[rogerg (Roger)]

I finally got around to buying a Astronomik clear MG filter for my CFW-8 filter wheel. This means I now have par-focal clear/un-filtered capability, which is great. I've found even the IR filter of the Astronomik standard set for CCD imaging take a huge punch out of the sensitivity of my ST7 to the point that I'd be happy to sacrifice the colour for the sensitivity.

I expect to largely use the clear on it's own - not combine it with RGB data. The clear suits my purposes of faint galaxy cluster hunting.

But if I were to use it with the IR cut RGB filters, does anyone have any advice? I expect I'm going to get data in the clear image that won't exist in the RGB, because the RGB's are IR cut. I suspect this might lead to the extra data again being lost because there's no RGB to represent it. I expect that I would use the clear as the luminance channel. I'll be interested to see what this means for the resulting image.

Anyway, I'm really happy to have the high sensitivity back ... enjoyed cruising around a few galaxy clusters and individual galaxies last night, taking 2-7 shots of each (5min exposures) just to see what's there, getting lot of faint stuff.




Roger.