On 14 Jan 2004 at 21:09, Willem-Jan Markerink wrote: > > Btw, mounting quasi-permanent filters inside the camera, behind the > > mirror, is quite common for analog IR-photographers; up to 0.5mm > > thick filters fit nicely between the film rails (allowing a sturdy > > yet flexible quality of filter)....:)) > > > > http://www.a1.nl/phomepag/markerink/btfr_fil.htm > > Btw, after seeing the typical shutterspeeds of the two sample images > (different filter (#87/b&w vs #89B/color), same exposure index), I > realised that such a filter *inside* the camera is only half as > relevant for a digicam compared to an analog camera....with 2s > shutterspeed, you need a tripod anyway....and given a tripod, it's > less problematic to use opaque filters in front of the camera (in > particular sliding filters a la Cokin). > > Also: it seems those older dedicated-IR camera's (like DCS3ir) at > least had the benefit of a sufficient exposure index (400-1600 ASA > IIRC)....otherwise they could never been used for aerial photography. > > Therefore: the claim that *current* digicam's make IR-film redundant > is rubbish....they once did, but do not any longer....;)) (couldn't > use a digicam on skiing trips (no tripod) either)
Overlooked the rather interesting exposure spec's on http://www.irdigital.net/ : 200ASA, 1/[EMAIL PROTECTED] (hmm....that's conflicting, with 200ASA SunnySixteen says 1/[EMAIL PROTECTED], or almost 1/[EMAIL PROTECTED] cq a true 1/[EMAIL PROTECTED]). Which means that regardless of whether D30 or D60 *can* record IR, there is still a very strong IR-block filter inside....perhaps the difference beteen D30 and D60 is in that filter, or in the chip.... Let's CC this to the Aerial Photography Mailinglist too, perhaps anyone there has experience with modifying current (high-end) consumer-digicam's this way? Not just IR, but high-speed IR? Fit for aerial use? -- Bye, Willem-Jan Markerink The desire to understand is sometimes far less intelligent than the inability to understand <[EMAIL PROTECTED]> [note: 'a-one' & 'en-el'!] * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
