NGC 1760 in LRGB

[DiscoDuck (Paul)]

Finally got some colour data so could try LRGB instead of my previous LOSC effort on this.

Still getting to grips with LRGB imaging after only a few months with a mono camera. Interesting how different this is to the LOSC image, i.e. colour is much more understated and the bright sections are different.

Probably should've picked a better broadband target as the number of stars in this image is ridiculous

Higher res on Astrobin here.

Thanks for looking.

Paul

[billdan (Bill)]

Hi Paul,

There is a big difference between the LRGB and LOSC versions. I think I prefer the LOSC version as it looks more natural???.
How did some of those pinky areas in the LOSC turn into yellow in the LRGB version??

Very interesting though, I would not have thought that the difference would be that substantial.

[Placidus (Mike and Trish)]

Both images are pleasing. Well done on both.

Differences between images: Generally the difference will be down to incorrect calibration. Example of where this is not possible: Suppose camera A had an H-alpha filter only, and camera B had an OIII filter only, there would be no way that you could make the two images look the same. But suppose instead camera A had a high QE for red, and an efficient red filter, but camera B had a low QE for red and an inefficient filter, so long as the bandpasses were reasonably overlapping (ie not like OIII and Ha, which are mutually exclusive) it should be possible to calibrate the two images to look pretty similar in the red. Same argument for green and blue.

Under other conditions, incorrect removal of different moonlight or sky gradients can also produce apparent differences between images.

(I recall that you did add some H-alpha data for one of the two versions of the original image, so that could explain some of the difference at least for that particular version).

It makes complete sense to combine the data from the two images. Then you would have an even better image.

Best,
Mike

[DiscoDuck (Paul)]

Originally Posted by Placidus

Both images are pleasing. Well done on both.

Differences between images: Generally the difference will be down to incorrect calibration. Example of where this is not possible: Suppose camera A had an H-alpha filter only, and camera B had an OIII filter only, there would be no way that you could make the two images look the same. But suppose instead camera A had a high QE for red, and an efficient red filter, but camera B had a low QE for red and an inefficient filter, so long as the bandpasses were reasonably overlapping (ie not like OIII and Ha, which are mutually exclusive) it should be possible to calibrate the two images to look pretty similar in the red. Same argument for green and blue.

Under other conditions, incorrect removal of different moonlight or sky gradients can also produce apparent differences between images.

(I recall that you did add some H-alpha data for one of the two versions of the original image, so that could explain some of the difference at least for that particular version).

It makes complete sense to combine the data from the two images. Then you would have an even better image.

Best,
Mike

Thanks Mike. Makes sense. Re the H-alpha in the LOSC image, that was only a small amount and made very little difference.

What a great idea to combine them both. Gives me a task for those rainy nights!! (and a chance to undo some of that oversharpening in the OSC data).

Originally Posted by billdan

Hi Paul,

There is a big difference between the LRGB and LOSC versions. I think I prefer the LOSC version as it looks more natural???.
How did some of those pinky areas in the LOSC turn into yellow in the LRGB version??

Very interesting though, I would not have thought that the difference would be that substantial.

Yeah. Puzzled me a bit. But there does seem to be some green wisps in the centre at the bottom which suggests some OIII around. I guess that, if present in the bright areas, could give some more white/yellow areas. No idea why the colour camera would miss those - unless as Mike suggests I went a bit mad with gradient removal before (and things like SCNR in PixInsight).