Re: SDM repair complete
Adam, I'm afraid micro motors do not permits full time MF correction per se. Canon uses (used?) cheap micro motors as well in a couple lenses like Canon 50/1.8 and thiose lenses do NOT provide manual focus override but using the AF/MF switch on the lens. AFAIR, the Tokina/Tamron with built-in motors do not permit MF override either. -- Thibault Massart aka Thibouille/Thibs -- Photo: K-7, Sigma 28/1.8 macro, FA50/1.4, DA40Ltd, K30/2.8, DA16-45, DA50-135, DA50-200, 360FGZ ... Laptop: Macbook 13 Unibody SnowLeo/Win7 Programing: Delphi 2009 -- 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: SDM repair complete
Actually, you can do full-time MF with micro-motors, you just need to use a clutch mechanism like the Canon 50/1.4 USM uses. IIRC the micro-motor SDM lenses do this also (and it's the same setup as with the screwdriver DA lenses with QSF). There is no inherent FTM focusing unlike with ring-type USM. -Adam On Sat, Feb 6, 2010 at 11:16 AM, Thibouille pentaxl...@gmail.com wrote: Adam, I'm afraid micro motors do not permits full time MF correction per se. Canon uses (used?) cheap micro motors as well in a couple lenses like Canon 50/1.8 and thiose lenses do NOT provide manual focus override but using the AF/MF switch on the lens. AFAIR, the Tokina/Tamron with built-in motors do not permit MF override either. -- Thibault Massart aka Thibouille/Thibs -- Photo: K-7, Sigma 28/1.8 macro, FA50/1.4, DA40Ltd, K30/2.8, DA16-45, DA50-135, DA50-200, 360FGZ ... Laptop: Macbook 13 Unibody SnowLeo/Win7 Programing: Delphi 2009 -- 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. -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- 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: SDM repair complete
Adam Maas escribió: Is Pentax using Micromotors in all SDM lenses? Or just the dual-drive DA*'s and the 17-70. Note that ring-motors aren't inherently better, they're potentially faster and have full-time manual focus built-in, at a major cost in size. Micro-motors are much smaller. AFAIK, all the first SDM lenses use micromotors. I don't know if the more recent models use ring motors, but I doubt it. Carlos -- 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: SDM repair complete
John Celio escribió: Hopefully the technician didn't shoehorn a Sigma motor in there somehow. ;) Sigma uses ring motors in their HSM lenses. They are better than than the micro motors Pentax use in SDM lenses, I'm afraid. Carlos -- 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: SDM repair complete
On Thu, Feb 4, 2010 at 5:17 AM, Carlos R carlos_r...@teleline.es wrote: John Celio escribió: Hopefully the technician didn't shoehorn a Sigma motor in there somehow. ;) Sigma uses ring motors in their HSM lenses. They are better than than the micro motors Pentax use in SDM lenses, I'm afraid. Carlos Is Pentax using Micromotors in all SDM lenses? Or just the dual-drive DA*'s and the 17-70. Note that ring-motors aren't inherently better, they're potentially faster and have full-time manual focus built-in, at a major cost in size. Micro-motors are much smaller. The only maker to use both types of motors and differentiate between them is Sony btw, with all SSM lenses being ring-type USM and all SAM lenses being micro-motor USM. Sigma does micro-motor AF and ring-type USM, but no micro-motor USM. Nikon doesn't differentiate and Canon differentiates by the presence of a DoF/focus distance scale (with the 50/1.4 USM being a special case), Tokina and Tamron just don't do USM at all. -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- 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.
SDM repair complete
Just got my DA* 16-50 back from Pentax's outsourced service center (C.R.I.S. Camera Service, in Arizona). They did a terrible packing job with the lens, letting it float free in a box of styrofoam peanuts that wasn't completely full. UPS managed to smash up the box pretty bad, but thankfully didn't appear to hit the lens itself. Front element had a weird, oily haze on it. Might have been from the plastic bag the lens was in. Cleaned up alright, thankfully. Mounted the lens and the SDM worked immediately (you may recall my lens used to take 10-20 seconds for the SDM motor to activate previously). The AF even seems a little faster than before. Woo! Receipt said they replaced the HSM (Hyper Sonic Motor). Hopefully the technician didn't shoehorn a Sigma motor in there somehow. ;) John -- http://www.neovenator.com http://www.cafepress.com/jacelio -- 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: SDM repair complete
- Original Message - From: John Celio Subject: SDM repair complete they replaced the HSM (Hyper Sonic Motor). Hopefully the technician didn't shoehorn a Sigma motor in there somehow. Are you sure about that? William Robb -- 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.
