Haze in lens

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I have bought a 25 years old G-Claron. It looks pretty clean from the outside but when looking through to a bulb, there is some haze on the sealed surfaces of the elements. How much will this affect the lens contrast, and is a cleaning up something affordable?

-- Paul Schilliger (pschilliger@vtx.ch), May 19, 2000


I am curious about this too. What makes a lens get hazy?

-- William Marderness (wmarderness@hotmail.com), May 19, 2000.

Paul: In all probability the haze will have no effect on your pictures. In the days of uncoated lenses, the haze actually increased contrast and cut glare. Make some test shots and see if it doesn't work o.k. If the haze bugs you, it shouldn't be expensive to have the lens cells cleaned. Good shooting, Doug.

-- Doug Paramore (dougmary@alanet.com), May 19, 2000.


Get the lens cleaned. Haze is a sure way to kill contrast.

I managed to clean up a 210mm Fujinon W and 210mm APO Lanthar using Windex - common ammonia based household window cleaner (a perfect haze and fungus remover).

The main issue is opening up (or how to open up) the lens. If you're not comfortable with doing it yourself, send it to a workshop. Can't cost much to get haze cleaned.

G-Clarons are bitingly sharp lenses.

-- K H Tan (kahheng@pacific.net.sg), May 19, 2000.

Doug, I think you are referring to natural 'blooming' or lens tarnishing, which has a contrast increasing effect, not haze. Haze effectively lowers contrast, not increase it.

-- K H Tan (kahheng@pacific.net.sg), May 19, 2000.

Not all haze is created equal. The G-Claron is coated but not multi-coated and the haze you see (at that age) can most likely be easily removed with simple disassembly and cleaning--but if you have never done it, it's best left to a professional! Make some exposures before and after cleaning to compare, you may be surprised. Many believe that coating mostly improves optical performance but another function is to prevent premature tarnish or oxidation of the glass surface. Doug (who knows his stuff) mentions this type of haze which many call "bloom" and which is largely associated with uncoated glass. The bloom condition in aging uncoated glass was discovered to improve lens speed and led to the creation of modern coating methods. Some lenses get internal haze as the metal and paint compounds within the casing slowly age, this is most likely the G-Claron's trouble and should clean up nicely. I've paid $40 to $80 for top-notch service.

-- C. W. Dean (cwdean@erols.com), May 19, 2000.


Point taken about the terminology. I have always thought that "tarnish" was tarnish and "haze" was haze. I did not realise that there haze could mean tarnish as well.

-- K H Tan (kahheng@pacific.net.sg), May 19, 2000.

If it appears hazy when looking through it then it ain't "bloom." Bloom shows up like a spotty reflection on a lens surface. If you're lucky it is from fumes coming from an excessively lubricated shutter. These can be cleaned with ordinary lens cleaner, and should not be inside a lens element. Otherwise it is lens cement which has slightly crystalized from getting too hot at some time, and you are screwed.

-- Bill Mitchell (bmitch@home.com), May 19, 2000.

Paul: I am a firm believer in doing repairs on my own lenses, including a bit of shutter repair and cleaning on my shutters, but disassembling a lens cell is another matter. It can be done, but without the proper tools you will probably chew up the retaining rings and can do damage to the glass. Some of the interior glass is quite fragile. It can be scratched easily and shatters with too much pressure or uneven pressure. The elements also need to be centered when the lens is reassembled for maximum sharpness. As I said, it can be done, but you need to know what you are doing. There is definatly risk that you can screw up a good lens. Good shooting, Doug.

-- Doug Paramore (dougmary@alanet.com), May 19, 2000.


About a year ago I discovered a similar haze inside the front element of my older 210 Symmar S. As far as I could tell, it did not have any adverse effect on my images, but it bothered me nontheless.

I thought it would just be simple cleaning job, so I brought it to a local lens repair person here (a certified Nikon repair center). He took the front cell apart and cleaned the haze off.

A few months later the haze started to come back. I then called Steve Grimes and he told me to send the cell to him. He called me back and told me it was some sort of "outgassing" inside the lens elements, not a fungus, and not caused by moisture, incorrect storage or ill-treatment.

He said many Schneider lenses suffered from this problem. He said he uses a chemical treatment to clean the haze off, and also "sealed" the interior of the lens to prevent future outgassing/haze. Only charged me $50.

And he also advised me the first repairman had slightly damaged the very delicate coating on the lens element(s) when he tried to physically wipe off the haze. Grimes said he does not wipe off the haze, he soaks it in the chemical to remove the haze; the coatings on the earlier Schneider lenses was quite soft.

Now the lens looks crystal clear. Grimes has my business from now on. Very nice man to deal with, prompt and professional.

Hope this helps. Good luck, Sergio.

-- Sergio Ortega (s.ortega@worldnet.att.net), May 20, 2000.

Wow, isen't this Forum a fantastic knoledgebase? Reading all your contributions helped me to determine that what I saw into the lens whas "bloom". It is not visible when looking through the lens, but it appears as tiny spots or dust (crystals?) when lookink to a dark surface with a bright source of incident light (bulb) nearby. Should I not worry about it? Anyway, I took it for a serie of shots, outside, and the chromes are contrasty and very sharp. Thank you! By the way, the G-Claron I have is coated, but are the current G-Claron multicoated?

-- Paul Schilliger (pschilliger@vtx.ch), May 23, 2000.

Don' woory n bee hapi.

-- Bill Mitchell (bmitch@home.com), May 23, 2000.


If you're happy with the results, leave it alone?

To the best of my knowledge, the G Clarons have only been single coated, even those you find new in shutters today.

I haven't exactly been the most careful with blocking stray light with a hood, but the results from my lens (1969-70 vintage 240mm version) have been excellent to date. Good contrast, supersharp corner to corner results at f22 @ infinity. Color balance is fairly neutral and matches my later Schneiders very well.

I have managed to locate two in barrel mounts (a 150mm and a 210mm) recently and when I get them, I will screw them into the shutters which my late Fujinons of the same focal lengths are occupying. I have been looking forward to owning a 150mm G Claron for 1:1 still life work for the longest time.

There are sometimes excellent deals on the barrel mounted versions of these lenses and they are worth picking up since all the G Clarons to date (bar the Wide Angle version) can be used in standard size 0 (150mm),1 (210mm - 305mm) or 3 (355mm) shutters with no expensive modifications. Just use a vernier caliper to ascertain that the length of the lens is about the same in barrel and in shutter, and transfer all shims that came with them.

These are really excellent lightweight lenses to carry round.

BTW Paul, there is a lot of discussion about the G Claron lenses at Ron Wisners Q&A Archives - http://www.wisner.com/archive.htm He seems to recommend these lenses highly even though they fall into the budget Schneider line (after the excellent Xenars). Mr Wisner suggests that Schneider specs are a little too conservative and that the lenses do cover a LOT more than is officially stated (e.g., the 210mm and the 240mm cover 8x10 at f45). He also considers them the modern version of the Dagor.

-- K H Tan (kahheng@pacific.net.sg), May 27, 2000.

Thanks! I thought you would be interested by some tests I have made recently. Some Times ago, I switched from my flatbed Technika to a VX 125 Monorail. Subsequently, I started to notice soft images resulting from the use of my Fujinon C 300. When an inexpensive barrel Claron presented, I thought this was the opportunity to have a close-up lens to fit my Fujinon shutter, and in the same time, to have a comparison lens for the Fujinon performances. So I made comparison shots, using the more stable Tech, with four of my lenses, shooting a lens testing chart on 6x9 rollfilm, with a distance of 3 to 5m to keep the same image size, all takings at 1sec. f16. This was a "real situation" test, not a "scientific" lens test. It took into account the camera stability as well as the lens qualities at an average lens stop. The Xenar 210 probably made the sharpest shot (with some color warming up though) followed with almost unnoticeable sharpness difference by the Fujinon C300 (both lenses are from the last decade). Then comes a forty years old Apo-Ronar 360 on Compur 3, still very sharp, and last, with noticeable difference, the 25 years old G-Claron. This test reassured me on the Fujinon quality, and showed again the importance of camera stability with long lenses. The Fujinon is better than the G-Claron? I'm not sure. Maybe at working apertures of f22-32, things could have changed and showed the Claron more favorably. Also, a different shutter speed could have modified the scores: the G-Claron weighs much more than the Fujinon and therefore can perhaps induce a sway. And my test took into account the center performances only: What about the corners of an 8x10" image? Working distance is another factor: I secondly shoot a piece of canvas at 1:5 and the G-Claron image is tack sharp. An objective testing would have supposed several shots at different openings, lens mounted on a very stable optic bench. The purpose of this one was to reassure me on the quality of the recently acquired Fujinon and this was attained! I will now have to work on camera stability to ensure consistent sharpness in the field! The Toyo VX125 is at it's weakest point with a 300 mm and the slightest breeze will ruin the picture sharpness. The Technika in this, is superior and shows much more stability in the field. ...Perfection still isn't from this world!

-- Paul Schilliger (pschilliger@vtx.ch), May 30, 2000.

Well, after reviewing on the comparisons tests, I had an other look at the slides and, to both my good surprise and greatest embarrassment, I discovered a very sharp corner on the test slide made with the G-Claron! So, unless there is a misalignment of the elements in this lens, there has been a film flatness problem in this test. Since there is no trash possibility for my previous post, I apologize and correct this in here.

-- Paul Schilliger (pschilliger@vtx.ch), May 30, 2000.

Paul, use of a roll film holder was the most likely source of problems with your test. Such holders all put a reverse curl on the film, which manifests itself as a bulge towards the lens after it's advanced to the image area. Frame 1 is capable of great sharpness, but subsequent exposures can suffer from film plane mispositioning of up to 0.03" over a significant region. My solution when performing critical work like your comparison is to use only the odd frames on a roll. I expose #1, then advance quickly past #2 and stop at #3, etc. That way segments of film which took a set on the reverse curl roller are never within an image.

-- Sal Santamaura (bc_hill@qwestinternet.net), May 30, 2000.

Thanks Sal, good tip on rollfilm use! I would normally use 220 type film and have good results with it, but I made the test with a 120, and I had noticed previously that it sometimes pop's up, perhaps due to the paper pressure. I will test it anew.

-- Paul Schilliger (pschilliger@smile.ch), June 01, 2000.

Paul, there should be no difference between 120 and 220 regarding the reverse curl/bulge problem. They both suffer from it; paper pressure doesn't seem to make matters any worse compared to the longer paperless variety. Unless, of course, your 220 back is a vacuum type!

-- Sal Santamaura (bc_hill@qwestinternet.net), June 01, 2000.

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