Allow me to jump on this just to make a couple low ISO points. Accomplishing the same thing with filters is inconvenient and has its pitfalls. Filters may well cause flare and two more surfaces for light to penetrate almost certainly results in some image degradation. Relegating same to "insignificant" is not the option of anyone but the shooter.
Jack --- On Wed, 11/10/10, Matthew Hunt <[email protected]> wrote: > From: Matthew Hunt <[email protected]> > Subject: Re: K-5, K-7, side-by-side at ISO 6400 > To: "Pentax-Discuss Mail List" <[email protected]> > Date: Wednesday, November 10, 2010, 9:10 AM > On Wed, Nov 10, 2010 at 10:49 AM, > Mark Roberts <[email protected]> > wrote: > > >>OK. Can you expand on that? What is it about lower > ISOs that make them > >>primarily better to you? > > > > Longer shutter speeds. > > Suppose you have two hypothetical cameras: > (a) Minimum ISO 80, dynamic range of 12 EV at minimum ISO > (b) Minimum ISO 100, dynamic range of 14 EV at minimum ISO > > Which of these allows a longer exposure of a given scene > without > clipping the highlights? I don't know the digital ISO > standard very > well (and, from the looks of the Wikipedia article, it's > inherently > clear as mud, with several options available to the > manufacturers), > but it seems quite possible to me that (b) allows the > longer exposure > by having more headroom. > > So I think "lower minimum ISO = longer exposure" may be an > oversimplification. The K-5's large dynamic range may have > a more > beneficial effect for your shooting than its low minimum > ISO does. > > -- > 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.
