm WF ektar, it works just
fine so don't thing older coating are rubbish.

Sorry if posting that -in my experience- this "novice"
lens performs much better that my old commercial ektar
did- rocks the boat of people who are sold on those old
lenses are somehow some sort of religious experience. I
could see nothing wrong looking at the commercial ektar,
maybe it was a bad one? I can only base this on my
experience. It was a -sharp- lens but didn't have the
contrast/snappyness this geronar has. So to say "-Blank-
old lens is a better choice" didn't work out for me.

Stephey


Both the Geronar and Commercial Ektar have the same
number of glass-air surfaces, six. Neither is a high flare
lens even uncoated. Multiple coating does reduce flare and
has much better anti-flare properties for color than a
single coating. The effect is more for color purity and
saturation than for overall contrast.
While its possible the coatings account for the
difference I think something else must be happening. What I
suspect is that the cement in the rear element of the Ektar
may have become hazy. This is a peculiar effect that I've
seen in other Ektar lenses. When examined under
magnification, and using grazing incidence light, you can
see that the cement layer has developed a sort of
orange-peel texture. You can see it using transmitted light
as a light haze but its effect on contrast is enormous.
Check your Ektar for this.
FWIW, the Commercial Ektars were designed especially for
color work and are almost apochromatic. Kodak was using them
to promote the sale of color film.



--
Richard Knoppow
Los Angeles
WB6KBL




[email protected] February 16th 11 05:09 PM

Lens Cell Cleaning
 
On 2/15/2011 8:24 PM, Richard Knoppow wrote:

While its possible the coatings account for the
difference I think something else must be happening. What I
suspect is that the cement in the rear element of the Ektar
may have become hazy. This is a peculiar effect that I've
seen in other Ektar lenses. When examined under
magnification, and using grazing incidence light, you can
see that the cement layer has developed a sort of
orange-peel texture. You can see it using transmitted light
as a light haze but its effect on contrast is enormous.


I used the wrong term saying "marginal coatings", this was more what I
was referring to and since I sold this lens long ago, I have no way to
know what the actual problem was. The other issue I had was right after
purchase I had to have the old shutter repaired. Like I stated in
another post, I love my 135 WF ektar so it's not like I hate old lenses..

I guess what I was trying to get across is: in my experience this
"novice" lens produced MUCH better results, especially on color slide
film, than my commercial ektar did so some statement that one of these
old "classics" is always a better choice didn't pan out for me. Nor have
I seen anything in the results from this lens that would have me go look
for a replacement. Whatever was wrong with that ektar lens wasn't
obvious but I don't doubt there was likely something like you stated
wrong with it. Given their age, I also wouldn't doubt others have this
same issue, that doesn't sound easy or cheap to resolve. I would suspect
that finding a good working sample of a geronar would be more likely
that finding a good sample of a lens that is many years older, YMMV.

Stephey

Richard Knoppow February 17th 11 07:32 AM

Lens Cell Cleaning
 

wrote in message
...
On 2/15/2011 8:24 PM, Richard Knoppow wrote:

While its possible the coatings account for the
difference I think something else must be happening. What
I
suspect is that the cement in the rear element of the
Ektar
may have become hazy. This is a peculiar effect that I've
seen in other Ektar lenses. When examined under
magnification, and using grazing incidence light, you can
see that the cement layer has developed a sort of
orange-peel texture. You can see it using transmitted
light
as a light haze but its effect on contrast is enormous.


I used the wrong term saying "marginal coatings", this was
more what I was referring to and since I sold this lens
long ago, I have no way to know what the actual problem
was. The other issue I had was right after purchase I had
to have the old shutter repaired. Like I stated in another
post, I love my 135 WF ektar so it's not like I hate old
lenses..

I guess what I was trying to get across is: in my
experience this "novice" lens produced MUCH better
results, especially on color slide film, than my
commercial ektar did so some statement that one of these
old "classics" is always a better choice didn't pan out
for me. Nor have I seen anything in the results from this
lens that would have me go look for a replacement.
Whatever was wrong with that ektar lens wasn't obvious but
I don't doubt there was likely something like you stated
wrong with it. Given their age, I also wouldn't doubt
others have this same issue, that doesn't sound easy or
cheap to resolve. I would suspect that finding a good
working sample of a geronar would be more likely that
finding a good sample of a lens that is many years older,
YMMV.

Stephey


Well, results is what counts! It would be interesting
to know if the Ektar had something wrong with it. Coating in
general should not affect sharpness so but does affect
contrast and color purity and saturation, all of which are
interepreted by the eye as sharpness. OTOH, its possible
that this Geronal is just a better lens than the Commercial
Ektar you had.
If your Wide-Field Ektar has satisfactory contrast and
color rendering its a good indication that the problem with
the C-E was not the coating. The WF Ektar has the same
coating plus it has _four_ glass-air surfaces.


--
--
Richard Knoppow
Los Angeles, CA, USA




[email protected] February 17th 11 05:23 PM

Lens Cell Cleaning
 
On 2/17/2011 2:32 AM, Richard Knoppow wrote:
If your Wide-Field Ektar has satisfactory contrast and
color rendering its a good indication that the problem with
the C-E was not the coating. The WF Ektar has the same
coating plus it has _four_ glass-air surfaces.



That's true and I do use a LOT of cameras from that time period with
single coated and even uncoated lenses so I'm not sure what the issue was.

Another experience, I ran into the same sort of problem with a 135mm
xenar LF lens. It was a -horrible- lens where the 75mm xenar on my
rolleicord is a wonderful one. So just because a lens has more elements
in my experience doesn't mean it's always a better performer.

Stephe


David Nebenzahl February 17th 11 06:47 PM

Lens Cell Cleaning
 
On 2/17/2011 9:23 AM spake thus:

On 2/17/2011 2:32 AM, Richard Knoppow wrote:

If your Wide-Field Ektar has satisfactory contrast and color
rendering its a good indication that the problem with the C-E was
not the coating. The WF Ektar has the same coating plus it has
_four_ glass-air surfaces.


That's true and I do use a LOT of cameras from that time period with
single coated and even uncoated lenses so I'm not sure what the issue was.

Another experience, I ran into the same sort of problem with a 135mm
xenar LF lens. It was a -horrible- lens where the 75mm xenar on my
rolleicord is a wonderful one. So just because a lens has more elements
in my experience doesn't mean it's always a better performer.


Well, that particular lens seems to have a universally bad reputation,
based on what I've read and on at least one actual experience (not me,
but someone else who had one and didn't like it). Strange, since the
name "Xenar" usually denotes exceptionally high quality, at least in
other forms ...


--
The phrase "jump the shark" itself jumped the shark about a decade ago.

- Usenet

Richard Knoppow February 17th 11 10:04 PM

Lens Cell Cleaning
 

wrote in message
...
On 2/17/2011 2:32 AM, Richard Knoppow wrote:
If your Wide-Field Ektar has satisfactory contrast
and
color rendering its a good indication that the problem
with
the C-E was not the coating. The WF Ektar has the same
coating plus it has _four_ glass-air surfaces.



That's true and I do use a LOT of cameras from that time
period with single coated and even uncoated lenses so I'm
not sure what the issue was.

Another experience, I ran into the same sort of problem
with a 135mm xenar LF lens. It was a -horrible- lens where
the 75mm xenar on my rolleicord is a wonderful one. So
just because a lens has more elements in my experience
doesn't mean it's always a better performer.

Stephe

I had a chance to test a 135mm, f4.5 Xenar as supplied
on some Speed Graphics, it had a problem similar to the
Wollensak Raptar/Optar in that while the center was quite
sharp the corners never got completely sharp even when
stopped down all the way. This problem seems to be uniform
throughout the Rapar/Optar line, including the enlarging
lenses, but not for the f/5.6 lens made for the Graflex
Super-D or the Wollensak telephoto lenses, both of which are
very good. I also have Rollei cameras with f/3.5 Xenars and
they are extremely sharp with good corner performance. All I
can think is that the same prescription was not used for
other focal lengths or for other speeds. Its very odd. So, I
don't know if you got a dog or if all of the Xenars are that
bad.
More elements give the designer more resources to make
corrections. The Cooke Triplet has six surfaces, two
spacings, and three powers, just enough to correct all seven
of the primary aberrations and maintain focal length. More
complex lenses allow for correction of secondary aberrations
so they are valuable where one needs a faster or wider angle
lens. Also, by using a symmetrical design the lateral
aberrations, lateral color, coma, geometrical distortion,
are, at least to some degree automatically corrected by the
symmetry.
While the Triplet is a simple lens it is _not_ cheap to
make because the element spacing is very critical so that
the mount has to be precision made.
The Tessar was not inspired by the Triplet but the
Heliar was. Hans Harting, of Voigtlander, tried to correct
some of the secondary aberrations of the Triplet by
compounding the two end elements. His original design was
not successful but later designers did much better. The
Voigtlander Heliar (which became a different design than
Harting's original), the Dalmeyer Pentac (of Booth), and the
Kodak Ektar used on the Medalist camera, and the Kodak
Enlarging Ektar lenses of 50mm and 75mm are examples of
excellent lenses based on this general design. However,
other lens types offer more possibilities to the designer so
the Heliar type has not been popular.


--
--
Richard Knoppow
Los Angeles, CA, USA




Thor Lancelot Simon February 18th 11 03:11 AM

Lens Cell Cleaning
 
In article ,
wrote:

Another experience, I ran into the same sort of problem with a 135mm
xenar LF lens. It was a -horrible- lens where the 75mm xenar on my
rolleicord is a wonderful one. So just because a lens has more elements
in my experience doesn't mean it's always a better performer.


Most LF Xenars were "press" lenses, which really means budget: small
circle of coverage, never the best coatings (newspaper printing amps
up the contrast plenty), in some cases questionable quality control.
Schneider had a much higher-end series of lenses for similar applications,
the Xenotar. Perhaps this is has something to do with why the Xenars
are so uncharacteristically bad for Tessar formula lenses in those
lengths.

On the other hand, maybe it's not "uncharacteristic". Wollensak made
some awful Tessar lenses and so did a few others. Maybe Richard knows:
is there something about the Tessar design that makes is particularly
prone to manufacturing or Q/C error?

There are some truly awful Schneider large format lenses as well as some
very good ones. The 90 and 120mm Angulons in particular seem to have
been either misdesigned or systematically mismanufactured, while by
the time they started multicoating (for example, the earliest Symmar-S-MC
lenses) they seem to have gotten their act together.

The Schneider web site says they made the large-format Xenars until
the mid 1990s (this is a surprise to me). I wonder if the later ones
were any better.

--
Thor Lancelot Simon


"We cannot usually in social life pursue a single value or a single moral
aim, untroubled by the need to compromise with others." - H.L.A. Hart

Donn Cave February 18th 11 10:15 PM

Lens Cell Cleaning
 
Quoth (Thor Lancelot Simon):
....
| On the other hand, maybe it's not "uncharacteristic". Wollensak made
| some awful Tessar lenses and so did a few others. Maybe Richard knows:
| is there something about the Tessar design that makes is particularly
| prone to manufacturing or Q/C error?

I believe one way to make a Tessar awful is to use it for LF
applications that require a larger circle than it really delivers.

While comparing the reputations of various Tessars, it might be
interesting to correlate with the absolute coverage circle -
that's not the right word, I mean the farthest extent of any
kind of coverage, irrespective of optical quality. My hunch
is that identical glass could have a better or worse reputation
depending on artificial cutoff from its mounting etc.

I was always more interested in tonal rendering, something I used
to read about with various lens types though couldn't positively
pick out of my own results. It seemed to me for example that
my 20" Calumet-Ilex (Tessar type I believe) turned out better
on color negative film than a 10" WF Ektar or a MC 240mm Caltar-S.
Not a conspicuous difference at all, and I didn't get real
scientific about it, but enough that I would use the Calumet-Ilex
when I could.

Donn

David Nebenzahl February 18th 11 11:53 PM

Lens Cell Cleaning
 
On 2/18/2011 2:15 PM Donn Cave spake thus:

Quoth (Thor Lancelot Simon):
...
| On the other hand, maybe it's not "uncharacteristic". Wollensak made
| some awful Tessar lenses and so did a few others. Maybe Richard knows:
| is there something about the Tessar design that makes is particularly
| prone to manufacturing or Q/C error?

I believe one way to make a Tessar awful is to use it for LF
applications that require a larger circle than it really delivers.

While comparing the reputations of various Tessars, it might be
interesting to correlate with the absolute coverage circle -
that's not the right word, I mean the farthest extent of any
kind of coverage, irrespective of optical quality. My hunch
is that identical glass could have a better or worse reputation
depending on artificial cutoff from its mounting etc.


Interesting you should mention coverage as it relates to Tessars.

Some time ago I did an experiment (a successful one as it turned out)
with a Tessar that was "too short" for the format. Not sure it qualifies
as LF, but I was shooting 9x12 (cm) film with the "next smaller size"
lens, a 105mm (made for 6x9) instead of the usual 135mm or so. (The lens
was a Carl Zeiss Jena f/4.5 Tessar).

It covered beautifully, sharp and tasty looking from corner to corner.
Not an extreme example, I'll grant you: the 9x12 image circle is 150 mm
(nominal), while the 6x9 is 110 mm. And I believe that these older,
uncoated lenses are exceptionally well-made, high-quality examples of
the species.


--
The phrase "jump the shark" itself jumped the shark about a decade ago.

- Usenet

Nicholas O. Lindan February 19th 11 12:43 AM

Lens Cell Cleaning
 
"Thor Lancelot Simon" wrote

The Schneider web site says they made the large-format Xenars until
the mid 1990s (this is a surprise to me). I wonder if the later ones
were any better.


If the mid 80's sample I had was anything to go by the later LF Xenars
were every bit as horrible as Schneider's earlier output.

Quality of Angulons was probably worse, but some rather good
samples did manage to escape the factory.

--
Nicholas O. Lindan, Cleveland, Ohio
Darkroom Automation: F-Stop Timers, Enlarging Meters
http://www.darkroomautomation.com/da-main.htm
n o lindan at ix dot netcom dot com



[email protected] February 19th 11 02:10 AM

Lens Cell Cleaning
 
On 2/18/2011 5:15 PM, Donn Cave wrote:
Quoth (Thor Lancelot Simon):
...
| On the other hand, maybe it's not "uncharacteristic". Wollensak made
| some awful Tessar lenses and so did a few others. Maybe Richard knows:
| is there something about the Tessar design that makes is particularly
| prone to manufacturing or Q/C error?

I believe one way to make a Tessar awful is to use it for LF
applications that require a larger circle than it really delivers.



The xenar I am talking about looks bad on 6X9. A 135mm tessar should
easily cover that sharply when stopped down. This one won't.

Stephey

David Nebenzahl February 19th 11 03:00 AM

Lens Cell Cleaning
 
On 2/18/2011 6:10 PM spake thus:

On 2/18/2011 5:15 PM, Donn Cave wrote:

Quoth
(Thor Lancelot Simon): ...

On the other hand, maybe it's not "uncharacteristic". Wollensak
made some awful Tessar lenses and so did a few others. Maybe
Richard knows: is there something about the Tessar design that
makes is particularly prone to manufacturing or Q/C error?


I believe one way to make a Tessar awful is to use it for LF
applications that require a larger circle than it really delivers.


The xenar I am talking about looks bad on 6X9. A 135mm tessar should
easily cover that sharply when stopped down. This one won't.


I guess some lenses are just born bad ...


--
The phrase "jump the shark" itself jumped the shark about a decade ago.

- Usenet

Richard Knoppow February 21st 11 06:06 AM

Lens Cell Cleaning
 

"Nicholas O. Lindan" wrote in message
m...
"Thor Lancelot Simon" wrote

The Schneider web site says they made the large-format
Xenars until
the mid 1990s (this is a surprise to me). I wonder if
the later ones
were any better.


If the mid 80's sample I had was anything to go by the
later LF Xenars
were every bit as horrible as Schneider's earlier output.

Quality of Angulons was probably worse, but some rather
good
samples did manage to escape the factory.

--
Nicholas O. Lindan, Cleveland, Ohio
Darkroom Automation: F-Stop Timers, Enlarging Meters
http://www.darkroomautomation.com/da-main.htm
n o lindan at ix dot netcom dot com


I have a prototype Angulon, its awful. It has severe
color fringing, something a lens of this type should not
have at all. My lens designer friend tell me that the
prescription in the patent shows up pretty bad when set up
in a lens optimization program. Later Angulons do not seem
to have this problem so it must have been changed in some
way. The Angulon is similar to a Dagor but uses a different
order of powers in the cells. It also has some power shifted
from being exactly symmetrical to improve its correction for
distant objects. It should be no worse than a W.A.Dagor but
it is. Originally Schneider claimed 105 degree coverage. In
fact, the lens has a circle of illumination that large but
the image quality beyond about 90 degrees is pretty bad. The
Dagor claims 97 degees but also isn't good beyond about 90
even the WA Dagor. Modern WA lenses are much better than
these things but are also much larger and heavier.
My impression is that Schneider was not a quality brand
before 1945 but their lenses after that were very good to
excellent. However, I've checked a couple of f/4.5 or f4.7
Xenars for Speed/Crown Graphics which showed excessive
something, maybe coma or maybe oblique spherical aberration
leading to smearing of highlights away from the center. This
is very similar to the problem with Wollensak Raptar/Optar
lenses for press cameras. Even when stopped down to f/32 the
marginal image is not sharp.


--
--
Richard Knoppow
Los Angeles, CA, USA




Nicholas O. Lindan February 21st 11 08:55 PM

Lens Cell Cleaning
 
"Richard Knoppow" wrote
I have a prototype Angulon, its awful.


The two good samples I have had were both 'Linhoff' branded on the shutter
and were late production.

--
Nicholas O. Lindan, Cleveland, Ohio
Darkroom Automation: F-Stop Timers, Enlarging Meters
http://www.darkroomautomation.com/da-main.htm
n o lindan at ix dot netcom dot com



[email protected] February 22nd 11 12:05 AM

Lens Cell Cleaning
 
On 2/21/2011 3:55 PM, Nicholas O. Lindan wrote:
"Richard wrote
I have a prototype Angulon, its awful.


The two good samples I have had were both 'Linhoff' branded on the shutter
and were late production.



The 135mm xenar I had was in a linhoff shutter too. It was abysmal..


Stephey

Thor Lancelot Simon February 22nd 11 04:47 PM

Lens Cell Cleaning
 
In article ,
Nicholas O. Lindan wrote:
"Richard Knoppow" wrote
I have a prototype Angulon, its awful.


The two good samples I have had were both 'Linhoff' branded on the shutter
and were late production.


Interesting. I had a 90mm Angulon which I would characterize as just
barely acceptable -- but not truly awful like the contemporaneous 120mm
Angulon I tried around the same time. Mine too said "Linhof" on the
shutter.

I know at some point Linhof started doing very stringent re-QA on
every lens they sold. Supposedly they duplicated the entire QA
setup that Rodenstock used at the end of their production line, and
supposedly they did actually reject some lenses that had passed
manufacturer QA (though it is not clear whether this means the
manufacturer had actually tested the lenses that failed, or just a
statistically significant sample of lenses from the same run). I
wonder if this was because of spotty quality from one or more suppliers
earlier on.

--
Thor Lancelot Simon

"We cannot usually in social life pursue a single value or a single moral
aim, untroubled by the need to compromise with others." - H.L.A. Hart

[email protected] February 22nd 11 07:06 PM

Lens Cell Cleaning
 
On 2/22/2011 11:47 AM, Thor Lancelot Simon wrote:
In [email protected] .com,
Nicholas O. wrote:
"Richard wrote
I have a prototype Angulon, its awful.


The two good samples I have had were both 'Linhoff' branded on the shutter
and were late production.


Interesting. I had a 90mm Angulon which I would characterize as just
barely acceptable -- but not truly awful like the contemporaneous 120mm
Angulon I tried around the same time. Mine too said "Linhof" on the
shutter.

I know at some point Linhof started doing very stringent re-QA on
every lens they sold. Supposedly they duplicated the entire QA
setup that Rodenstock used at the end of their production line, and
supposedly they did actually reject some lenses that had passed
manufacturer QA (though it is not clear whether this means the
manufacturer had actually tested the lenses that failed, or just a
statistically significant sample of lenses from the same run). I
wonder if this was because of spotty quality from one or more suppliers
earlier on.



I have heard this same thing but question this given the 135mm xenar I
had, that was horrid, was in a linhof shutter. Obviously some other lens
other than the original one could have been put in this shutter by
someone along the way to make it appear to be a better lens than it was.
I suppose seeing the linhof brand on a shutter could help "prove" it's a
good sample but given the age and unknown history, it's not a fact cut
in stone anymore.

Stephey

Thor Lancelot Simon February 22nd 11 09:09 PM

Lens Cell Cleaning
 
In article ,
wrote:

I suppose seeing the linhof brand on a shutter could help "prove" it's a
good sample but given the age and unknown history, it's not a fact cut
in stone anymore.


Right. At one point in the mid-90s, the Linhof factory rep for the
U.S. used to very loudly hold forth here about the special Rodenstock
testing machine Linhof had acquired for this purpose, etc. etc. -- but
then again, he was also the Rodenstock factory rep.

He didn't typically respond to questions about what might be wrong with
Rodenstock's own quality control such that Linhof felt they needed to
repeat it! (Of course, this was a little unfair, since Linhof did not
relabel *only* Rodenstock lenses... but it was fun to yank the guy's
chain.)

I suspect Linhof was badly burned by questionable lenses at some point
and decided on this testing program to reduce warranty costs or brand
image problems. That would imply that after some point, Linhof-marked
lenses were particularly good, while before that time, they may well
have been particularly bad.

Since for Linhof's main competitor, there were always both budget
(Wollensak) and premium (Kodak) lenses available, someone having an
awful experience with a Raptar was not likely to abandon the Graphic
or Graflex cameras entirely. But if Linhof was getting all or most
of their lenses from Schneider at some point and Schneider was churning
out Xenars of poor quality -- which seems to have been the case! -- then
they would need some way to escape the damage this could do their brand.

--
Thor Lancelot Simon


"We cannot usually in social life pursue a single value or a single moral
aim, untroubled by the need to compromise with others." - H.L.A. Hart

Richard Knoppow February 23rd 11 03:14 AM

Lens Cell Cleaning
 

"Thor Lancelot Simon" wrote in message
...
In article ,
wrote:

I suppose seeing the linhof brand on a shutter could help
"prove" it's a
good sample but given the age and unknown history, it's
not a fact cut
in stone anymore.


Right. At one point in the mid-90s, the Linhof factory
rep for the
U.S. used to very loudly hold forth here about the special
Rodenstock
testing machine Linhof had acquired for this purpose, etc.
etc. -- but
then again, he was also the Rodenstock factory rep.

He didn't typically respond to questions about what might
be wrong with
Rodenstock's own quality control such that Linhof felt
they needed to
repeat it! (Of course, this was a little unfair, since
Linhof did not
relabel *only* Rodenstock lenses... but it was fun to yank
the guy's
chain.)

I suspect Linhof was badly burned by questionable lenses
at some point
and decided on this testing program to reduce warranty
costs or brand
image problems. That would imply that after some point,
Linhof-marked
lenses were particularly good, while before that time,
they may well
have been particularly bad.

Since for Linhof's main competitor, there were always both
budget
(Wollensak) and premium (Kodak) lenses available, someone
having an
awful experience with a Raptar was not likely to abandon
the Graphic
or Graflex cameras entirely. But if Linhof was getting
all or most
of their lenses from Schneider at some point and Schneider
was churning
out Xenars of poor quality -- which seems to have been the
case! -- then
they would need some way to escape the damage this could
do their brand.

--
Thor Lancelot Simon


The curious thing is that Wollensak's prices were no
lower than Kodak's for their "premium" lenses. I think there
was some sort of design blunder made on the design for the
Raptar/Optar lenses used on press cameras and the Enlarging
Raptar lenses, which are also pretty bad. Kodak's Ektar
lenses are uniformly excellent as are the Enlarging Ektars.
Even Ilex lenses, also not cheap by any means were head and
shoulders better than Wollensak. Now, another curiosity is
that the Optar lenses made by Wollensak for the Series-D
Graflex are excellent. A different design even though still
a Tessar. They were offered as an alternative to the Ektar
lenses for these cameras but the price was about the same.
I think Wollensak got the reputation for being cheap
because they made a lot of OEM lenses for cheap cameras. So
did Ilex for that matter.
Wollensak shutters OTOH are excellent and, since they
use all hair-springs, can be rebuilt with new parts.


--
--
Richard Knoppow
Los Angeles, CA, USA





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