On Sun, Aug 29, 2010 at 10:46 AM, CheekyGeek <cheekyg...@gmail.com> wrote: > I have no experience with AF teleconverters, but have the MF Adaptall > 2 version of both the 2x and 1.4x that I planned to use with my 52B > 90mm f2.5 Macro SP. It will do 1:2 by itself and 1:1 with the 2x, so I > believe that means it will do 1:1.5 with the 1.4x. > > The main advantage of the 1.4x (to me) is that you are losing only a > stop of light instead of 2 stops with a 2x. Nice to have when that is > a factor. > > The Sigma EX 10-20mm f4-5.6 will also cover a full 35mm frame, at > least down to about 13mm. That probably makes it about the widest > rectilinear you can put on a film camera. > > Need to carve out some time to actually USE all the stuff I've been > accumulating. Your 1.4x to 2x image degradation comparison would be > interesting to do. > > Darren Addy > Kearney, NE >
The Sigma 12-24 f4.5-5.6 remains the widest FF rectilinear in most mounts (the other option being the Voigtlander Ultra-Wide-Heliar 12mm f5.6 in LTM, M or F mount). There's also their new 8-16mm version for APS-C but I doubt that covers FF at any focal length. Best deal on a real ultra-wide for FF is the Samyang 14mm f2.8, it's got a bunch of barrel distortion but is extremely sharp (and the distortion is easily corrected in post). It's available in KA form and branded as a Rokinon, Bower, Opteka, Falcon, Samyang and IIRC Vivitar Series 1. -Adam -- 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.
