If you can find the MTF charts for each lens, it will tell you all you need to know about what aperture it is sharpest at.
On Mon, Jun 4, 2012 at 6:22 PM, Larry Colen <l...@red4est.com> wrote: > I was thinking about my quest for sharpness, and was considering trying to do > some research into what the aperture "sweet spot" is for each lens, and was > wondering if anyone had already made a chart of them. > > Then I wondered how much it really matters. I've heard "a couple of stops > down from wide open", "anywhere between f/8 and f/16", and a couple other > rules of thumb. I do know that on some lenses, particularly the FA50/1.4, > that stopping it down a couple of stops from wide open, makes a huge > difference. And I suspect that if you look on an MTF chart, you might be > able to easily see the difference between f/4 and f/8, but is there a > practical noticeable difference? > > There is also the question of sharpness at the critical focus distance, and > overall sharpness. That a lens might be sharper at f/4 than f/16 at the > focal distance, but with a lot more depth of field, more of the photo will be > sharper at f/16, than at f/64. > > I'm primarily interested in answers based on personal, practical experience, > rather than theory. My hunch is that as long as I'm not too close to wide > open, or pushing diffraction limits, optimizing aperture for sharpness is not > the most productive place to spend my time and energy. That I'm generally > best optimizing the aperture for the picture, and not trying to optimize the > aperture for MTF. > > -- > Larry Colen l...@red4est.com sent from i4est > > > > > > -- > 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. -- David Parsons Photography http://www.davidparsonsphoto.com Aloha Photographer Photoblog http://alohaphotog.blogspot.com/ -- 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.
