It could very well be that there is a limited range Of possible ISOs and that it's not worth losing The most sensitive end to "gain" slower speeds. Like I said, you can always add neutral density filters If the camera is too sensitive in certain situations, But if it's not sensitive enough, you are S O L Because there is no "reverse" neutural density" filter To make the camera more sensitive. Most people want The opposite when all else is equal, camera/film speed allows Faster shutter speeds. smaller f-stops, which often Combine to produce sharper pictures when shallow DOF Is not needed. jco
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of John Forbes Sent: Wednesday, November 01, 2006 5:38 AM To: Pentax-Discuss Mail List Subject: Re: Designing a Sensor Yes, I accept that you can use ND filters, and I accept that good studio flashes can be turned down very low. However, mine were bought on the cheap, and don't go low enough, and I'd rather be able to control sensitivity by adjusting ISO than by adding filters. The fact is that I seldom use higher ISO than 200 or 400, and never 3200. So for me, lower ISO would be better. John On Wed, 01 Nov 2006 09:02:51 -0000, J. C. O'Connell <[EMAIL PROTECTED]> wrote: > You can get neutral density filters for those rare cases > Where you want to use extremely wide f-stops. > I say rare because slr cameras have very fast shutter speeds for > Daylight usage and any decent studio flash is going to > Have many power settings including very low ones. If & when you > Hit those limits though, the neutral densities can > Solve that problem for you..... > jco > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of > John Forbes > Sent: Wednesday, November 01, 2006 3:45 AM > To: Pentax-Discuss Mail List > Subject: Re: Designing a Sensor > > On Wed, 01 Nov 2006 04:02:45 -0000, J. C. O'Connell <[EMAIL PROTECTED]> > > wrote: > >> My guess would be the sensor "base" speed is the speed >> At which no extra light ( slower sensor speed ) will improve >> The image quality any signifigant amount. No sense in >> Going slower if it doesn't improve anything. > > If you are shooting with studio flash, and can't turn it down low enough > > to give you short DOF, then there is a very good reason to have lower > ISO, > whether or not it improves the quality. > > Same goes for bright daylight. It's purely a theoretical concept in the > > UK, but in other countries one wishes one could reduce the light > intensity at times. > > John > -- Using Opera's revolutionary e-mail client: http://www.opera.com/m2/ -- 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
