dark spots on all bulb shutter exposures M2

[ericdan]

Hi,

I took a few long exposures with the shutter speed dial set to bulb mode.
Every frame captures that way had a weird dark spot in the lower left corner.
I took the lens off and opened the back of the camera over a light table in a dark room to check for holes in the curtain but can't see anything.
any ideas?
attached are a few samle images.

 

[Lachlan Young]

From what I recall, there's a couple of odd places light can leak in on M-series cameras (for some reason the rewind release & self-timer pop into my mind) - and it may not be a significant leak at 1/250, but over a few seconds, it's enough to fog the film. Whatever it is, I'd be having a close look at the top right of the film gate - I don't think it's the shutter or back.

 

[ericdan]

From what I recall, there's a couple of odd places light can leak in on M-series cameras (for some reason the rewind release & self-timer pop into my mind) - and it may not be a significant leak at 1/250, but over a few seconds, it's enough to fog the film. Whatever it is, I'd be having a close look at the top right of the film gate - I don't think it's the shutter or back.

thanks a lot. will check that.
if it is the back, wouldn't it then also ruin other frames? not only the bulb shutter ones?

 

[beemermark]

UFO? Maybe a pin whole leak small small it only shows up on really long exposures?

 

[ericdan]

Yes. The weird thing or maybe not is that the frames before where 60 mins exposures but at night. No leaks there. The daytime ones with the leak were 3-4mins each.

 

[gone]

Black spots on the negative would mean issues w/ the emulsion, right? Maybe processing problems if the chemicals weren't fully mixed? I've never had this problem.

 

[ericdan]

Black spots on the negative would mean issues w/ the emulsion, right? Maybe processing problems if the chemicals weren't fully mixed? I've never had this problem.

thank for the input, but I think the chances are negligible.
Only on long exposures and only during daylight on exactly the same spot on different rolls?

 

[MattKing]

It could even be a reflection off a lens hood or a cable release - something that won't manifest itself except when light levels are moderately high, and exposures are moderately long.
But I would bet on a light leak near the top right somewhere that is normally of no effect except when the shutter is open for a long time.

 

[Lachlan Young]

But I would bet on a light leak near the top right somewhere that is normally of no effect except when the shutter is open for a long time.

This seems like the most probable cause.

 

[Huss]

That is a light leak through the RF window. It happened on my M5 and looked just like that. Zachs camera repair fixed it.
There is a thread on it.

W/ yours, it is very slight which is why it only shows up on bulb pictures.

 

[ericdan]

That is a light leak through the RF window. It happened on my M5 and looked just like that. Zachs camera repair fixed it.
There is a thread on it.

W/ yours, it is very slight which is why it only shows up on bulb pictures.

Thank you sir!

just got my other roll of slide film back. Shot same way on my other m2 with a Zeiss lens. Same problem but in the lower right. Seems to be. An inherent issue with Leicas. Need to tape up the rangefinder window just like SLR shooters tape up the viewfinder window. I guess…?!

 

[film_man]

Thank you sir!

just got my other roll of slide film back. Shot same way on my other m2 with a Zeiss lens. Same problem but in the lower right. Seems to be. An inherent issue with Leicas. Need to tape up the rangefinder window just like SLR shooters tape up the viewfinder window. I guess…?!

The leak will only get worse though over time...no? So better get it fixed till it starts showing up in normal exposures?

 

[250swb]

The most probable cause is a leak in the top right corner of the rear door (image projected back to front and upside down), the top edge of the door is the only part of the rear door that has a felt light seal. Unclip the rear door and see if it's intact across the whole width. One thing that does occur to me with your long exposures, you have one negative without a leak, so are you using a torch to fiddle with camera settings? Maybe that is your culprit?

 

[Huss]

The most probable cause is a leak in the top right corner of the rear door (image projected back to front and upside down), the top edge of the door is the only part of the rear door that has a felt light seal. Unclip the rear door and see if it's intact across the whole width. One thing that does occur to me with your long exposures, you have one negative without a leak, so are you using a torch to fiddle with camera settings? Maybe that is your culprit?

Nope because it would also be outside the image frame into the film rebate.

 

[bernard_L]

Yes. The weird thing or maybe not is that the frames before where 60 mins exposures but at night. No leaks there. The daytime ones with the leak were 3-4mins each.

No weird. By definition (?) a leak does not care whether the shutter is open or not. What matters is the intensity of ambient light. So it makes sense that the night-time exposure shows no leak. Keep in mind, also depends on when the film is advanced. If you take a night exposure, do not advance film, then have your camera in sunlight, probably you will see the leak in the night exposure frame.
The logic above fails in case it is a parasitic reflection rather than a leak.