frank theriault wrote: > On Jan 27, 2008 5:36 PM, drew <[EMAIL PROTECTED]> wrote: >> Hi all, >> >> My mum always gives me a little money for my birthdays, this year I >> bought myself a little prezzie of an IR filter... Today I got a chance >> to get out and play. >> >> http://www.rileyelf.free-online.co.uk/IMGP5586aweb.jpg >> >> Any thoughts, comments etc. gratefully received. >> Pentax *ist-DL 18-55 kit lens. >> > > I like it. Very cool shot! > > cheers, > frank >
Thanks again for your thoughts Marnie, Boris, Frank and Mike. Yes, It is a bit of an odd effect Marnie, the sensor, of course is sensitive to IR and visible, and the 720nm filter does also transmit some visible light, but only the very deep reds. It's normal with digital IR to white balance off something that strongly reflects IR, like grass. but even with this, as the filter only passes red, everything that does not reflect IR appears as a red muddy colour. I cannot see why you could not use digital IR to diagnose trees Mike, the effect should be the same, there is not much variation in my picture because there are only a few evergreens in the foreground with leaves (or is that needles), the rest are bare. Different plants do appear to have different shades. I did a little page of explanation... http://www.rileyelf.free-online.co.uk/webir/webir.html Cheers, Drew. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
