On Sun, 29 Dec 2002, Herb Chong wrote: > >So what I'm wondering is, how does TTL flash work without the flash > >having any information about the distance to the objects being > >illuminated? > it does on an AF body. the camera knows how far away it focused on > something.
But this distance info is not used in Pentax TTL or P-TTL flash system. The original TTL does not need distance info (see Bob S. reply on the same thread for how TTL works). P-TTL uses a pre-flash and the 6 segment metering; and it is also lens type independent. One of the flash systems I know of which uses distance info is Nikon's 3D Matrix flash system. -- --Lawrence Kwan--SMS Info Service/Ringtone Convertor--PGP:finger/www-- [EMAIL PROTECTED] http://www.vex.net/~lawrence/ -Key ID:0x6D23F3C4--
