Tom, thanks for the information, suggestions, ...and empathy! I reluctantly removed the lenses from the shutter last night and tore into it for a follow-up inspection. One thing I saw was that the high speed spring and cam appear to be doing just what they are supposed to - contact is made just above the 200 mark on the cam ring thingy (only at 400 does the boost kick in), and the spring is being wound normally when this occurs without binding or anything like that. Also, checking the numbers above, the duration at 400 is in fact half of what it is at 200, so that is consistent. Without the high speed mechanism engaging, the speed would have been the same and the error at the highest speed would have continued its trajectory to an even higher value, instead of leveling off. So all in all, I think that part of the shutter is actually OK!
But I discovered a curious thing last night that I hadn't noticed before. At one of the shutter blade locations, there are actually two blades, so it basically appears as if that blade were doubled. There are a total of 6 blades instead of 5, and at the double blade location the adjacent blade actually slides between these two. Is that normal for this shutter? If not (perhaps an assembly error at the factory?) it might explain the slowing of speeds on the high end. Does anyone know? I can take a picture of this later if it helps to explain what I am seeing.
Last edited by Denverdad; 06-11-2014 at 12:16 PM. Click to view previous post history.