Author |
Message |
ism
Rating: N/A Votes: 0 (Vote!) | Posted on Tuesday, September 13, 2005 - 12:44 pm: |
|
Shutter problem resulting in only 20% to 40% of left side of frame being exposed at high shutter speed. Sticky shutter? How easy is it to lubricate? Also some frames have a trapezoidal shaped whitish area covering around 80% of the central area of the frame. I suspect the frames affected could be before/after lens changes. Could this be a light leak and the trapezoidal shape due to the mirror? Your assistance would be much appreciated. |
rick
Rating: N/A Votes: 0 (Vote!) | Posted on Tuesday, September 13, 2005 - 08:31 pm: |
|
The shutter is fading, or tapering or whatever your preferred term is: the second curtain is traveling faster than the first. Before trying to fix it by increasing tension on the first curtain spring, you should clean the bearings of the shutter curtain spindles. This is fairly easy in Pentaxes, because the front panel comes off for access. See http://rick_oleson.tripod.com/index-113.html for a sketch of how to get there. I assume the "whitish" area is on the negative, not the print, right? In this case it probably means the mirror is in the way..... although, this seems odd: if the mirror is hung up in its travel, the shutter should not open until it has gone all the way up. So a slow mirror should mean a slow shutter release, not an obstructed view during exposure. I can't think of anything else, though, that could cause such an effect. |
ism
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, September 14, 2005 - 01:46 am: |
|
Thanks Rick. The whitish area is on the print- shows as dark area on negative. |
rick
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, September 14, 2005 - 04:23 pm: |
|
this would mean that you are getting unwanted light on the film, as opposed to a shadow such as would be cast by the mirror being in the way. such an effect in a trapezoidal shape is outside my experience ... or at least nothing comes to mind. If it came in conjunction with changing lenses, it could be related to light getting around the shutter curtains, either at top and bottom or at the overlap between the 2 curtains. I think your camera needs general CLA attention, and perhaps the solution to this mystery will become apparent in the course of the service. |
|