dhbebb Posted August 31, 2009 Share Posted August 31, 2009 <p>After taking pictures for 50+ years, I was recently taken by the EOS system, among other things as a means of using not only Canon lenses but also Leica R and Nikon F lenses via adapters. These work great, provided I accept stop-down metering. I then bought a couple of adapters for Pentax K mount (no electrical or mechanical contacts, just solid metal) and found that the camera mirror jams with a lens and adapter in place, and the battery indicator shows exhausted. Changing the battery does not help, removing the lens does (makes no difference whether the adapter itself is on the camera, except that you have to take the lens plus adapter off the camera to separate them).<br> The reason for this would seem to be that Pentax K lenses have a flat pin projecting rearwards which closes down the automatic diaphragm to take a picture. There is also a small guard plate of thicker metal right next to the pin, presumably to protect it from damage when the lens is off the camera.<br> Since these features are present on all Pentax K lenses, it would appear that a Pentax K lens to Canon EOS body adapter cannot possibly work. Has anyone found an adapter that does work, or have the Chinese adapter makers simply goofed?</p> Link to comment Share on other sites More sharing options...
jcolwell Posted August 31, 2009 Share Posted August 31, 2009 <p>A Pentax K lens can work with a simple mechanical adapter on an EOS 1.6x crop factor (CF) body with no modifications, but you have to remove the aperture control lever and lever shield to use it on a 1.3x CF or full frame (FF) body. I frequently use Pentax K lenses (most often SMC Pentax 18/3.5 and SMC Pentax-A 50/1.4) on all three EOS sensor sizes (1.6x, 1.3x & FF). In my experience, performing the aperture leverectomy has no significant effect on resale value, and it doesn't "disable" the lens for use on Pentax bodies, it simply makes it into a manual aperture lens, same as on EOS. Here's a few links with general and Pentax-specific information.<br> <p>Bob Atkins <a href="http://www.bobatkins.com/photography/eosfaq/manual_focus_EOS.html">http://www.bobatkins.com/photography/eosfaq/manual_focus_EOS.html</a><br />NK Guy <a href="http://photonotes.org/articles/eos-manual-lenses">http://photonotes.org/articles/eos-manual-lenses</a><br />Markerink mounts and registers <a href="http://www.a1.nl/phomepag/markerink/mounts.htm">http://www.a1.nl/phomepag/markerink/mounts.htm</a><br />Oleson's lens mounts <a href="http://members.tripod.com/rick_oleson/index-99.html">http://members.tripod.com/rick_oleson/index-99.html</a><br> <p>Pentax to EOS alt lens questions.. <a href="http://www.fredmiranda.com/forum/topic/718836">http://www.fredmiranda.com/forum/topic/718836</a><br />Altering Pentax K Mount to Canon Eos 5D <a href="http://www.fredmiranda.com/forum/topic2/574010">http://www.fredmiranda.com/forum/topic2/574010</a><br />M42 telephoto <a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00J01o&tag">http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00J01o&tag</a>=<br />Pentax K and M42 <a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00ExzY">http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00ExzY</a></p> </p> </p> Link to comment Share on other sites More sharing options...
Robert DeCandido PhD Posted August 31, 2009 Share Posted August 31, 2009 <p>HappyPageHK - His name is Rudolph in Hong Kong and he can be found on the Big Auction site. His adapters are about $75 each.</p> <p>If you go over to FM Forums (Fred Miranda Forums) in the alternative gear section, they often discuss adapters for lenses (Pentax, Minolta, Nikon, Leica, Mamiya) to Canon bodies.</p> <p>I have the HappyPageHK adapters and they work fine. He is very responsive to emails...highly recommended.</p> <p>rdc/nyc</p> Link to comment Share on other sites More sharing options...
Robert DeCandido PhD Posted September 1, 2009 Share Posted September 1, 2009 <p>For a Nikon lens to Canon body adapter of the new Nikon "G" style lenses, see this article:</p> <p><a href="http://www.davidclapp.co.uk/blog/articles/5-g-volution-nikon-g-canon-eos-adapter.html" target="_blank">http://www.davidclapp.co.uk/blog/articles/5-g-volution-nikon-g-canon-eos-adapter.html</a> </p> Link to comment Share on other sites More sharing options...
dhbebb Posted September 3, 2009 Author Share Posted September 3, 2009 <p>Thanks for responses - HappyPageHK seems not to have Pentax adapters at present. The cheap adapters I have at present place the lens focus/aperture witness mark at about 30 degrees past top dead center, this could be the reason why the lens is fouling. I am going to try a different brand of Pentax adapter</p> Link to comment Share on other sites More sharing options...
artworks Posted December 9, 2009 Share Posted December 9, 2009 <p>Ayone find an adapter that registers top dead center? I have the 28mm shift lens and chinese adapter and the misregistration will not allow parallel and perpendicular shifts. All the ebay ones appear the same when looking close at photo including Photdoix where I purchased mine<br> Thanks</p> Link to comment Share on other sites More sharing options...
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