03-22-2011, 02:09 PM
[quote name='RussellB' timestamp='1300765802' post='7005']
Here's a $140 (yikes) M42 focusing helicoid for the Nex.
http://cgi.ebay.com/21MM-FOCUS-STROKE-HE...1161wt_957
But this thing, and also buy a M42-to-Leica-39 stepdown ring for about $4, and you can probably focus any-Leica-thread-lens-over-44mm-focal-length on a Nex. A $6 dollar set of Gissin M42 extension tubes, 3 pieces totalling 49mm length, from Ebay, might also be relevant to the project.
The minimum length of this 21mm long focuser on the Nex brings you to about 18+21=39mm from the sensor plane, don't know if that's the flange-to-film distance you need or not.
This is not to say that you should mount the lens on a Nex. Am simply documenting the economics of doing so.
[/quote]
Thanks for the very interesting idea of the focusing helicoid. There are also focusing helicoids of different lengths for M42, which then could be combined with M42 to EF-mount and M42 to for instance NEX or NX mount... I will have to study what the different flange/film distances will mean for the lens application. If there would be a Panasonic GF with the GH1 sensor it might also be interesting.. not a fan of the 4x3 image format.
Here's a $140 (yikes) M42 focusing helicoid for the Nex.
http://cgi.ebay.com/21MM-FOCUS-STROKE-HE...1161wt_957
But this thing, and also buy a M42-to-Leica-39 stepdown ring for about $4, and you can probably focus any-Leica-thread-lens-over-44mm-focal-length on a Nex. A $6 dollar set of Gissin M42 extension tubes, 3 pieces totalling 49mm length, from Ebay, might also be relevant to the project.
The minimum length of this 21mm long focuser on the Nex brings you to about 18+21=39mm from the sensor plane, don't know if that's the flange-to-film distance you need or not.
This is not to say that you should mount the lens on a Nex. Am simply documenting the economics of doing so.
[/quote]
Thanks for the very interesting idea of the focusing helicoid. There are also focusing helicoids of different lengths for M42, which then could be combined with M42 to EF-mount and M42 to for instance NEX or NX mount... I will have to study what the different flange/film distances will mean for the lens application. If there would be a Panasonic GF with the GH1 sensor it might also be interesting.. not a fan of the 4x3 image format.