I thought the were no matrix when using flash?
On Thu, 17 Feb 2005 08:55:02 -0800 (PST), Godfrey DiGiorgi <[EMAIL PROTECTED]> wrote: > Jens, > > My understanding is that in TTL mode, the Matrix mode exposure > evalution is working for the *ambient* portion of the light > metering, not for the flash metering. P-TTL allows an integrated > preflash/ambient exposure evalution based on both metering > capabilities. > > I could be wrong, I'm certainly no expert on this stuff, but > that's my understanding. It makes sense as the Matrix metering > evaluation is completed before the mirror swings up, since the > meter sensors' light is piped through semisilvered bits of the > mirror into the sensors at the bottom of the mirror box. > > Godfrey > > --- Jens Bladt <[EMAIL PROTECTED]> wrote: > > > BTW. If it didn't, linking AE to Focus Point wouldn't be > > possible for flash > > photography, would it. > > My test indicate that the area exposure differences due to > > different > > focusing distance, caused by choosing different (close or far) > > focusing > > points. I guess linking AF to Foucus point means more > > attention to the > > metered values in the parts of the matrix patern, close to the > > chosen AF > > point. > > > > > > Jens Bladt > > mailto:[EMAIL PROTECTED] > > http://hjem.get2net.dk/bladt > > > > > > -----Oprindelig meddelelse----- > > Fra: Jens Bladt [mailto:[EMAIL PROTECTED] > > Sendt: 17. februar 2005 07:50 > > Til: [email protected] > > Emne: RE: *istDS built-in flash overexposure problem > > > > > > Matrix works with TTL: According to the EXIF ibfo avaliable in > > the INFO > > menu, TTL flash will use matrix/pattern metering (*ist D), > > when an A or post > > A lens is used at "A"-setting. > > > > Jens Bladt > > mailto:[EMAIL PROTECTED] > > http://hjem.get2net.dk/bladt > > > > > > -----Oprindelig meddelelse----- > > Fra: Godfrey DiGiorgi [mailto:[EMAIL PROTECTED] > > Sendt: 17. februar 2005 00:43 > > Til: [email protected] > > Emne: Re: *istDS built-in flash overexposure problem > > > > > > My understanding is that P-TTL allows the camera to take a > > flash > > reading and use the full matrix exposure evaluation system, > > including whether you've linked the AF point to the exposure > > evaluation, where TTL flash only gives access to the CW > > Averaging meter pattern's exposure setting. > > > > I don't know which one will prove to give the best exposure > > with > > the greatest consistency, but from a purely technical point of > > view I'd consider the P-TTL flash system as being more complex > > or "advanced" compared to the TTL flash system. > > > > Godfrey > > > > > > --- Nick Clark <[EMAIL PROTECTED]> wrote: > > > It seems to me that so called advanced P-TTL is a cut down > > > version of proper TTL. It cuts the flash off a a > > predetermined > > > time based on the preflash exposure measurement, rather than > > > cutting it off due to measuring it during the actual flash > > > exposure. > > > > > > > > > > __________________________________ > > Do you Yahoo!? > > Yahoo! Mail - Easier than ever with enhanced search. Learn > > more. > > http://info.mail.yahoo.com/mail_250 > > > > > > > > > > > __________________________________ > Do you Yahoo!? > All your favorites on one personal page â Try My Yahoo! > http://my.yahoo.com > > -- ------------------------ Thibouille
