On Aug 30, 2010, at 4:40 AM, Igor Roshchin wrote: > > > Larry, > First of all, 20/1.8 with x1.4 will be close to f/2.5 if I am doing the > math right at this ungodly early hour.
It's kind of silly to put a 1.4x on a 20 rather than just using my 30, or just using the 20 on my aps-c. The 1.4x would be for my longer lenses, though it could be handy for putting on my 16-50 when I'm shooting at the dojo and really need a 24-70. > SEcond, while I don't have experience with Tamrox TCs, > I have been happily using Pentax's MF 2x-S and "AF" x1.7. > > I just wanted to remind that the TCs can also be used with a macro > lens, making it "super-macro". This conversation reminded me that the TCs that came with the 300/2.8 would work with my tamron adaptall macro, which only goes to 1:2. > > Here is what DAF 100-MACRO with 2x-s and AF-1.7 stacked together > can do with a raspberry: > http://www.komkon.org/~igor/PHOTOS/Raspberries/100-2_0x-1_7x/IMGP9609.jpg > http://www.komkon.org/~igor/PHOTOS/Raspberries/100-2_0x-1_7x/IMGP9608.jpg Very fun. > > Igor > > > On 29 August 2010 00:47, Larry Colen <lrc at red4est.com> wrote: >> I probably got it when I bought someones bag of gear, saw that it was >> a TC and just tossed it in the drawer without looking at it. >> >> I just tried it out and it seems to work fine on autofocus. Does >> anyone have any experience with one of these? Would it degrade an >> image less than cropping it by a factor of 1.4? >> >> Another cool realization I had was that my Sigma 20/1.8 will work just >> fine on a K1000 body that I've got lying around, and it'll give me a >> view that is wider, and faster, than my 16-50 on the digital body. >> Albeit, that ASA 400 film doesn't seem to be nearly as good as ASA 400 >> on the sensor. >> >> In any case, it should be fun to play with. > > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- Larry Colen [email protected] sent from i4est -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
