CONTAX CLUB Carl Zeiss 討論區

[Choyin]

thanks for your answer. If the C/Y lenses can be tightly screwed in, I wouldn't damage any part of the discontinued lenses neither.javascript:emoticon''

Can't wait to see you photos of "operation".

[fuwen]

Me too very excited about it. Hope it is easy.
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CONTAX RTS III, Aria - Rolleiflex 3003, SL2000F - Rollei 35RF / Voigtlander R4M - Rolleiflex SL66 / SL66E
Carl Zeiss C/Y T* - QBM HFT - M HFT, ZM T*
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[Raimondi]

ryhl, can't wait to see your modification photos too.

would u consider this PK->C/Y mount modification as a part-time business? i will be your next customer after octopus then. count me in.


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[章魚]

ryhl .. 請有空 post 些 K100 + C/Y 的作品。我很想看看。現在 K100 幾銀 ?
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~ 八 足 怪 ~

[ryhl]

Sorry to have kept brothers waiting. Here is a walkthrough of the works for the modification of the K mount. I shall use Chinese on those parts which are more complicated (as my penpower at home is very unstable and slow, so cannot use Chinese for all of the contents) -

First, a comparison of the K mount before and after the modification-



You can see the small portions of the mount to be removed which are marked in blue -

[jason.lau]

[ryhl]

Forgotten to mention. Only the 3 areas marked in blue in the second picture in the previous message need to be removed. The whole inner ring of the mount which appeared to have been altered is due to minor adjustment works which may not be needed for individual camera. I shall provide more detailed explanations later on.

The 2 pictures below indicate why the areas marked in blue need to be removed.

1. A C/Y lens can be placed in a K mount without any modification. But the blue areas which is of the same thickness as the C/Y mount blades obstruct the lens to be screwed in the body mount -


2. With the removal of the areas marked in blue, the C/Y lens can now be screwed in the K body mount

[vincenthoy28]

just want to know...after modification, can original Pentax K mount lens still able to fix to that camera?
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Damn, my Calon Segur heart fall in love with Haut Brion

[jason.lau]

I start to regret I sold all my C/Y.........

[ryhl]

With the removal of the areas marked in blue, basically C/Y lenses are now able to screw in the K mount. However, Pentax cameras have another feature which obstruct the screw-in of the C/Y lenses - the 限位裝置(for the M42 adaptor ring) on the thin metal piece that is used to grip lenses tightly to the body.

Position of the thin metal piece in the K100D body -


The exact position of the 限位裝置 on the metal piece (circled in the picture). The one on the right is the original 限位裝置. We have to remove it which now appears as the one on the left -



With the removal of this 限位裝置, now our C/Y lenses can be screwed in perfectly into the K mount

[ryhl]

[ryhl]

With the above modifications, basically the Pentax cameras are ready for C/Y lenses. However, for my K100D, I have encountered another problem which I do not notice at the first instance - that is, the exact register of my K100D is slightly longer than that of my C/Y lenses, i.e. it is more than 45.5 mm This rendered my C/Y lenses cannot focus to infinity...

So, have to carry out more modifications one more time -

The first step of this further modification is to sand away a thin layer of the K body mount by sanding paper. I have sanded away about 0.2 mm or so in the process.

The second step is to remove some plastic body material supporting the metal mount ring in the camera body. I used a 筆刀 to pill away a very thin layer of the camera body, as illustrated in the following pic -



After this further modification, the infinity-focus problem is finally rectified.

[ryhl]

Some cautions if any brother would like to try the above modification. Although the exterior appearance of the camera would largely remain the same, there will be some minor scratchs (caused by the pins protruding from the C/Y lenses) inside the camera.

(note : the scratches on the metal mount is not the product of the modification. They are the result of my earlier experimental attempt in converting my mutar I into K mount when I have yet to figure out the above modification method) -





See if my little experience will be of use to brothers who are interested in using C/Y lenses on Pentax DSLRs

[ryhl]

[vincenthoy28]

I have tried this to my ist DL and I would like to advised that there is one small black wire connecting to 限位裝置(for the M42 adaptor ring). Please be careful not to disconnect that or you have to solder it back after disconnect. Else you will lose the AF function...
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事務局長

Damn, my Calon Segur heart fall in love with Haut Brion