The problem is most likely that we are talking extreme retrofocus designs because the focal lengths are very short yet the old 45.5mm registration distance left over from FF still remains on these APS Pentax DSLRs. I bet the wides are better on 4/3 or micro 4/3 formats because they have much shorter registrations relative to the sensor size.
JC O'Connell [EMAIL PROTECTED] -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of P. J. Alling Sent: Saturday, November 15, 2008 2:38 PM To: Pentax-Discuss Mail List Subject: Re: Wide zoom (and not zoom) lenses redux and yet Canon is know for having fairly poor W/A offerings, and the major knock against Nikon is that they haven't redesigned their prime lineup since the late `1960's. Let's just face it wide and ultra wide solutions on miniature formats are difficult. Boris Liberman wrote: > Hi! > > So here is the list of some lenses that I thought about recently and > the considerations that may prevent me from buying them. > > 1. SMCP DA* 16-50/2.8 - serious distortions at wide end, quality > control issues still there > 2. SMCP DA 17-70/4 SDM - some say it is a sibling of SMCP DA 10-17 > fish eye wide end distortion-wise. Perfect otherwise. > 3. SMCP DA 16-45/4 - slightly less distortions at wide end, basically > ok, though the CAs could be a problem. > 4. Tamron 17-50/2.8 - suffers from curvature of field, rather good > otherwise > 5. Sigma 18-50/2.8 - well, I just don't quite like Sigma, and certain > people call Sigma really nasty names > 6. SMCP DA 21/3.2 AL Limited - excellent lens, just not wide enough > 7. Tamron 17-35/2.8-4 - covers full frame, but also suffers from > curvature of field > 8. Sigma 17-70/2.8-4.5 - well, another Sigma > 9. SMCP FA 20-35/4 - said to be excellent, but expensive and starting > to become quite rare these days. > > No matter how strange this sounds, but it seems that there is no > decidedly good lens in 16(17,18)-45(50, 70) range for modern Pentax > DSLR. Each lens has some serious drawbacks. > > So here you have it - a short summary. Please don't kill the scribe. > > Boris > > P.S. I already have 21 ltd, it is listed here just for sake of > completeness. > > P.P.S. I should watch for reviews of DA 17-70/4 and some sample shots > as well. > > P.P.P.S. The price on (even brand new) DA 16-45/4 has gone down > considerably now... > > 4P.1S. I have placed an order for Tamron 17-50/2.8 and I may still buy > one for lack of better alternative due to its speed and sharpness. > Having excellent sample of Tamron 28-75/2.8 has its impact on my > reasoning... > > -- > 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. > > -- You get further with a kind word and a gun, than with a kind word alone. --Al Capone. -- 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. -- 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.
