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NGC2903 - last one of the season


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In the first half of April we had a few nights with clear skies, so I aimed my rig at the galaxy that Messier missed ...

60 x 80 and 120 second light frames (total integration time approximately 90 minutes), bias frames and flats

Imaged over 2 nights; 2/3 of the frames ended up being permanently archived ...

Equipment as per my signature. As always, unguided.

Processed entirely in Pixinsight.

This is still a WIP, TGVDenoise mottled the background and I'm still trying to find the right mix of edge protection and local support.

ngc2903.png

... and solved with Pixinsight. Note that the image solver in Pixinsight marks the galaxies that should be there, not just the ones you can actually see.

ngc2903-ann.png

Comments / suggestions welcome

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Noise is always an issue. Try ACDNR with a gentle deconvolution or multiscalemediantransform but I'm sure you know this- more to help the uninitiated in these matters. I find that the only way to really deal with noise is more signal- lots of signal!

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Thank you, Laudropb and pyrasanth.

More data is always the right answer, but unfortunately my current setup doesn't allow long exposures. Will try to remedy that after the summer.:headbang:

Multiscale noise reduction would also work, the trick is to preserve detail in the galaxy.

I already got better results simply by not pushing the intensity and saturation as much. It's all about subtle improvements and proper masking.

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