do any m42 adapters do auto stopdown?
The m42 lenses stop down by pushing in on the rod. The k-mount stop down by pushing sideways on a lever. I can imagine something where the widget that pushes sideway on a lever, would push on a hinged doo-hickey (pardon the technical engineering jargon) that then pushed on the rod on the lens. Does such an m42 to k-mount adapter exist? On a related note, is what we call m42 the same as what machinists call M42? http://www.besly.com/catl/catl4124ps.htm#M42 -- The fastest way to get your question answered on the net is to post the wrong answer. Larry Colen l...@red4est.comhttp://www.red4est.com/lrc -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: do any m42 adapters do auto stopdown?
On Wed, Apr 1, 2009 at 8:48 PM, Larry Colen wrote: > The m42 lenses stop down by pushing in on the rod. The k-mount stop > down by pushing sideways on a lever. I can imagine something where > the widget that pushes sideway on a lever, would push on a hinged > doo-hickey (pardon the technical engineering jargon) that then pushed > on the rod on the lens. > > Does such an m42 to k-mount adapter exist? No, JCO, there aren't. > On a related note, is what we call m42 the same as what machinists > call M42? > > http://www.besly.com/catl/catl4124ps.htm#M42 Yes, I think so. Leica screw mount is M39. -- Scott Loveless Cigarette-free since December 14th, 2008 http://www.twosixteen.com/fivetoedsloth/ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: do any m42 adapters do auto stopdown?
M42 lenses are 42mm dia. male metric threads with a 1.0 mm thread pitch. (t-mount are similar but have 0.75mm thread pitch) that tool page is for something else very huge and different. JC O'Connell hifis...@gate.net -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Larry Colen Sent: Wednesday, April 01, 2009 8:49 PM To: Pentax-Discuss Mail List Subject: do any m42 adapters do auto stopdown? The m42 lenses stop down by pushing in on the rod. The k-mount stop down by pushing sideways on a lever. I can imagine something where the widget that pushes sideway on a lever, would push on a hinged doo-hickey (pardon the technical engineering jargon) that then pushed on the rod on the lens. Does such an m42 to k-mount adapter exist? On a related note, is what we call m42 the same as what machinists call M42? http://www.besly.com/catl/catl4124ps.htm#M42 -- The fastest way to get your question answered on the net is to post the wrong answer. Larry Colen l...@red4est.com http://www.red4est.com/lrc -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: do any m42 adapters do auto stopdown?
there are no adapters that convert K bodies to acutate m42 auto lens pins. I believe Fuji made a bayonet camera that did have such an adapter,but fuji's bayonet camera was not K mount body. The tool page is NOT same M42 as M42 lenses. JC O'Connell hifis...@gate.net -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Scott Loveless Sent: Wednesday, April 01, 2009 8:58 PM To: Pentax-Discuss Mail List Subject: Re: do any m42 adapters do auto stopdown? On Wed, Apr 1, 2009 at 8:48 PM, Larry Colen wrote: > The m42 lenses stop down by pushing in on the rod. The k-mount stop > down by pushing sideways on a lever. I can imagine something where > the widget that pushes sideway on a lever, would push on a hinged > doo-hickey (pardon the technical engineering jargon) that then pushed > on the rod on the lens. > > Does such an m42 to k-mount adapter exist? No, JCO, there aren't. > On a related note, is what we call m42 the same as what machinists > call M42? > > http://www.besly.com/catl/catl4124ps.htm#M42 Yes, I think so. Leica screw mount is M39. -- Scott Loveless Cigarette-free since December 14th, 2008 http://www.twosixteen.com/fivetoedsloth/ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: do any m42 adapters do auto stopdown?
M42x1 would be the same regardless of whether it is photographic equipment or heavy machinery since it describes a thread with a 42mm diameter and a 1mm pitch. There is no guarantee that something (other than camera equipment) described just as M42 wouldn't be M42 x 0.75 or M42 x 1.25, but I would bet that any M42 lens would be M42x1. Accrording to wikipedia Leica thread mount is M39 x 26tpi (whitworth) which works out at M39x.977. Apparently early Zorki and early Canon RF cameras used M39x1. It gets really murky in the world of large format lenses and shutters where some of the metric sizes are very close to imperial sizes and you need to measure very carefully to work out exactly what you have. Prior to WWII there weren't any real standards and lots of oddball sizes exist. Paul On a related note, is what we call m42 the same as what machinists call M42? http://www.besly.com/catl/catl4124ps.htm#M42 Yes, I think so. Leica screw mount is M39. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: do any m42 adapters do auto stopdown?
The tool page he reference was M42-5 not M42-1 JC O'Connell hifis...@gate.net -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Paul Ewins Sent: Wednesday, April 01, 2009 9:23 PM To: Pentax-Discuss Mail List Subject: Re: do any m42 adapters do auto stopdown? >> M42x1 would be the same regardless of whether it is photographic equipment or heavy machinery since it describes a thread with a 42mm diameter and a 1mm pitch. There is no guarantee that something (other than camera equipment) described just as M42 wouldn't be M42 x 0.75 or M42 x 1.25, but I would bet that any M42 lens would be M42x1. Accrording to wikipedia Leica thread mount is M39 x 26tpi (whitworth) which works out at M39x.977. Apparently early Zorki and early Canon RF cameras used M39x1. It gets really murky in the world of large format lenses and shutters where some of the metric sizes are very close to imperial sizes and you need to measure very carefully to work out exactly what you have. Prior to WWII there weren't any real standards and lots of oddball sizes exist. Paul >> On a related note, is what we call m42 the same as what machinists >> call M42? >> >> http://www.besly.com/catl/catl4124ps.htm#M42 > > Yes, I think so. Leica screw mount is M39. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: do any m42 adapters do auto stopdown?
Yep, that has to be different. I did remember a couple of cases of a "different" M42 in the photo world - an early Adaptall type mount that is M42 x .75 and also a Schneider Componon enlarging lens that used an M42 x .75 retaining ring. Earlier and later versions of the same lens were different sizes (M39 and M50) which caused me much confusion. The Adaptall thread was the one that connected the various lens mounts to the lens rather than the lens to the camera. Paul The tool page he reference was M42-5 not M42-1 JC O'Connell hifis...@gate.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: do any m42 adapters do auto stopdown?
Tamron adaptall(1)was not a thread lens mounting system, it was very similar to adaptall2 actually which is sort of a breech/bayonet system. The M42x0.75 mm threaded universal lens mounting system was/is called T-Mount, not adaptall. JC O'Connell hifis...@gate.net -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Paul Ewins Sent: Wednesday, April 01, 2009 10:52 PM To: Pentax-Discuss Mail List Subject: Re: do any m42 adapters do auto stopdown? Yep, that has to be different. I did remember a couple of cases of a "different" M42 in the photo world - an early Adaptall type mount that is M42 x .75 and also a Schneider Componon enlarging lens that used an M42 x .75 retaining ring. Earlier and later versions of the same lens were different sizes (M39 and M50) which caused me much confusion. The Adaptall thread was the one that connected the various lens mounts to the lens rather than the lens to the camera. Paul > The tool page he reference was M42-5 not M42-1 > > JC O'Connell > hifis...@gate.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: do any m42 adapters do auto stopdown?
Actually, the reference chart was M42 x 4.5 tpi, which is mixing metric and ASA. Somethings not right there. It then goes on to describe the inch equiv. as 1.6535 x 5.64 inches. Your Pentax camera lens SM is 42 mm x 1 mm, as Paul said. I measured. On Apr 1, 2009, at 19:44 , JC OConnell wrote: The tool page he reference was M42-5 not M42-1 -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Paul Ewins Sent: Wednesday, April 01, 2009 9:23 PM To: Pentax-Discuss Mail List Subject: Re: do any m42 adapters do auto stopdown? M42x1 would be the same regardless of whether it is photographic equipment or heavy machinery since it describes a thread with a 42mm diameter and a 1mm pitch. There is no guarantee that something (other than camera equipment) described just as M42 wouldn't be M42 x 0.75 or M42 x 1.25, but I would bet that any M42 lens would be M42x1. Accrording to wikipedia Leica thread mount is M39 x 26tpi (whitworth) which works out at M39x.977. Apparently early Zorki and early Canon RF cameras used M39x1. It gets really murky in the world of large format lenses and shutters where some of the metric sizes are very close to imperial sizes and you need to measure very carefully to work out exactly what you have. Prior to WWII there weren't any real standards and lots of oddball sizes exist. Paul On a related note, is what we call m42 the same as what machinists call M42? http://www.besly.com/catl/catl4124ps.htm#M42 Yes, I think so. Leica screw mount is M39. Joseph McAllister pentax...@mac.com http://gallery.me.com/jomac http://web.me.com/jomac/show.me/Blog/Blog.html -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: do any m42 adapters do auto stopdown?
Larry Colen a écrit : The m42 lenses stop down by pushing in on the rod. The k-mount stop down by pushing sideways on a lever. I can imagine something where the widget that pushes sideway on a lever, would push on a hinged doo-hickey (pardon the technical engineering jargon) that then pushed on the rod on the lens. Does such an m42 to k-mount adapter exist? You can modify an adapter http://www.jr-worldwi.de/photo/index.html?M42_auto_adapter_Pentax_PK.html -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: do any m42 adapters do auto stopdown?
On Thu, Apr 02, 2009 at 06:57:22AM +0200, Michel Carr?re-G?e wrote: > Larry Colen a ?crit : >> The m42 lenses stop down by pushing in on the rod. The k-mount stop >> down by pushing sideways on a lever. I can imagine something where >> the widget that pushes sideway on a lever, would push on a hinged >> doo-hickey (pardon the technical engineering jargon) that then pushed >> on the rod on the lens. >> >> Does such an m42 to k-mount adapter exist? >> >> > You can modify an adapter > http://www.jr-worldwi.de/photo/index.html?M42_auto_adapter_Pentax_PK.html That doesn't couple the stop-down pin on the lens to the stop-down lever of the K mount - it's just for auto-aperture screw-mount lenses, to stop them down (all the time). Without that they'll always be at full aperture. That's why you generally want screw-mount lenses with an auto/manual switch; in the manual position the lens will stop down to the selected aperture. You still only get stopped-down metering, but at least you're not stuck at full aperture on the lens all the time. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: do any m42 adapters do auto stopdown?
Modifying the adapter is all about using auto only M42 lenses manually on a K body. I beleive this inquiry is if auto M42 lenses can be used AUTOMATICALLY via a complex adatper on a K body, which the answer is no. JC O'Connell hifis...@gate.net -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Michel Carrère-Gée Sent: Thursday, April 02, 2009 12:57 AM To: Pentax-Discuss Mail List Subject: Re: do any m42 adapters do auto stopdown? Larry Colen a écrit : > The m42 lenses stop down by pushing in on the rod. The k-mount stop > down by pushing sideways on a lever. I can imagine something where > the widget that pushes sideway on a lever, would push on a hinged > doo-hickey (pardon the technical engineering jargon) that then pushed > on the rod on the lens. > > Does such an m42 to k-mount adapter exist? > > You can modify an adapter http://www.jr-worldwi.de/photo/index.html?M42_auto_adapter_Pentax_PK.htm l -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.