The main thing is removing the IR block from the front of the sensor. Frankly, unless you are using this thing without a camera lens (as in, on a telescope at prime focus) I would not install a filter in the camera, but use one on the lens. This gives you the option of experimenting with different IR filters (with different nm cut-offs). If you are doing it for narrowband astrophotography purposes, then I guess it depends upon what you want to photograph (your target wavelength). If you want to do the above without affecting the focal plane, I believe that you need to replace the IR block filter with a clear glass of the same thickness.
720nm is the usual IR filter if you are doing monochrome daylight IR work. If that is all you plan to do with the camera, it would probably be a lot cheaper to install a small filter at the sensor as opposed to a big one to cover your largest lens. But your camera now has only one purpose. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
