Are these images symptomatic of shutter failure?

Question

This is a burst sequence taken with a Canon 1D Mark II N in high-speed mode (8fps). You can see the bright line down the center and the dark area in the upper-right. I have several other sequences with similar artifacts.

Is my shutter failing, or is there something else going on?

Shutter count utilities at http://www.foxbat.me.uk/2.0/index.php#/1dcount and http://www.camerashuttercount.com/ both indicate a shutter count of ~79,000, though I do not know the accuracy of these sites, nor do I have an estimate of the camera's shutter count as I got the camera used with no pedigree. My understanding is that this particular model's shutter life expectancy is around 200,000 actuations and I've heard of people getting over 400,000.

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UPDATE: I decided to crack it open and inspect the darn thing:

Seems pretty conclusive that it's the shutter, though if anyone wants to dispute the claim I'm game to entertain it :-) Guess it's off to the shop...

Asked by djangodude

Answer

My guess for the shutter speed in the comment was based ob the approximate width of the bright strip relative to the image width, multiplied by the sync-speed. I assumed a 1/250sec sync speed.

Just a speculation: it looks like the shutter blades get stuck for an brief instance around the middle of the frame. It is possible that you have a piece of dirt stuck there, or that the spring or rails are about to fail. Try to decrease and increase the speed by a stop and see if the stripe gets twice as wide and as narrow. If so, it is indicative that it is indeed the shutter having a problem.

UPDATE after the mystery was resolved - I'd think the first thing to do (OK, maybe the second) would be to remove the lens and have a look at the internals... but that's just me ;-)

Answered by ysap

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