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Tim Layton
8-Oct-2019, 06:19
Hi, I would like to know the opinon of the large format community about Schneider lenses that are effected by "Schneideritis".

Do you feel there are any optical issues associated with this condition?

Is the lens worth less because of it?

I appreciate your thoughts.

Tim

BrianShaw
8-Oct-2019, 06:47
No effect on images. “Worth less” depends on if your buying, selling, using, or collecting.

Tim Layton
8-Oct-2019, 06:51
Thanks Brian. I have one to sell and one that I want to buy, so I would like input on both scenarios.

Thanks



No effect on images. “Worth less” depends on if your buying, selling, using, or collecting.

Pere Casals
8-Oct-2019, 06:57
It's a cosmetic issue, no impact.

The barrel inside is black to prevent any stray light generation from rays ending thete, so in theory those "white spots" may generate some stray light, but if you inspect the open lens from the ground glass position you won't see much any spots, in any case they are not bright to be a concern, and at the usual shooting apertures I guess it would be really difficult for any ray reflected in the "spots" to reach the film.

IMHO Schneideritis has no impact in the image, and if it's able to generate a minuscle flare amount this is much, much, much smaller that the flare generated in other ways.

IMHO, anyway, it has no sense being concerned by Schneideritis while not using a very well adjusted compendium shade, which would generate hundreds or thousands times more flare.

Tin Can
8-Oct-2019, 07:07
What about internal dust production...

Pere Casals
8-Oct-2019, 07:15
What about internal dust production...

Randy, Schneideritis is not produced in the barrel wall that is in contact with air, it is produced in the side of the glass that is in contact with the barrel, no paint is released... simply those are spots in the lens side that should be making contact with the barrel and don't. An "optic effect" makes think that problem is in the barrel free wall, but's not like that.

At all, internal haze and internal dust are not related to Schneideritis, IMHO.


To remove Schneideritis we have to remove the group and painting its side... the glass that's touching the barrel.

Tin Can
8-Oct-2019, 07:27
OK

https://www.photrio.com/forum/threads/what-is-schneideritis.18363/

https://www.largeformatphotography.info/forum/showthread.php?9976-Schneideritis

Tim Layton
8-Oct-2019, 07:39
Even if the issue around optical defects is arguable, it would seem logical to me that the value of the lens would be less whether you are a buyer or a seller.

What are your thoughts about that?

eric black
8-Oct-2019, 07:55
as someone who has bought and sold quite a bit on the used market- yes, the price would likely need to be less than a lens with no issues. How much depends I think on the frequency the lens appears on the used market- if you have lots of them available and would like to sell it- you will need to entice the buyer with potentially a significantly lower price. If its appearance on the for sale blocks is less frequent, then IMHO a small decrease in price to maybe no decrease in price may result in a sale.

BrianShaw
8-Oct-2019, 08:00
Thanks Brian. I have one to sell and one that I want to buy, so I would like input on both scenarios.

Thanks

Generally speaking I’ve observed: Lower selling price; lower buying price.

Pere Casals
8-Oct-2019, 08:11
Even if the issue around optical defects is arguable, it would seem logical to me that the value of the lens would be less whether you are a buyer or a seller.

What are your thoughts about that?


I've been happy to buy lenses with Schneideritis because they were cheaper, very happy... at the same price I'd take the one with the best cosmetics... of course.


Here it's shown that Schneider is not alone, also it's seen that the spots are in the inside of the coating applied to the bevel of the lens perimeter, and not generating dust:

196315

196316

196317

https://www.rangefinderforum.com/forums/showthread.php?t=158580


To repair it that coating in the bevel has to be sanded and black paint applied again, but no work is required in the barrel itself. Painting only the bevel solves nothing, as problem is in the inside, the original paint has to be eliminated to reach the spots that are in contact with glass, under black coating.

The real problem is a lens coming without shneideritis but with a faulty shutter :)

BrianShaw
8-Oct-2019, 08:21
I’ve seen it in a Fuji lens too.

Internal dust is not a significant problem.

neil poulsen
8-Oct-2019, 08:57
Alternate opinion . . .

I would not purchase a lens with this affliction, at least, not a lens that had this problem in any significant quantity. Think about it, all that BRIGHT LIGHT bouncing around. Even multi-coated elements reflect some amount of light. So, some of that reflected light is bound to make it to shadow areas in a scene. And, I HATE FLARE! This ill effect could only be enhanced with single-coated optics.

It's absolutely offensive. I have a 180mm lens with Schneideritis, and when I can so afford, it will be replaced.

Pere Casals
8-Oct-2019, 09:32
It's absolutely offensive. I have a 180mm lens with Schneideritis, and when I can so afford, it will be replaced.

Neil, you may do something, measure flare from the lens with schneideritis and the one without it, Ctein explains how this can be done. You won't be the first one checking that.

It's always good to know if replacing a lens was justified.

Jac@stafford.net
8-Oct-2019, 10:22
Even if the issue around optical defects is arguable, it would seem logical to me that the value of the lens would be less whether you are a buyer or a seller.

What are your thoughts about that?

Last Christmas my wife and I did our mutual shopping. We visited a car dealer first and after she had shaken decorative boughs, driven demos through snow, had cookies and coffee, I bought her a new hybrid, then we were off to a photo shop looking for a lens for me. We were jolly-silly browsing large-format goodies hugged by giant pandas and when we got to a display of Schneiders she exclaimed quietly, "Ooooh, Christmas globes!", picked one up and gave it a twist and shake. "No show. You think they make them like this for Christmas or some other irrational rationale?"

RedGreenBlue
8-Oct-2019, 14:10
I've always been curious if anyone has removed the cells and repainted them?

Pere Casals
8-Oct-2019, 17:18
I've always been curious if anyone has removed the cells and repainted them?

Yes... see this:

https://richardhaw.com/2016/11/12/repair-shneideritis-edge-separation/
https://web.archive.org/web/20190503211128/https://richardhaw.com/2016/11/12/repair-shneideritis-edge-separation/

If having to disassemble the lens to remove internal inter-group haze or dust, or to fix a separation then it's easy to also fix Schneideritis.

But IMHO it's silly disassembling the glass groups for Schneideritis only, as it has no impact in the images. To me, it only makes sense if it's a really expensive lens and you want to sell it. Me, as a buyer, I would prefer the Schneideritis than a lens that has been disassembled, but the seller may think different, as he has not to say if it has been disassembled.

Jim Galli
8-Oct-2019, 18:35
Schneider Kreuznach would not replace lenses for this. They're the ones who said it has no effect. A friend of mine recently sold a gazillion dollar Cooke 945 that had this happening and his buyer went nutso on him and made him pay return shipping as well as refund. He didn't even know it was there. Totally surprised, and I believe him. So on very high dollar stuff it can be a problem. On ubiquitous Schneider 210 plasmats . . . ignorance reigns. I've bought 210mm Schneiders with a good dose of Schneider-itis for $95 bucks to rob the Copal 1 shutter recently.

Mark Sampson
8-Oct-2019, 19:50
One would like to see the results of any tests that compare similar optics with, and without, "Schneideritis". I'd also want to know the methodology of such tests. Since no one has ever been able to show that "Schneideritis" causes any image degradation, I doubt that we will ever see any such test results.

One result that I'm sure of is that it's an issue for some buyers and sellers of used gear, not for people making photographs.

I am reminded (from my Leica days) of some people who were certain that the Leitz lenses made in Midland, Canada, were inferior to those made in Wetzlar, Germany. Why? "well they just have to be- they weren't made in Germany!" There was no reasoning with those people, and I soon learned to avoid them.

Pere Casals
9-Oct-2019, 02:56
I'd also want to know the methodology of such tests.

A practical test is quite easy, just take the camera and point to an scene with a very high brightness range and meter deep shadows vs mids with a probe in the GG, compare the reading with lenses of same model and with and without the "itis". Do what you want, you won't find a difference. Comparing "vs mids" is important to overcome aperture calibration.

In any case the light reflected by the film itself and bounced back by the bellows inside (that it is black only in theory), or bounced back by the lensboard rear (also black only in theory), will be much, much higher. Then add all the image circle that do not hits the film and bounces rays around, if not using a very tight compendium shade.

If being aware of all that, speaking about the "itis" effect has no sense. At least it's totally LOL speaking about the "itis" while not using the compendium shade.

Tin Can
9-Oct-2019, 05:44
Germans strive for perfection

I cannot decide if 'itis is primarily schadenfreude

neil poulsen
9-Oct-2019, 07:05
Neil, you may do something, measure flare from the lens with schneideritis and the one without it, Ctein explains how this can be done. You won't be the first one checking that.

It's always good to know if replacing a lens was justified.

I have to admit, my reasoning is "based" on conjecture.

But, it sure sounds darn'd reasonable to me. :)

Pere Casals
9-Oct-2019, 07:30
I have to admit, my reasoning is "based" on conjecture.

But, it sure sounds darn'd reasonable to me. :)



Nothing like a new glass ! me too :)

Havoc
9-Oct-2019, 11:25
Nothing like a new glass ! me too :)

Those sodium and other atoms are probably billions of years old.

Pere Casals
9-Oct-2019, 13:10
Those sodium and other atoms are probably billions of years old.

Good point !