On Thu, Feb 19, 2009 at 6:44 PM, Christian <[email protected]> wrote: > Larry Colen wrote: > >> Another factor that also played a part is the 20km or so of atmosphere >> that I was shooting through: > > Yeah I guess I wouldn't be doing those kinds of images. Atmospherics are > always a problem. > >> I certainly don't claim that the experiment was definitive. About all >> that I proved was that if you don't do it right, teleconverters won't >> improve the image quality. The next step is to figure out "what doing >> it right" is. > > Teleconverters, by default, always DEGRADE image quality; never improve it. > Anytime you put something between your lens and your camera you are going > to lower image quality. The question is: by how much? With matched > converters like I have, not by that much, but with crappy third-party > inexpensive TCs you are going to suffer greatly. >>
That's not always the case. Putting a 1.4x or 1.7x converter on the Nikon 70-200VR for example actually improves IQ due to the weakness of that lens at the edges on Full-frame. Since the TC essentially crops out the edges of the lens's image circle, the overall IQ is actually better. -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- 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.
