It should have the SR focal length set to 420mm; that's the only way it knows how angular rotation of the camera affects the position of the image on the sensor.
Unfortunately that's not possible with an AF lens mounted on a TC (such as the Sigma APO TCs) which passes the FA signals. This means I can't use SR if I'm using my my AF TCs :-( Pentax really need to come up with a way for the user to indicate that a TC is in use. It wouldn't be bad if they also eventually release an AF TC of their own (hopefully one that works with the new DA* lenses, while I'm dreaming ...) On Thu, Feb 01, 2007 at 01:26:07PM -0500, Kenneth Waller wrote: > Interesting. > But I wonder if, for example a 300mm lens with a 1.4 converter, should have > the SR set for a 300mm lens or 420mm (1.4 X 300) lens ? > > Any thoughts? > > > Kenneth Waller > > ----- Original Message ----- > From: "Godfrey DiGiorgi" <[EMAIL PROTECTED]> > Subject: Re: The need to manually set SR > > > > On Feb 1, 2007, at 4:47 AM, John Whittingham wrote: > >>> It's in the menus. I think in custom functions. But if you mount the > >>> lens and turn SR on before turning the camera on, the SR > >>> adjustment screen will appear when you turn the camera on. Just set > >>> it to 600. I've set it to 800 with my 400 and 2X converter. Works > >>> nicely. > >>> Paul > >> > >> > >> Ah now, is that an A series lens, or A series converter? Because > >> it's not > >> working with AF lenses and AF converter, it's just transmitting the > >> lens > >> data straight through and setting SR automatically, with no option > >> in the > >> menu structure to change SR, it's 'greyed out' so to speak! > > > > > > If the lens fitted supplies the focal length data, I don't believe > > there is any way to override the setting. That includes the lens plus > > teleconverter. > > > > Pentax-A Rear Converters do not supply the focal length data so you > > can set it manually. That's the only one I have. However, this topic > > came up on DPReview.com and one person posted his experience with the > > Pentax-F 1.7AF adapter and the Sigma 2x APO TC ... > > > > thread link: > > http://forums.dpreview.com/forums/read.asp? > > forum=1036&message=21831766 > > ----------- > > Forum DPReview.com "Pentax SLR Talk" > > Subject Re: Teleconvertors & anti-shake focal lengths > > Posted by McBrian [CLICK FOR PROFILE] > > Date/Time 6:44:59 PM, Saturday, January 27, 2007 (GMT) > > > > > > > > Hi all, haven't digested all of the thread, so sorry if I'm repeating > > anything, hope some of this may be of interest. > > > > I just received a Pentax 1.7x AF Adaptor today, got for a very very > > nice price and it's in as new condition too. I already have a Sigma > > 2x APO so I wondered how the K10D SR and EXIF differs between them, > > well here are a few quick conclussions. > > > > Penatx SMC-F 1.7X Adaptor > > When you mount an SMC-A lens to a Pentax-F 1.7x adaptor you are > > promted at switch on for the focal length, with the SMC-A50 f1.4 > > mounted the adjusted aperture of f2.8-40 is selectable/displayed in > > VF and EXIF, the EXIF also displays the focal length selected in the > > SR menu. MF is lit in the VF even though AF is selected, the lens > > does AF though. > > > > When you mount an F/FA/DA lens to a Pentax-F 1.7x after switch on you > > can set the desired focal length by going into the Shake Reduction > > menu and select whatever focal length you wish, with the DA16-45 f4 > > mounted the adjusted aperture of f6.7-40 is selectable/displayed in > > VF and EXIF, the EXIF also displays the focal length selected in the > > SR menu. MF is lit in the VF even though AF is selected, the lens > > does AF though. > > > > Sigma 2x APO > > When you mount an SMC-A lens to a Sigma 2x APO TC you are promted at > > switch on for the focal length, with the SMC-A50 f1.4 mounted an > > aperture of f1.4-22 is selectable/displayed in VF and EXIF. No > > corrections to Aperture but the focal length selected is displayed in > > the the EXIF. MF is lit in the VF even though AF is selected. > > > > When you mount an F/FA/DA lens to a Sigma 2x APO TC after switch on > > you cannot set the desired focal length, the Shake Reduction menu is > > greyed out, with an FA24-90 mounted the aperture range as stated on > > the lens is selectable/displayed in VF and EXIF, No corrections to > > Aperture or focal length in VF or EXIF > > > > If you switch on with only the Sigma 2x attached you are promted for > > a focal length but this is over ridden as soon as you attach an AF lens. > > ----------- > > > > So behavior will differ based on the teleconverter and the primary > > lens fitted. > > > > Godfrey > > > > -- > > PDML Pentax-Discuss Mail List > > PDML@pdml.net > > http://pdml.net/mailman/listinfo/pdml_pdml.net > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
