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M51 final?

Started by hakescl, 05/24/2009 12:44PM
Posted 05/24/2009 12:44PM Opening Post
I am still spending too much time processing, so I should at least ask for feedback along the way. At least processing is something to do during all the recent rain. This may be the end of this M51 for a while, depending on your feedback to the following processing choices...

Fewer color subs - This version removed the "moon" RGB subs, and that appears to have fixed the weird gradients that I couldn't quite deal with in software. Still have 35 minutes each.

More contrast - Rather than continuing to fumble with curves, I just cranked the contrast slider over more than I normally would. Looking at other on-line shots, the ones with higher contrast seem to "jump out" more. Is this too much?

More sharpening - Again, more than I think looks "natural," but the result pops a bit more. Several iterations of unsharp mask here. I tried to be selective with stars, but I am sure I need more practice with that. Too much? (I have yet to do a "de-convolution" I like.)

More saturation - Once again more color than I personally like, but showing this to a few non-astro people, they like the vivid colors better. Again, too much?

Smoother background - With a Carboni action. I think it removes some of the faint background galaxies, but is the smoothness more visually pleasing?

Any comments and suggestions would be appreciated.

Thanks,
Charlie




Attached Image:

hakescl's attachment for post 46961

Fort Lewis Observatory: (37.238, -108.052) ~2360m (7744 ft.) elevation.
Darkness - typically 6.5+
Scope - Meade 16" LX200; f6.3 focal reducer
Focus - JMI Smart focus
Camera - SBIG ST-10XE; (~.5"/pixel)
Guiding - AO-8 and/or Meade 5"/DSI/PHD
http://www.fortlewis.edu/observatory
Posted 05/24/2009 02:36PM #1
Hi Charlie,
Some thoughts from the peanut gallery are below:

Charles Hakes said:

I am still spending too much time processing, so I should at least ask for feedback along the way. At least processing is something to do during all the recent rain. This may be the end of this M51 for a while, depending on your feedback to the following processing choices...

Fewer color subs - This version removed the "moon" RGB subs, and that appears to have fixed the weird gradients that I couldn't quite deal with in software. Still have 35 minutes each.
[COLOR="Teal"]*** I would gather more exposures before processing. Processing is much easier with better data. My hard drive is littered with objects that were abandoned in mid-processing because I realized that there was just not enough data to be able to produce a decent image.[/COLOR]
More contrast - Rather than continuing to fumble with curves, I just cranked the contrast slider over more than I normally would. Looking at other on-line shots, the ones with higher contrast seem to "jump out" more. Is this too much?
[COLOR="Teal"]*** Keep fumbling. A juggler doesn't start out by never dropping something. They fumble and drop, but, with practice, they learn how to do it. A contrast slider is a harsh adjustment. Most accomplished imagers never touch it, preferring the gentler and more selective curves.[/COLOR]
More sharpening - Again, more than I think looks "natural," but the result pops a bit more. Several iterations of unsharp mask here. I tried to be selective with stars, but I am sure I need more practice with that. Too much? (I have yet to do a "de-convolution" I like.)
[COLOR="Teal"]*** Yes, it's over the top as evidenced by the mottling in the blue and red channels and the stars with 'panda eyes' (especially in the red). Those artifacts are both signs of overagressive sharpening. Sharpening techniques work well on good data, i.e. with a strong S/N.[/COLOR]

More saturation - Once again more color than I personally like, but showing this to a few non-astro people, they like the vivid colors better. Again, too much?
[COLOR="Teal"]*** Yes, again too much. Trust your own judgement more. Pushing the saturation into cartoon-like effects doesn't do justice to your data.[/COLOR]

Smoother background - With a Carboni action. I think it removes some of the faint background galaxies, but is the smoothness more visually pleasing?
[COLOR="Teal"]*** I know it's easy to just run a Carboni action, but I feel that you would be better served by learning how to do the 'action' on your own. Not only would you have greater control of what's going on, but you would be learning more about processing and PhotoShop in the process.[/COLOR]

Any comments and suggestions would be appreciated. [/quote]
See what happens when you ask for comments. Be assured that they are given in a spirit of helping.
Simply stated, I think that a gentler hand in processing and more data will do your images a world of good.
My regards,

dan