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Now, like announced, these are my observations:
After having modified a canon300d last year by complete remove of the filter glass and, of course, resulting inusability for daylight photography, I tried to test the Baader BCF 40/400 replacement filter for the canon eos 40/400d standalone first, before dissassembling my new 450D.
IR LEDs from tv remote ctrls usually have emissions of about 850-950 nm wavelength, so - after the filter courves on different bcf-suppliers' websites - I expected a complete extinction of their light, but unexpectedly it shine practically unweakened through the baader filter.
Already slightly confused i made a second test and took a picture of my bathroom heater glowing dark red for the eye with the bcf put in a cardboard holder in the filterless 300d; it looked like a headlight on the photo.
Also, a shot out of the window showed the well-known orange coloured trees that can't be corrected to green with custom white balance - no difference with/w'out the bcf.
So I repeated the tests with that original part of the filter, that will stay in the cam ( that one with the ultrasonic dust cleaner piezo element) when modifying it.
Seems to me this one does the "real work" of blocking unwanted IR: The IRLED is significantly darkened and the trees look much "greener" ;-)
The now modified cam - bcf insert instead of the glued in second filter for maintaining the optical path length - takes nearly perfect daylight pictures, oK, the automatic white balance isn't really satisfying any more but that's not a real problem with RAW format.
Hope to have CS soon for a decent M27 or ngc 6960 take, but at the moment it's permanently cloudy here.
rudi
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