If you can do that, the results are actually significantly better. The signal, being signal, does just add up. But the noise, being random, doesn't simply add; sometimes it's positive, and sometimes it's negative, so there is some cancelling.
In fact if you stack up N images you get N times the signal, but only sqrt(N) times the noise (strictly true only for a gaussian noise distribution, but in practice correct for just about any noise you're going to see in the real world). On Tue, Oct 31, 2006 at 02:01:13PM -0700, Tom C wrote: > I'm still going to wait and compare the noise based on side by side reviews. > > The full translation does come across better. > > It also is likely possible to reduce overall noise by shooting at shorter > exposure times and stacking images. The stack will stack up noise just like > it does with the signal, but if each stacked image is less than half as > noisy as it's double-ISO cousin, results could be favorable. > > Tom C. > > > > >From: Jack Davis <[EMAIL PROTECTED]> > >Reply-To: Pentax-Discuss Mail List <[email protected]> > >To: Pentax-Discuss Mail List <[email protected]> > >Subject: Re: K10D aimed as D200 killer/Translation of interview > >Date: Tue, 31 Oct 2006 10:57:23 -0800 (PST) > > > >Ditto! I'm sure it allayed noise concerns for many and especially those > >who might have designs on astro-photography. > >Did it help, Tom? > > > >Jack > > > >--- Joseph Tainter <[EMAIL PROTECTED]> wrote: > > > > > Ken, this is wonderful information. Thanks very much for the > > > translation. You are a great asset for us. > > > > > > Compressed RAW? This is news. > > > > > > I assume that in Japan there have been discussions of noise levels at > > > > > > high ISO in the K10D, just as there have been here. I interpret this > > > interview as an attempt to quell the concerns and speculations that > > > have > > > been going around. I know many list members have been bothered by the > > > > > > expression of these concerns, but guess what? I suspect that our > > > expressions of concern got our famously uncommunicative company to > > > scatter a few more crumbs of information our way. > > > > > > I note the point about tone gradation in the samples posted on Pentax > > > > > > Japan's web site. But without comparative samples of the same subject > > > > > > taken with, say, a 12 bit A/D converter, I can't tell yet just what > > > the > > > 22 bit converter will give us. > > > > > > Joe > > > > > > -- > > > PDML Pentax-Discuss Mail List > > > [email protected] > > > http://pdml.net/mailman/listinfo/pdml_pdml.net > > > > > > > > > > > > >____________________________________________________________________________________ > >Cheap Talk? Check out Yahoo! Messenger's low PC-to-Phone call rates > >(http://voice.yahoo.com) > > > > > >-- > >PDML Pentax-Discuss Mail List > >[email protected] > >http://pdml.net/mailman/listinfo/pdml_pdml.net > > > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
