What is causing this Flare?

rogue_designer

rogue_designer

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This is a puzzler. I have an occasional flare with the new to me M4-2... It seems to happen more on bright shots, but not always. I need to double check older ones to see if it is only when there is a specular reflection in the frame (or a very bright sidewalk/lower half of the frame).

Is it the film rail? The gate? Something else? Is there an easy cure.

Any thoughts are appreciated.

m42_flare.jpg
 
same happens on my M3 if i leave the cap off for a few minutes... i replaced the shutter with an aftermarket one and i suspect that its thin-ness is the reason.
 


I get this occasionally, maybe one frame in 500, usually when the sun is high in the sky in front of the lens, it seems not to matter if the lens itself is in the shade, as it was in this shot.

Had it for years I’ve never found the reason, swapped lenses, doors bodies but still find odd ones spoiled, I’ve just resigned myself to “stray reflections” but let me know if you find a reason.
 
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I've had exactly the same on my M2. In my case it was caused by a worn/loose strip of felt at the back of the light baffle, which should keep the film gate light-tight.

Remove the lens and open the back door. Keep the lens mount against a bright light source and look from the back side. You will see light peeping along the upper or lower long side of the film gate, especially when cocking the shutter.
There are felt strips along the lower and upper side of the light baffle; they both could cause problems. In my case this flare only showed up where I changed lenses.
For a qualified repairman it was an easy fix.
 
Blank288 said:
I've had exactly the same on my M2. In my case it was caused by a worn/loose strip of felt at the back of the light baffle, which should keep the film gate light-tight.

Remove the lens and open the back door. Keep the lens mount against a bright light source and look from the back side. You will see light peeping along the upper or lower long side of the film gate, especially when cocking the shutter.
There are felt strips along the lower and upper side of the light baffle; they both could cause problems. In my case this flare only showed up where I changed lenses.
For a qualified repairman it was an easy fix.
Click to expand...

If that were the case wouldn’t you expect the flare to go out to the edge of the frame? As the gutter that the shutter’s light-trap is in is actually outside of the frame not overlapping it as the examples show.
 
I had this on several M3 bodies. Most likely it is caused by stretched or warped shutter curtains, or as said above, the foam / felt seal. The foam seal is easy enough to fix for a competent tech but the shutter is a different story. You'll have to send it to DAG or someone like it. It is sometimes really hard to notice, even if you look really hard at the curtains themselves. Also, it could happen in either the uncocked or cocked position. You'll need to do some tests.

Both times it happened to me it was deemed uneconomical to repair seeing as I live in New Zealand and by the time the camera was fixed and shipped I could have bought a near mint M6 for the same money. One body had it really bad and the other was only of minor concern. Funny enough the more pretty one was the worst and my beat up 'ol faithful was the pick of the two to use.
 
TJV said:
I had this on several M3 bodies. Most likely it is caused by stretched or warped shutter curtains, or as said above, the foam / felt seal. The foam seal is easy enough to fix for a competent tech but the shutter is a different story. You'll have to send it to DAG or someone like it. It is sometimes really hard to notice, even if you look really hard at the curtains themselves. Also, it could happen in either the uncocked or cocked position. You'll need to do some tests.

Both times it happened to me it was deemed uneconomical to repair seeing as I live in New Zealand and by the time the camera was fixed and shipped I could have bought a near mint M6 for the same money. One body had it really bad and the other was only of minor concern. Funny enough the more pretty one was the worst and my beat up 'ol faithful was the pick of the two to use.
Click to expand...

Please explain why, if that is the case, the flare doesn’t go out to the edge of the frame?
 
Doesn't sound like there is clear consensus..

No changing of lenses going on... but I'll watch for that just to see.

I guess I need to keep shooting for a bit, to see if I can narrow down a pattern better. I'm hoping its something I can deal with myself. I hate having to send out for repairs.
 
The sun is behind you, so it could be a leak in the lower part of the back door. Some Leicas have seals in the door, should be easy to replace.

I have seen this when shooting almost directly into the sun and thought it was the shadow of the hood at high f stops. You do have a strong reflection of the sun in the car window.

Roland.
 
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ferider said:
The sun is behind you, so it could be a leak in the lower part of the back door. Some Leicas have seals in the door, should be easy to replace.

I have seen this when shooting almost directly into the sun and thought it was the shadow of the hood at high f stops. You do have a strong reflection of the sun in the car window.

Roland.
Click to expand...

Yes but that would then be the bottom edge of the door and the seal is along the hinge.
 
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Sparrow said:
Please explain why, if that is the case, the flare doesn’t go out to the edge of the frame?
Click to expand...

Well - this challenges my English language competence a bit - in my case the curtains could run/sit just a bit too far to the front side of the camera; thus stray light allowing to pass underneath the curtain. Since the film gate is about 1mm thick, and the film plane is kept back a little bit further by the inner film rail, in my case this most likely caused a small 'shadow' rim in the flare area. Just as the sharp edge in the examples presented above.
I could see this happen, and a fix of the felt rims and/or adjustment of the light shroud indeed cured the issue. I don't remember what my repairman exactly did - except that it was a very quick fix.

I think back door issues would cause fogging on upper or lower perforation areas too.
 
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Troubleshoot this by capping the lens, removing the film door, pointing the camera at a bright light source, and peering through from the back where the fog appears on the negative. Do this with the shutter open (on B) and closed. Move the camera about and see if the leak becomes obvious.

There are many light shields and they can shift. It's an easy fix for a repair person but they need help in location before they spend a lot of time trying to find it.

An M2 of mine suffered a similar defect only occasionally, and was a light shield under the top plate.
 
I tried that, and couldn’t see anything, I have a few bodies and I suspect they all do it certainly one has m6 maylar traps on the gutters that were fitted last year.

I also tried shining a photoflood directly into the lens for half an hour then firing the shutter with the lens cap on, and then on the next frame doing the same on the back around the door to see if I could fog the film that way.

It isn’t a problem for me as it happens so infrequently I’m just interested in how it happens

I hadn’t thought about the top plate, I suppose it could be coming that way in freak conditions
 
I got this kind of flare on my Canon 20D with the 17-40 a few times. I never bothered to notice why, but it is odd how it ends on such a hard line. Also a few times that I have shot movies now that I think of it....this happened when I was shooting a documentary and we were in a studio with bright light coming through windows and the top of the frame would have this type of flare too.
 
It looks like a light leak not flare. It could be coming from behind, the edge on the top is too hard and it's not across the entire frame.

How often does it happen? Is there something different you can remember, about setting down the camera, walking in bright sun, not taking pictures for a long time between frames, taking the camera out of a case, did you take a half case off?

B2 (;->
 
As it was explained to me by a Wetzlar trained Leica technician, the foam seal by the back door is not a light trap. The design of the door is such that there's a physical baffle that keeps light from getting anywhere near the film. It would have to make a couple of sharp corners before hitting the film.

Then there's the pressure plate which is parked on top of the film.

I'm inclined to think shutter issues. Is it possible the shutter curtain was replaced previously and the cloth is not really light tight ?
 
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