ngc2403 lrgb

Another few nights successful imaging over the last week. I’ve not yet upgraded to the new Beta but I am following progress closely. I must say Ken & Jared are working tirelessly to finalse 2.4 helped along by all those posting feedback - it looks like it is going to be great.

Anyway I hope you like this galaxy.

Thanks for looking.



Very nice especially the star colors. I have the same CCD as yours and I think I need to reduce the sub-exposure times myself because this CCD appears to be extremely sensitive and my typical sub-exposure times of 10 minutes each is probably too long. I also captured this galaxy last month but did not capture as much star colors as yours.

Great image!!!


Very nice Barry. I was glad to see your result as I am currently imaging this galaxy as well (first clear night in MANY months). I’m also using the same CCD (SX Trius) and this will be one of the first RGB images I’ve taken with it. Do you process with PixInsight?

Peter, why do you think your sub exposure time of 10min is too long? If your skies support it that’s a good exposure length.

Hi Joel,

My light pollution is pretty high and I found that reducing from 10 minute sub-exposure time to about 7 minutes to work well in my area. 10 minutes sub-exposures seem to make most stars too white thanks to bright lights from nearby casinos. My 10 minutes sub-exposures of the same galaxy as Barry’s appear to be too long. His sub-exposures are 5 minutes which tells me that Sony ICX-694 CCD is quite sensitive. I have no idea whether Barry’s site is darker than mine but my latest capture was 7 minutes sub-exposure of a different galaxy (NGC 2903) seems to work well for my location. Your location may vary and if your location is darker than mine then you should be able to image longer without side effects.


Yeah that all makes sense. I suspect my skies are a little darker than yours, but I still need to get a feel for this camera and how it behaves.

Hi Joel

Yes, exclusively PI on my iMac. I do have PS3 on my observatory pc, but it’s such a fag swapping in and out during processing. I also find PS bewildering having used PI for a couple of years now. I’m more than happy if you want to PM me to talk PI processing.

I searched on Astrobin for NGC2403 and decided on 600s for my Lum. I had used this length before on M78 and also on an unprocessed NGC1333; but both of these would benefit from 900s I think, although I’ve not tried that duration. I am lucky being on the edge of a town in south Devon, UK, which has, in general, low light pollution being substantially rural.