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Jackson
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, September 23, 2004 - 03:13 pm: | 
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I have a GSN that is like new cosmetically. I've replaced the light seals, cleaned various switch contacts, and everything functions well. The only problem I'm experiencing is flare, and lately I've been wondering if it might be due to the internal design. The effect shows up occasionally in photos as a lightening of the print and loss of contrast over a fairly large area extending from the direction of a light source that is outside the field of view.
Is it possible this is the result of insufficient internal light baffles? The front and rear lens surfaces are clean and clear and have no scratches, even under magnification. In addition, I use this with a reasonably large lens shade. The only other thing I can think of is haze on the inner surfaces of the glass, perhaps from solvent evaporation over time. However, I haven't heard of this as a common problem in the Electro rangefinders.
Has anyone here experienced this problem, and if so, is there a cure? |
Jon Goodman
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, September 23, 2004 - 03:21 pm: |
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Hi, Jackson.
Is there any way you can scan a picture to some website or link where I could see one? I have not seen anything like this as a tendency in these cameras, particularly if you are using a lens shade.
Jon |
Jackson
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, September 23, 2004 - 10:49 pm: |
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Jon, here's a quick page I've put up to show two examples of the problem. Please note that I need to delete it within a couple days to save space. Thanks for taking an interest in this!
Yashica GSN Flare |
Jon Goodman
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, September 24, 2004 - 07:53 am: |
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Hi, Jackson.
Well...it is probably the scanner or my monitor, but the first thing I'd say is these pictures look out of focus and underexposed. I am sure the originals are better. Assuming the lens/rangefinder are in agreement (and that the lens/film plane is also in focus), the black & white picture looks to me like it was taken with a lower aperture setting (I am guessing 4 or 5.6), and is basically underexposed by a factor of about 2. This camera does not take filters or hoods into consideration, as the meter takes its reading from outside the filtered area. In 2A, it seems to me the picture was taken indoors (maybe in a market?) with bright light coming from behind the subject...through a window. I think you simply picked up this brightness in your picture...as a strong backlight. This camera should produce very sharp images, and I'm not aware of lens flare problems...at least I've never had any. Because of the metering design, I avoid filters on mine. I'll e:mail you a picture taken with mine so you can see...I am not where I can post it to a host.
Jon |
Jackson
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, September 24, 2004 - 10:30 am: |
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Jon, the problem with 2A is the rectangle of light that partly covers the subject's face. I suspect it's from a light source located out of the field of view. It's purely a reflection or flare from within the camera. There was no direct light like this projected onto the subject. Note that 2A and 3A both contain bright sources within the frames, but 3A doesn't seem to exhibit any abnormality.
Yes, the black and white print is underexposed, but it was shot with the film speed selector set to compensate for the yellow filter (opened one stop from ASA 400 to ASA 200). If memory serves, aperture was set approximately to f/8. The underexposure is the result of this being a backlight situation, shot from within shade. I could have opened up more using the film speed selector, but this was only intended as a test roll. In any event, my concern is for the washed out area in the upper-mid region of the frame. It's reminiscent of the problem in 2A, insofar as it seems to be the result of a light source out of the field of view.
Regarding image quality, the color image is from an index print of thumbnails, and the print simply doesn't possess the necessary resolution to obtain good quality when magnified. The black and white will probably look sharper if you reduce its size on the screen to approximately 4 X 6. Again, these are scans from prints. Image resolution better than 150 dpi or so is wishful thinking. Sorry I can't provide anything better.
Incidentally, the light seal kit is terrific. Thanks a bunch! |
Jon Flanders
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, September 25, 2004 - 04:19 pm: |
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I have experienced flare with the GSN and the Lynx. These are uncoated lenses and in some situations I think that it is to be expected.
I try to avoid shooting towards direct sunlight, and of course use a hood.
The available light capacity and sharp images overall make up for this occasional problem in my book.
Check the shot labeled "Surrounded" in this collection at the rangerfinderforum.com
https://kyp.hauslendale.com/photopost/showgallery.php/cat/500/ppuser/524
Jon Flanders |
Jackson
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, September 25, 2004 - 11:50 pm: |
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Jon, thanks for the information. I didn't realize the GSN lens was uncoated. I thought I remembered seeing a hue when I was working on my first one of these some time back. After reading your post, I went to my work room and reinspected several Yashica lenses. Although light reflected off the GSN lenses doesn't look quite the same color as the source, neither does it look significantly altered. Lenses from a Lynx 5000 and Lynx 5000e have the same characteristic, that is, they appear to be plain glass and exhibit only a slight color shift. So, it appears I've overlooked this important characteristic of these cameras. Oddly, the Lynx 14 I'm currently working on and the spare 14 that's donating parts both have a distinct purplish/blue coating on the front lens element.
Thanks for linking to the photo you shot, entitled "Surrounded." I believe it displays the exact symptom that I'm experiencing. Now, the question is, how certain are you that this is the result of the plain glass lenses in these cameras? Do you think it's possible that it might be due to poor internal baffling? Note that I'm not arguing with your analysis, it's just that I consider this anomaly to be a fatal flaw. If it's due to the lenses (and therefore incurable), I will want to dispose of these cameras. I'm not anxious to do that though, and would be willing to experiment with makeshift foam baffling to see if the problem can be resolved. However, that's time consuming, and I would prefer to obtain more in-depth information from someone knowledgeable first. Anything you could add to all this would be very helpful. For example, have you used other uncoated lenses that produced essentially the same results? Have you noticed this effect with single- or multi-coated lenses?
To be honest, I only have a few reasons for restoring and using these older rangefinders. I've invested the last seven years in assembling an SLR kit, and although it consists of mostly low to medium cost lenses, each is the product of slow and careful analysis based on real-life performance in my hands. Lenses that have failed basic tests or been deemed redundant have been sold or discarded. The result is an overall equipment capability that exceeds my own, and I can easily duplicate or exceed the lens speed and sharpness offered by 35mm fixed-lens rangefinders. However, my SLRs are generally noisy and obtrusive, and candid photos can be exceedingly difficult. These older rangefinders have the potential to remedy that, albeit with a number of tradeoffs. They are also easier to grab for a quick opportunity, and I readily admit, they are also frequently more fun to shoot.
I guess the rangefinder process is going to be similar to building the SLR kit. I'm not really a collector, and that helps quite a bit. I only need to be concerned about models that are genuinely capable shooters. Some will be keepers, others will be weeded out. Given all this, where along the fence does the GSN fall? Is there a cure for the flare you and I have seen, or should I concentrate on models like the Mamiya f/1.5 I recently repaired and the Lynx 14? Does anyone else here have an opinion on this issue? |
Winfried
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 26, 2004 - 03:13 am: |
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I am sorry I have to say this but it is nonsense that the Electro35 and Lynx lenses are uncoated. You can clearly see a dark blue reflection from the surfaces of all these lenses, indicating an antireflective coating.
None of the serious camera manufacturers dared to sell uncoated lenses after the early 50s. However, it seems that the coating of the Electro35 lenses was improved with the introduction of the Color Yashinon lenses which are probably multicoated, and earlier lenses cannot compete with today's high-tech multicoating.
You can see a clear difference between the reflections of a 'real' uncoated lens and one even with poor coating. The uncoated lens will have reflections which seem white, while a coating lens will reflect the light in a different color (usually violet). It is not easy to see this difference with a single light source such as a single bulb, but holding it against a window when the sun is not shining in directly will show.
Older cameras differ significantly in reducing internal reflections between the lens and the film plane. Some use a system of 'fences' with sharp edges and different height, some just use a mat coating of the plane surfaces. But I never had big problems with internal reflections in the camera. |
Howard
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 26, 2004 - 08:47 am: |
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Hi Jackson. In my humble opinion the Yashica GSN/GTN cameras are right on top of the fence. In the world of Japanese 35mm fixed lens rangefinder cameras they are up there with the best. They take beautiful photos and if you are happy with the semi automatic nature of the cameras they are very much a keeper. I also use a Nikon F and a Canon A1 and the Yashica lens matches both those in nearly all respects. I am continually amazed by just how well the photos come out.
I have taken quite a few photos with my GSN and flare has never been a problem, mind you I am mindful of the sun's position. I never use a filter though so perhaps you could try shooting a film without your yellow filter to see if it is somehow the culprit. One other camera I would recommend is the Konica Auto S or S2. Both beautifully made and with very sharp lens and nice built in sliding lens hoods.
Best wishes, Howard. |
Dan Mitchell
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 26, 2004 - 01:12 pm: |
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Like Winfried said all these Yashinon lenses are coated. I just looked at a Lynx 5000 and can see violet, yellow and blue reflections. These lenses are quite good, but here are some problems I have seen.
Hold the shutter open on B and maximum aperture, open the back, and then point the camera at a lamp while looking through the lens. Sometimes you will see a hazy appearance caused by deposits on the inside surfaces of the lens. That can be cleaned off easily by removing the lens from the camera.
If there are a lot of cleaning scratches the lens will go almost "white" from the scattering of light. Cleaning marks don't affect normal picture taking, but with back lit subjects it can cause a lot of loss of contrast. (I've taken pictures with an old Argus A4 that had terrible cleaning marks on it, yet the pictures didn't show any problems.)
You will probably also see dust in the lens. A small amount won't be a problem, but if there is a solid coating of dust stuck to an inner surface that should be cleaned as well.
A filter can cause problems. I had some bad reflections on a Lynx 14 that was caused by the Skylight filter. The filter isn't as good as the coating on the lens, so try taking the filter off and see if there is a difference.
Finally, try using a lens shade. Those big pieces of glass have very little lens barrel in front and light from the side can cause a problem too.
I would also recommend the Konica Auto S2. Fantastic lens on that camera, too!
Good luck. |
Dan Mitchell
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 26, 2004 - 01:15 pm: |
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Oops, I didn't read closely enough. I see you are already using a lens shade! |
Jackson
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 26, 2004 - 10:04 pm: |
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Hi Winfried - I don't know why your lenses would be different, but these are yellow, not blue. After reading your post, I even took several of the lenses outside, just to confirm. Indoors or out, their reflections produce only a yellow cast. I also see no indication that they might be multi-coated. Incidentally, the coating is very light and particularly difficult to discern under incandescent lighting. The Lynx 14 is much different; the coating is darker and immediately recognizable as purplish/blue. The question is, why don't my Yashica GSN lenses look like yours? How visible is the blue coating you're referring to? Does your GSN also exhibit a yellow cast?
Light baffles are a subject I'm somewhat familiar with after examining various cameras during the last few years. The most rigorous treatment I remember was in a Ricoh Diacord L TLR that I used for a few months. The internal baffles consisted of steps, as you mentioned, and the camera took beautiful, high-contrast photos. The Rikenon lens coatings were dark blue and (I believe) multi-coated. As is the case with my SLRs, flare was virtually non-existent in this camera.
Howard, I agree that these cameras can take good photos. I have several frames from my first few rolls that are very sharp and contrasty. The problem is, I apparently can't rely on the camera to do this consistently. I had hoped the problem might be limited to my particular example, but I now see from Jon Flanders' post that I'm not the only user who has experienced this. That worries me. Incidentally, the rectangular reflection in the color photo 2A was produced with no filter. Conversely, the yellow filter used in the b&w frame has produced beautiful results throughout hundreds of shots on other cameras and lenses.
Dan, those are excellent ideas, and I think I've eliminated all but one - internal haze. Here's a question: Do you think it's sufficient to unthread the front group from the lens barrel, then clean the backside of the front group and the front surface of the rear group (directly behind the diaphragm), or should the front and rear groups be disassembled as well? Incidentally, it does confuse me how haze could cause this problem occasionally but not result in all the frames being soft. That was the case with another (older) camera I used for awhile.
Just to help me sum everything up, is it the general consensus that the problems I'm seeing (and the example Jon Flanders posted) are not the result of deficiencies in the design of the GSN? If so, I'll tear into one, clean the glass, and try again. |
Winfried
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 27, 2004 - 12:05 am: |
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I was referring to coated lenses in general, it is true that quite a few do not have a violet or blueish reflection but rather a yellowish or even magenta one.
The reason is that one layer of coating cannot prevent reflections all over the spectrum of visible light rays. So the lens designer has to choose a 'center wavelength' for which reflections are reduced by a maximum, and the other colors of the spectrum will still be reflected more or less.
Most lenses have a coating which is optimized for green light to which our eyes respond very sensitive. Hence the red and the blue part of the spectrum are still reflected, yielding a violet reflection.
I have to admit I did not have a close look at my Electro's when writing my posting. But I remember that the 'normal' Yashinon and the Color-Yashinon differ in colors of reflection, so both cannot be blueish. I think mine has the same color of reflection as yours.
However I never had problems with flare due to poor coating on any camera with coated lenses. And even uncoated lenses (provided they have a low number of glass-to-air surfaces) are better than you might expect. Except for some shots with heavy backlight I got excellent results with an Ikonta with pre-war uncoated Novar lens. The shots I mentioned show heavy flare and sometimes even spots of internal reflections. |
Jon Flanders
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 27, 2004 - 09:14 pm: |
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I think I mis-spoke about lens coating. I meant to say that these lenses are not multi-coated.
Mike Graham in his review says this at
http://www.geocities.com/heidoscop/electro35.htm
"The lens is a high performer that can easily match any non-multicoated SLR prime lenses. Don’t forget, even Nikon didn’t start multicoating their optics until the seventies, a fact that bothered nobody"
Karen Nakamura says about the Yashica GX
"Unfortunately the GX's lens suffers from contrast reducing flare in direct sunlight (backlit situations, etc.). It really needs an auxiliary lens hood. B&H Photo has a $4.95 generic brand rubber hood that will fit the 52mm screw-in filter mount. I tried it but it covers too much of the viewfinder view. So it doesn't look like there's a good way to avoid flare except to not take this camera outdoors in the sun."
At any rate I don't find the occasional flare problem that discouraging, given all the great shots the camera has given me.
Jon Flanders |
Jon Flanders
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, September 28, 2004 - 07:04 pm: |
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This morning I bought the NY Times as usual and what do you know, both pictures on the front page showed signs of flare.
One was in the subway system where there was a fire and massive backups of the trains. The other was a picture which had a window in the background. I assume that the NYT has good photographers with top of the line equipment. Multi-coated lenses. Still, there it was.
http://www.nytimes.com/2004/09/28/nyregion/28penn.html
Jon Flanders |
Jackson
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, September 29, 2004 - 11:10 am: |
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Jon, the flare in this photo is extremely well controlled, much different that what you and I have experienced with the GSN.
Winfried, by coincidence I acquired an early model, pre-GS Electro yesterday. The lens indeed reflects blue. So, somwhere between the early models and the GSN, the coating was changed.
For some reason, I can't get the outer ring off my "good" GSN using a friction disc. I'll make another tool for this over the next few days so I can remove the front glass and clean the inner surfaces. If that doesn't resolve the problem, the GSNs are history. I have too many other cameras (including other single-coated rangefinders) that don't do this. If cleaning does fix this issue, I'll report back.
As always, I have appreciated everyone's opinions and suggestions. The GSN certainly has its strengths, but maybe it's just not a good fit for me. |
David
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 23, 2004 - 10:36 pm: |
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It may seem obvious but flare-like problems can also be caused by a or scratched front lens surface or even by light leaks in the camera back. As has been said before, of course all Electro 35's have coated lenses! |
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