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I am unaware of a common fault for the ME Super where the mirror rises on wind, but only with a lens mounted to other than the maximum aperture, though I can imagine there might be an issue with the lens, specifically the aperture actuator lever. With the lens off the camera...
- Examine the lens aperture actuator lever thoroughly. Does it appear bent or out of alignment? Is there evidence of heavy wear?
- While looking through the rear of the lens, operate the aperture ring from widest to narrowest settings. Movement should be regular and distinct, without hesitation.
- With the aperture ring at its narrowest setting, flick the actuator lever with your fingertip. The aperture action should be quick, smooth, and complete, with no hesitation or roughness. Confirm for all stops on the aperture ring.
- Confirm that the aperture blades are free of oil or grease contamination. They should appear clean and dry without indication of scratches or wear.
If any of the above are a problem, the issue may well be with your lens, particularly if the aperture actuator is jammed or stiff or does not easily deflect to the full-open position. If the lens appears good and this problem occurs with lenses other than this particular 50mm, there might be damage to or lack of lubrication in the actuator mechanism on the body. Either may result in the exposure or wind sequence not proceeding normally.
In regards to the trailing curtain being hesitant...This may or may not be related to the issue above, but is indication that the camera might benefit from a service call. A routine CLA (
Clean,
Lubricate,
Adjust) often is all that is needed to address these types of issues. Initial evaluation during a CLA will usually determine whether extensive repair is needed.
I did not address whether either is appropriate for self-repair. For electronic cameras such as your ME Super, most of use do not have the tools, specialized lubricants, or training to properly diagnose and put the camera in proper order. There is also a rule of thumb that problems associated with shutter or mirror function should probably be considered "fatal" in that the mirror and shutter of this class of camera is generally not repairable. Of course, it requires a competent repair person to make that assessment.
FWIW, I have a Ricoh XR7 on my shelf downstairs whose aperture actuator mechanism was badly damaged by a defective lens. I keep it for reference purposes and possible source of parts.
Steve