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Forum: Pentax K-30 & K-50
02-08-2021, 02:37 PM
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The shutter is driven by two very strong solenoids.
The mirror is lifted by a motor which sits on the diaphragm-control-unit (but is not directly connected)
Usually 1 motor and a socalled "return-spring" but sometimes by a return-motor.
How this works with the return-spring is shown here:
You Tube
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src="https://www.youtube.com/embed/kLU5oygrkpw?controls=1" allowfullscreen>
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ohh... gosh... it's a Canon:fedup:
The complex mechanism behind the diaphragm-control-unit is well shown here with this analog MZ5n:
https://www.pentaxforums.com/forums/attachments/8-pentax-film-slr-discussion...al-mz5-002.jpg |
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Forum: Pentax K-30 & K-50
01-28-2021, 08:12 AM
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- mirror is operating ( view finder works), except it does not go up when "sensor cleaning" enabled
Does the mirror goes up in live View mode even the shutter remains closed?
Does the mirror goes up and down when shooting in ordidary manner (using optical view finder)?
- shutter stuck, completly closed
You can check if the shutter is stucked on first curtain or second curtain. Just elevate gently the mirror with your finger and look for metallic dot in upper left corner. It is almost hiding but can be seen. If you see that "dot", the shutter is in normal position (prepared to fire, as always after taking picture), stucked on first curtain. If you see the metallic dot in lower left corner, the shutter is stucked on second curtain (it means the shutter opened first curtain and closed the second, but did not completed whole cycle to be prepared for the next shot). This can be the sign of shutter failure, but not mechanical in origin, most likely electronical. If the previous owner did something wrong on the mother board, shortened the circuitry, the shutter can not operate properly.
- the flash does not fire, even in forced mode
Maybe this can be related to the fact that shutter curtains do not operate properly. This can also indicate capacitor problems. You can check if the capacitor is charging, but I don't know if it's ethical to offer to try it with your fingers, because the discharge is really unpleasant (I've experienced this more than once) :)
- aperture wheels locked, to move it I have to apply much more force (feel that some spring is blocking it, it returns to its previous place after removing the pressure)
What diaphragm wheels are you talking about? Do you mean the controller of lens' aperture lever that is located on the left side (looking from the mount side)? You can push it up by finger with some force and normally it returns back due to force of the spring inside (it is visible through the slit). That is normal behavior. The normal position of the controller is in the middle. For the controller of aperture lever to stuck mechanically there should be damage of gears inside the mirror movement mechanics. I opened once that "pandora box". OMG!! Luckily I assembled it back correctly.
BTW, if you meant wheels that are partly visible from the side of solenoid ant you tried to spin them applying the force, it is normal to return for them after removing force, because there are some springs inside as well as a claw, similar to an engine crankshaft.
- solenoid is not moving at all, position of its levar is not affecting the wheels ( it schould be locking when it is down, after applayng the current)
You can remove that solenoid by unscrewing 1 screw and move the lever operated by the solenoid core with your finger. BTW, I noted that in Pentax cameras the manufacturer use connecting wires of the same color even in different models. Check if one is lightly rose and another lightly violet (should be for sure). Are those wires soldered in correct way as in picture below?
 20201119_210250 by MG Mindaugas, on Flickr
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Forum: Pentax K-30 & K-50
01-28-2021, 10:36 AM
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Yes, looks like shutter is stucked on second curtain.
When I had this same problem with my K-1, the problem was failure of shutter charge motor. But K-30 does not have this part.
I think some problems occurred in circuitry when the camera was disassembled and maybe not properly managed during "repair" of solenoid.
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Forum: Pentax K-30 & K-50
01-28-2021, 06:43 AM
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Almost certainly
That means that the mirror-up mechanism was jammed and it got released.
Good, but to bad:
These are interrelated. The shutter is opened and closed with 2 other solenoids, both sitting deep inside the camera,
you'll need to take everything apart to get to it:
But then, if the shuttersolenoids are damaged you can forget it, I have never seen them on offer anywhere.
That was to be expected with all the wheels being jammed.
Possibly that some of the "return-springs" of some wheels jumped out, again, almost impossible to repair.
Sure, the solenoid does not move and the shutter won't open.
Well, of course you can try to dig deeper.
I see it like this:
parts that can be used for spares:
- focusing screen (fits K5/3/KP, K30/50/500/K-S1/2/70)
- LCD fits many
- Back cover
- Top-cover
- the battery hook!
- motherboards
- sensor
Some ebay-sellers make more money with parts than a defunct complete body.
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Forum: Pentax K-30 & K-50
01-27-2021, 11:40 AM
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Hi,
I've found this thread about mirror problems on K-50 (which is a twin of K-30) : Mirror stuck problem in new Pentax K-50 - PentaxForums.com
To sum up this thread:
- Mirror misbehave or stuck could indeed happen on K-50
- Could be related to battery - using AA adapter solved the problem for some people
- Could be related to diaphragm block (someone mentioned Ricoh replaced the diaphragm block under warranty to fix mirror up problem)
- Could be related to DA-L lenses with plastic mount - people mentioned using metal mount lens to fix mirror issue
Since the solenoid might have been sanded, I'm afraid your K-30 may be toasted :(
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Forum: Pentax K-30 & K-50
01-27-2021, 10:42 PM
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just to be sure, chech the wires and colors, as well as soldering quality.
I have problems with K-x, something similar speaking about mirror failure, shutter does not fire as well, but this behavior accured after some experimental changes in sensor, changes that did not include any soldering on the sensor plate. Camera makes just 1 mirror action, shutter does not fire at all and then camera freezes with shake reduction always in action. But removing the battery solves this problem until next picture :)
I replaced whole sensor block with donor one and camera worked OK until I made same experiment with sensor.
As I know K-x has some problem with circuitry or power management, so these problems could be not related to K-30.
Here is K-30's mother plate. Before unsoldering.
 20160924_145225 by MG Mindaugas, on Flickr
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Forum: Pentax K-30 & K-50
01-27-2021, 12:49 PM
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I am certain you are right.
But then there is a slight but important difference between those screws which screw into metal and those which screw into plastic.
Some have a slight difference in thickness, thread, lead and pitch.
That's why I take either photos of each side of the body or make a short drawing, pinch tiny holes into the places the screws are located
and stick them in there.
A simple drawing is done within few minutes.
But because I knew this was not going to be just one repair anymore, photos glued on cardboard served best.
One can actually just copy photos from the internet and print those.
So what all screws have in common:
They are all JIS!
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Forum: Pentax K-30 & K-50
01-27-2021, 09:28 AM
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Here are photos of a K30 and all screws with their individual length:
Bottom:
Top:
Sides + underneath rubber eyepiece:
K50 and K500 have one screw less in the center underneath the pop-up-flash!
Otherwise identical.
Thanks to a person in Saarbrücken, Germany who sent me the photos!
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Forum: Pentax K-30 & K-50
01-26-2021, 02:33 PM
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For the heck of it go to the menu and select sensor cleaning, mirror up, and maybe you can see if anything moves. Just another way to actuate the mirror.
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Forum: Pentax K-30 & K-50
01-27-2021, 06:01 AM
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Yes I know it's up, that just to see if you can see any action at the mirror. When you "run the cleaning" I'm guessing you are talking about dust removal which shakes the sensor and does make a buzzing noise. The mirror up for sensor cleaning is for manual cleaning and simply locks the mirror up. I thought engaging that may help complete a cycle. Once you do that the mirror normally drops back down when you turn the camera off. I don't know for sure, but I think the bad solenoid could definitely be causing that.
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Forum: Pentax K-30 & K-50
01-27-2021, 09:30 AM
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