Originally posted by ydenk Can aperture cleaning resolve this problem? I would like to use a local repair shop and they have suggested cleaning is a common fix, but solenoid parts replacement might be problematic.
If they really recommended to clean the aperture, then this would be nonsense.
The aperture is inside the lens. I had once read a similar claim by one of the official repairshops in Germany.
They said that sticky apertureblades or sticky mechanism on old M lenses would cause ABF.
This of course cannot be:
The standard position of that part which moves the aperture-mechanism (at the K-bajonet left bottom) is downwards:
The springs are under tension, ready to release.
The same for the plunger of the solenoid, it is held by he magnetic force, the spring to bring it back into position is as well
in tension. Ready to release.
So actuation the solenoid actually is a release of tension.
If the solenoid does not actuate, ONLY because the plunger is stuck.
If you want to know more study:
Manual: Solenoid replacement: Pentax K-S2 (and K-70) - PentaxForums.com
plus:
A LITTLE BIT OF HISTORY: Development of the solenoid in Pentax cameras - PentaxForums.com
and if this was really the message that local repair shop gave you then better avoid it. But invite them to read those links.