Why am I getting dark edges on my pictures?

Question

I started taking pictures with an Olympus om-4. My film was ISO 800 and I was shooting in bright sunlight so not optimal circumstances. I mostly used shutter speed 2000 and f-stop 2.8-5.6. About half of my pictures has a black edge on the left side of the frame. The other half were perfectly fine. Is there something wrong with the shutter curtain?

Answer 1

If you had shutter capping you'd see a cutoff that's aligned to the frame and straight-edged -- and with this orientation, only with a horizontal travel focal plane shutter. As far as I can see, your OM-4 has a vertical travel shutter (like most metal-curtain types).

What you have here looks more like vignetting from a too-small or misaligned lens shade/hood. If you were using a zoom, it may show only on images taken at the wider end of the zoom range.

One (rather uncommon) way a shutter problem could cause this (especially at very high speeds) is if the two curtain edges are not parallel. This is hard to test (because your eye can't come close to seeing the shutter travel), but many smart phones can shoot "slow motion" -- that is, record video at a higher frame rate and play it back slower, sometimes even frame by frame.

If you have one of these (most better phones newer than 2018 or so should do it) you could (with camera back open) record the shutter travel at maximum frame rate, then examine the recording while running as slowly as you can -- this might let you verify if the leading and trailing curtain edges remain parallel throughout the exposure.

If they do, look elsewhere (hand alongside the lens, maybe, given you say no hood was used) -- if you see them misaligned, however, you may need to have the camera serviced or repaired.

Answer 2

This could have several reasons, which you might want to check.

Film Issues

Is the problem also present on the film negatives? If you are really lucky, the issue was at the printing stage.

Lens Hood

If you are using a wide lens and the lens hood was not seated properly, you can end up with heavy or uneven vignetting.

Shutter Curtains

It could be an issue with the shutter curtain. You should be able to verify that by doing some exposures after finishing and removing your current film roll and doing some clicks with open back. However, if the curtain is fringed or broken, usually you get lighter areas, not darker.

Darker areas would indicate something blocking the view for the whole exposure time. That should be pretty visible on inspection of the shutter mechanism during operation.

If your camera has a shutter that moves sideways, the black area would be an indicator for a stuck part of the shutter curtain mechanism.

Answer 3

The OM-4 used a horizontal cloth focal plane shutter with a manual speed range of one second - 1/2000 second Wikipedia

My guess is it is shutter lag because 1/2000 is at the extreme end of the camera’s range, 1/2000 is toward the higher end of speeds for SLR’s of the era, particularly the era in which the OM series was originally developed.

And because the camera is more than thirty years old and probably hasn’t had full service by an expert technician in some years if ever.

Using slower shutter speeds is the simplest thing that might work if you like the camera otherwise.

Repair is also an option, but finding a competent repair service is not always easy.

The reason I don’t think it is vignetting is the problem is asymmetric and extends so far into the frame (though If you were applying lens shift it might be vignetting).