Big problem with KR mount lens

Has anybody got any info on how to remove a KR mount lens from a Pentax *ist DS?

A friend lent me his macro lens which is a KR mount - fitted OK - won't come off it's solid.

Any suggestions?

Thanks Chris

This is a well-known problem - but obviously not well-enough.

Ricoh lenses have a small pin that tends to get caught in the AF actuator of a Pentax auto-focus camera.

There is no easy solution. It might be possible to disassemble the lens from the front, though you usually need to get at it from the rear.

You might be able to drill into the lens and either push the pin out of the way, or drill right through it.

The best bet might be to develop an interest in macro photography, and buy another body for other genres.

Sorry I can't be more helpful. Somebody sold me a "Pentax-mount" Vivitar S1 lens on Ebay. It was actually a Ricoh, but fortunately it didn't lock itself on when I innocently attached it to my D.

G

There's a related thread here:
https://www.pentaxuser.com/forum/viewtopic.php?t=1723

They suggested sliding a piece of paper (or razor) between body and lens to unlock the offending pin.
(
Here are perhaps some of the source threads:
http://forums.dpreview.com/forums/read.asp?forum=1036&message=11483409
http://forums.dpreview.com/forums/read.asp?forum=1036&message=14958356
)

Another thread (for a Tamron lens):
https://www.pentaxuser.com/forum/viewtopic.php?t=2087

Matt

flat metal automotive feeler guages (in conjunction with repeatedly pressing and releasing the lens release on the body)might work if there's any wiggle room to get it in there.
in fact you might try just pressing the lens release on the camera body and allowing it to snap back. the idea is to wiggle the lens back and forth and get it centered so the pin in the lens will hopefully have some slack to move. then snap the button on the body and simultaniously turn the lens.
the idea is to allow the af drive shaft (which moves up and down with the lens lock, to push up on the lens pin.

Thanks for all your help, that certainly seems to be it, can't get the razer blade in at that point, but will perservere.
Many thanks Chris

Just to let you all know that the razer blade trick worked a treat, took half an hour fiddling, but it worked.
Thanks again for the help.
Chris