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04-29-2014, 08:13 PM   #31
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QuoteOriginally posted by Austin Smock Quote
I'm using a kr-10
Oops, sorry, forget about what I said... probably need to focus on whether the kr-10 is working properly.

04-30-2014, 12:26 AM   #32
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QuoteOriginally posted by Austin Smock Quote
Ok so when the lens is on the camera the aperture won't hold, like when I move the ring to a higher f stop it slings back to a lower f stop and vice Versa, any ideas why it's doing this?
I don't understand what you mean by it "slings back". The camera and lens should work in an "auto aperture" mode meaning that it remains wide open except when the shutter is open. Releasing the shutter will flip the mirror up, close down the iris to the f-stop selected and open and close the shutter. After the shutter closes the mirror flips down and the iris goes back to wide open. If the camera has a depth of field preview button/lever you can close down the iris that way.

To check if the lens stops down when the shutter is released set a low shutter speed or "B" (remains open until shutter is released) and look through the front of the lens as you release the shutter.

A copy of the user manual can be found here:
ricoh kr-10 users manual, sears KSX
04-30-2014, 07:40 AM   #33
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QuoteOriginally posted by Not a Number Quote
I don't understand what you mean by it "slings back". The camera and lens should work in an "auto aperture" mode meaning that it remains wide open except when the shutter is open. Releasing the shutter will flip the mirror up, close down the iris to the f-stop selected and open and close the shutter. After the shutter closes the mirror flips down and the iris goes back to wide open. If the camera has a depth of field preview button/lever you can close down the iris that way.

To check if the lens stops down when the shutter is released set a low shutter speed or "B" (remains open until shutter is released) and look through the front of the lens as you release the shutter.

A copy of the user manual can be found here:
ricoh kr-10 users manual, sears KSX
The f-stop won't stay unless I hold the aperture ring
04-30-2014, 10:21 AM   #34
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QuoteOriginally posted by Austin Smock Quote
The f-stop won't stay unless I hold the aperture ring
The aperture ring shouldn't move unless you change the setting. When you took it apart you may not have put it back together right. There are two levers that work the aperture. A long one which protrudes from the mount and a shorter one that fits into a C shaped guide on the inside of the aperture ring and rides along the long slit in the mount when the aperture setting is changed...Two things the lever has to be in the C shaped guide and when it is put back together the marks on the aperture ring and lens casing have to align correctly..

04-30-2014, 06:45 PM   #35
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QuoteOriginally posted by Austin Smock Quote
The f-stop won't stay unless I hold the aperture ring
You probably lost the ball bearing and/or spring that clicks into the detents on aperture ring. Does it click and stop when you turn the ring or does the ring turn freely? If the later you lost the ball bearing.
04-30-2014, 06:59 PM   #36
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QuoteOriginally posted by Not a Number Quote
You probably lost the ball bearing and/or spring that clicks into the detents on aperture ring. Does it click and stop when you turn the ring or does the ring turn freely? If the later you lost the ball bearing.
The ring turns freely
04-30-2014, 07:09 PM   #37
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QuoteOriginally posted by Not a Number Quote
You probably lost the ball bearing and/or spring that clicks into the detents on aperture ring. Does it click and stop when you turn the ring or does the ring turn freely? If the later you lost the ball bearing.
Good Catch! I forgot about that.
04-30-2014, 07:27 PM   #38
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Even without the detent ball it should stay put, so it may not be put back together properly yet.

04-30-2014, 07:42 PM   #39
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QuoteOriginally posted by Not a Number Quote
Even without the detent ball it should stay put, so it may not be put back together properly yet.
Do you have any idea what I might not have done properly?
05-01-2014, 08:30 AM   #40
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The ball bearing can be replaced if you know what size it is - normally from 1-2mm. You might have to buy a 50-100 of them though. Try eBay or Micro Tools. The spring might be more difficult to replace but it still may be there.

The linkages may not be connected correctly. You'd have to either be familiar with the lens, can find an example or be mechanically inclined and can figure it out by trial and error.

Replacing the ball may just solve the problem.
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