Vivitar Series One 90-180/4.5 Flat Field Macro and Pentax K10D

I received my new Pentax K10D today. The main reason I got it is because I
have some excellent manual focus lenses that I wanted to use on it. One of
those is a Vivitar Series One 90-180/4.5 K-mount lens--an extraordinary
lens. Unfortunately, there is a metal collar that partially surrounds the
rear element that prevents the lens from mounting on the camera. The other
K-mount lenses I have mount without difficulty. Has anyone had any
experience with this problem. If I could get the collar off the lens and
could grind it down, I believe the lens would fit but I am not sure how to
do this (it would be too risky to try to do this with collar mounted because
it is so close to the rear element. Any help would be appreciated. Thanks.

David Goldstein wrote:

I received my new Pentax K10D today. The main reason I got it is because I
have some excellent manual focus lenses that I wanted to use on it. One of
those is a Vivitar Series One 90-180/4.5 K-mount lens--an extraordinary
lens. Unfortunately, there is a metal collar that partially surrounds the
rear element that prevents the lens from mounting on the camera. The other
K-mount lenses I have mount without difficulty. Has anyone had any
experience with this problem. If I could get the collar off the lens and
could grind it down, I believe the lens would fit but I am not sure how to
do this (it would be too risky to try to do this with collar mounted because
it is so close to the rear element. Any help would be appreciated. Thanks.

Are you sure it's a K-mount lens? Vivitar made lenses in other mounts
that look like K-mounts, such as Yashica/Contax.

It is definitely a K-mount lens. I have used it for years on a Pentax K
mount film body.
"Paul Mitchum" wrote in message
...
David Goldstein wrote:

I received my new Pentax K10D today. The main reason I got it is because
I
have some excellent manual focus lenses that I wanted to use on it. One
of
those is a Vivitar Series One 90-180/4.5 K-mount lens--an extraordinary
lens. Unfortunately, there is a metal collar that partially surrounds
the
rear element that prevents the lens from mounting on the camera. The
other
K-mount lenses I have mount without difficulty. Has anyone had any
experience with this problem. If I could get the collar off the lens and
could grind it down, I believe the lens would fit but I am not sure how
to
do this (it would be too risky to try to do this with collar mounted
because
it is so close to the rear element. Any help would be appreciated.
Thanks.

Are you sure it's a K-mount lens? Vivitar made lenses in other mounts
that look like K-mounts, such as Yashica/Contax.