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Message |
    
thomas dromer
Tinkerer
Username: Thomas
Post Number: 1
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, July 31, 2006 - 03:29 pm: | 
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Hi,
I have a problem with my Pentax Me Super that I got three months ago. The curtains became quicker so my films stay black (between 1/2000s and 1/125s) or underexposed with low speeds.
The exact same problem has already happend on the Me Super I had before so I guess it could be a common problem.
It is very easy to see that the curtains are going faster beacause, if I open the back, fire and look through the lens, at 1/2000s, there is no light visible. I tried the same thing with one another Me Super I have and I can see a bit of light at that speed.
Has it ever happend to anyone? Do you have any ideas? Is there a post about this already?
Thanks for your help.
(Sorry if my english is not very good.) |
richard a oleson
Tinkerer
Username: Rick_oleson
Post Number: 13
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, July 31, 2006 - 08:11 pm: |
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It sounds like your problem is not that the curtains are moving too fast, but that the second curtain moves faster than the first curtain. This is probably caused by the first curtain hesitating, rather than by the second curtain speeding up. Hesitation of a curtain is usually caused by dirt, either in the bearings of the curtain spindle or in the mesh of gears that are connected to the curtain spindle.
Mechanical Pentaxes are designed for easy access to the curtain spindles, but I have not worked on the electronic ones and I have a feeling that they are not quite so easy to open up. |
Don Coppola
Tinkerer
Username: Don
Post Number: 3
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, August 01, 2006 - 07:23 am: |
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You can check the mech. condition of the shutter by removing the batteries & lens & firing the camera @ auto or M @ a constant lite source. You should see the the full aperture -(dimly) if the shutter is ok. If the timing sw. in the shutter block makes poor contact - w/batteries, then you can get the symptons you've described. A faulty shutter magnet can cause the same problem. If the over led is on, & you get a fast speed @ auto, suspect the asa resistor. I had this happen years ago in summer humidity & it caused underexposure. You could try self cleaning the asa & dia. resistors by turning them from min to max positions a good # of times. This was a help back then but I eventually removed the cover to clean them w/lighter fluid. |
Helen
Tinkerer
Username: Helens
Post Number: 2
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, August 03, 2006 - 07:37 am: |
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Don,
It was useful and reassuring to me that you mentioned that. I've noticed that the ME Super and its close relatives (I have an ME F too) do seem very susceptible to the ASA dial contamination problem. I received my ME Super recently, in lovely condition, but showing the "disco light" syndrome (mad flickering of loads of LEDs, and way-too-high metered shutter speeds which were then delivered on Auto. I eventually found out that it was the problem you mentioned - and that turning the ASA dial with gusto to and fro a number of times, fixed it. Sometimes the mode dial around the shutter release seems to benefit from this too, as it can somehow contribute to the problem. The ME F was the same. It's been incredibly (and unusually) humid in the UK over July, and this caused the problem to reappear in a milder form, but it seemed to go away with this treatment. I may eventually take the cover off and do as you did!
Helen |
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