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06-25-2019, 08:32 AM   #16
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QuoteOriginally posted by UncleVanya Quote
I disagree - but again I don't know this for certain. I just recall reading that the solenoid for aperture and something else shutter related is tied together in the low end shutter/aperture block and handled with separate solenoids in the high end systems like a K-3. I will try to dig that up but it's a needle in a haystack issue. I have been unable to find this and hope that someone else recalls where it is documented.
The K7/5/3/K01/KP and K1 don't use a solenoid at all. They use a sophisticated motor. (larger, more expensive)

QuoteOriginally posted by UncleVanya Quote
To be clearer, what I recall (but can't find) was that eventually untreated the solenoid stops operating the shutter but since others are using their bodies for a long time... Perhaps I'm misremembering.
The solenoid is part of the aperture mechanism. The shutter and its mechanism are run also by 2 powerfull but very different solenoids. Of course all is linked

if one has an A-lens in use, but if one uses manual lenses in M-Mode, the solenoid is not used at all.

Applying series shots to losen up the stuck plunger of the solenoid can do further damage to the aperture-control-mechanism as at times does a filed/sanded solenoid but it does no damage to the shutterbox / shuttermechanism.

So usually a K-30 or any other body with a defunct solenoid will work fine in M-Mode.

06-25-2019, 12:23 PM   #17
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QuoteOriginally posted by UncleVanya Quote
To be clearer, what I recall (but can't find) was that eventually untreated the solenoid stops operating the shutter but since others are using their bodies for a long time... Perhaps I'm misremembering.
The problem here is that all kinds of people claim all kinds of things about the K-30/50/S2/70; they don't do a very good job of documenting what they did, nor do they do a very good job of observing results. As a K-30 owner for four years now, I have been carefully observing - and asking question - for about three years now. I am quite certain that there are few - if any - documented cases of shutter failure on the K-30/50/S2/70 line other than the people who used a burst to "free up" a failing aperture control. There are other parts which are less robust.
06-26-2019, 01:10 PM   #18
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QuoteOriginally posted by reh321 Quote
The problem here is that all kinds of people claim all kinds of things about the K-30/50/S2/70; they don't do a very good job of documenting what they did, nor do they do a very good job of observing results. As a K-30 owner for four years now, I have been carefully observing - and asking question - for about three years now. I am quite certain that there are few - if any - documented cases of shutter failure on the K-30/50/S2/70 line other than the people who used a burst to "free up" a failing aperture control. There are other parts which are less robust.
That is interesting information. I would have to dig back and look but I know there were a few - but those may stick out in my mind and skew my thinking. Thanks.
06-26-2019, 11:39 PM   #19
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QuoteOriginally posted by UncleVanya Quote
That is interesting information. I would have to dig back and look but I know there were a few - but those may stick out in my mind and skew my thinking. Thanks.
There were a few, just search "Pentax K30 + shutter problem + pentaxforums" and you find them.

In some cases it turned out to be misunderstood, i.e. mistaken for the aperture problem, in other cases mishandling the shutter during cleaning, broke cables;
one case turned out to be a damaged motor for lifting the mirror up. Latter can happen when one grinds/sands the green solenoid or applies too often series shots to losen a stuck solenoid, because in both cases the very precise interlinked mechanism is getting messed up. The motor sits on the diaphragm control unit and of course is interlinked with the whole mechanism.


some of those mixups:
Aperture Block / Shutter Failure - PentaxForums.com
Pentax K-50 /K-30 Stuck Shutter - PentaxForums.com

07-24-2019, 12:27 PM - 1 Like   #20
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I'm now resigned to using lenses with aperture rings on my afflicted K-50. One thing though - for faster shooting, you can operate in Av mode - as long as you compensate for the set aperture. So, you select an aperture (maybe on the basis of best sharpness), and then set appropriate exposure compensation. For example, for an f2 lens set to f4, you need to set +2 stops exposure compensation.

Works a treat - and exposure is probably a lot more accurate than using M mode and stop-down metering.

(By the way, it's been a long time since I was last here - so hello again everyone!)
07-24-2019, 12:44 PM   #21
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QuoteOriginally posted by m42man Quote
I'm now resigned to using lenses with aperture rings on my afflicted K-50. One thing though - for faster shooting, you can operate in Av mode - as long as you compensate for the set aperture. So, you select an aperture (maybe on the basis of best sharpness), and then set appropriate exposure compensation. For example, for an f2 lens set to f4, you need to set +2 stops exposure compensation.

Works a treat - and exposure is probably a lot more accurate than using M mode and stop-down metering.
Once you've done the arithmetic, count on your fingers or whatever, to figure out EC, I'm surprised you'd find it faster.
07-24-2019, 10:41 PM   #22
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QuoteOriginally posted by reh321 Quote
Once you've done the arithmetic, count on your fingers or whatever, to figure out EC, I'm surprised you'd find it faster.
Obviously not particularly viable if you want to change aperture a lot, but very often I find I set an aperture for a set of shots - and the exposure accuracy is an attractive feature...
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