Banding with M7

[pphuang]

Hello, long time lurker, first time poster. I've learned a lot following the threads on this great site, and need some advice.

I shoot with an M7, and have noticed a funny banding problem on some of my photos. This tends to occur at the beginning or end of a roll of film, but more frequently at the end. I don't recall ever seeing it happen in the middle of a roll of film. I'm attaching some files to show the problem. All of these are shot with a 35 lux. test1 and test2 are shot with tmax, and test3-6 are shot with provia 400vc. These are straight scans with no retouching - sorry for all the dust and hair marks.

test3-6 are the last four frames on this particular roll - you can see that test3 looks fine, test4-5 look funky, and then test6 looks a little better, but still odd.

Thanks for any ideas - I often see it on one or two frames on each roll of film, and it's driving me crazy. If I wanted banding, I would have bought an M8! 😀

 

[pphuang]

And here's the other 3 files.

 

[gavinlg]

uh oh... Looks like a shutter issue to me (although I could be wrong)

If it is a shutter issue, you'll be up for a CLA. The shutter in leica M's isn't as accurate and doesn't stay as accurate as say... an SLR shutter.

Thanks,
Gavin

 

[pphuang]

Thanks Gavin, that would make sense - maybe its sticking or something...

 

[StuartR]

If it was a shutter issue, I would have expected to see a bit more uniformity (I.E. evenness from top to bottom), so my guess is some sort of light leak or problem with the internal light baffles. Anyway, either way it looks like a CLA is in order. The only other thing I can suggest is that you shoot another roll and try a different lab. If the same problem occurs at a different lab, there is definitely something happening on the camera end, and it needs some help.

 

[sepiareverb]

The diagonal fog might suggest a pinhole in the shutter? I would think a sluggish curtain would leave a vertical mark. There's been a few threads about burning a hole in the shutter curtain- search 'burn' and see the examples posted there.

 

[rogue_designer]

have you detected any pattern? ie. all slow shutter speed shots? all AE?

Anything at all that might have been different about the ones that get borked?

The angle of the band makes me think it's not necessarily shutter related, but I don't know what else it might be.

 

[Edward Felcher]

That's a light leak in the base of the camera.

Or much less likely, a too-small lens hood.


PS: It also could be light getting into the cartridge, either caused by you or the lab.

That's not what is generally described as "banding", which the dolts imagine seeing in all their digital files. That's light hitting the film.

 

[kbg32]

First, who does your film processing and scanning? Try a different lab, if that doesn't cure the problem, then have the camera checked.

 

[kinoglass]

Does not look like a shutter problem. It seems like film exposed during loading or processing. Body light leak possible but unlike. You should look at the film in its full width not just at the frame area. If the film edges are exposed following the pattern apearing on the frame area you can assume film handling problems as the source of the fogging.

 

[ray_g]

Does not look like a shutter problem. It seems like film exposed during loading or processing. Body light leak possible but unlike. You should look at the film in its full width not just at the frame area. If the film edges are exposed following the pattern apearing on the frame area you can assume film handling problems as the source of the fogging.

That is correct. I had an M3 that had a problem with the light baffles, and the streak or banding went across frames, including the film outside the frame areas. If it were a shutter problem, the streaks would likely be limited to the frames.

 

[pphuang]

Thanks all for the good suggestions. If it were a light leak, I would think that you would see it consistently in every frame rather than sporadically. The B&W and color negatives were developed and processed in two different labs in two different states, so I don't think its a lab issue. Its also odd that it tends to happen at the end of the roll, but also sometimes at the beginning. I think I have to do some more systematic testing to try and pin this down, and also take a closer look at the negs - thanks again for all the help...

 

[Xmas]

The rebates and inter frame gaps are the diagnostic, - rebates the area out of the normal frames, the sprocket holes areas and printed on frame number areas.
A leak into the take up chamber volume could give very strange effects.
The flying security x-ray machines give pretty effects like this as well.
You may need to scan a negative strip if these dont help.

Noel