NGC 3184

[Rodd]

I finally manged to capture a full data set.  This image was plagued by a little bit of every problem peculiar to astrophotography: clouds, fog, Moonlight, LP, bad flats, bad drivers, split cables, poor seeing,....to name a few.    I preservered through several false starts--having to throw out about 50% of the subs due to poor seeing and high FWHM values.  What I kept was pretty good for me--I think the image as a whole has a FWHM value of less than 2.5.  I don't achieve that very often--certainly not for all my filters in a data set.  I had to shoot Lum over many nights in efforts to get data as good as the other filters--otherwise using the lum data would not help.  I think I collected 187 and kept 92 lum subs.  As far as the data that I kept goes I am pretty pleased, though the blue and green channels were collected with high cloud that muddied the waters a bit.   I always think I need more data, but common sense tells me that 27 hours should be enough.  The palette gives me the greatest pause--it was very wan and gray.  I had to work really hard to get colors to show without bowing the image apart.  I think the palette may be a bit loud--especially the blue, but examples of this galaxy I have seen are not the most colorful--and blue seems to be the basic look.  The data I probably could use more of the most is Ha--I collected 40 300 sec subs and the night was so good I switched to lum to add to that channel under the assumption that 3.5 hours of Ha should be enough.  I always seem to lose some in the insertion procedure though--the Ha stack looked like it had a lot of potential. 

This is a crop taken with TOA 130 and ASI 1600.  All subs 300 sec Red: 80; Green: 56: Blue: 58: Lum 92: Ha: 40.   I used a super luminance composed of all Lum and RGB subs integrated together as a luminance.  In retrospect I think I was a bit aggressive with the crop. I should have processed the image fully than cropped so i would have both.  I cropped early though.  Oh well,  I am sure I will be processing this data for weeks to come.  I will have to be more organized in my processing.   I think this version is one that was binned 2x2 in software prior to cropping.  I had both an unbinnd and binned one and through the course of processing lost track of which was which--but Astrobin reports the pixel scale to by 1.57--so this must be the binned version

 

Edited February 24, 2020 by Rodd

[Stargazer33]

Very nice image Rodd!

Certainly sounds like you had a bit of a battle of attrition to get your subs! I think the end result justifies your sticking with it. As for 27 hours of subs!!! I dream of 27 hours view of a single object.

[Rodd]

1 minute ago, Stargazer33 said:

Very nice image Rodd!

Certainly sounds like you had a bit of a battle of attrition to get your subs! I think the end result justifies your sticking with it. As for 27 hours of subs!!! I dream of 27 hours view of a single object.

Thanks Bryan.  Yes, battle of attrition is a good way to put it.  It's rare I have the patience to shoot 60-70 subs for a filter (in this case lum) and not use them!  Bad weather came--then the Moon, and I had to wait.   But it made sense as the FWHM values for the RGB subs were around 2.5 (also rare for me)  and the lum subs were coming in at 3.4--not great for a luminance layer!    I have worked hard to learn to avoid the instant gratification button......of being in a rush to post.  It always leaves me feeling empty.....and the pages of the forum overloaded with revision!😄

Cs

Rodd

[Stargazer33]

I know what you mean. It seems like you should post the same day, or certainly within 24 hours of obtaining your subs sometimes. Normal day to day life comes first though, as it should. As long as I can get something that I'm not too unhappy with, I'm not too fussed about how long it takes.

Edited February 24, 2020 by Stargazer33

[Rodd]

1 minute ago, Stargazer33 said:

I know what you mean. It seems like you should post the same day, or certainly within 24 hours of obtaining your subs sometimes. Normal day to day life comes first though, as it should. As long as I can get something that I'm not too unhappy with, I'm not too fussed about how long it takes.

You mean life is supposed to come first?    Uh oh...that explains a bit! 🤔

[Rodd]

I Tweaked the palette and dynamic range....not much more to get I dont think.  Not sure more data would help....perhaps a lot more BETTER data would show,

 

 

Edited February 25, 2020 by Rodd

[Rodd]

I sharpened up the ridgelines of the spiral arms.  The overall palette is a bit murky, but I dont think I can do much better

 

[Rodd]

OK--I noticed my file size was only 249kb...something was wrog.  I acrewed up somewhere.  So I reprocessed teh image just to correct for this.  I did not bin this data set , though I did crop the image to roughly the same dimensions for easier comparison.  I think it is sharper and reveales more structure, though I think it needs a bit of smoothif at fine scales.  I am convinced there is no perfect image.  the question is, on balance, is this better than the previous.  The palette is a bit flatter--but teh details in teh spiral arms are more discernable.  Back to teh drawing board?

 

 

Edited February 27, 2020 by Rodd

[Stargazer33]

I think I prefer the one you posted on Tuesday with the tweaked palette and dynamic range to be honest. It looks more natural. The artifacts around the red giant towards the right hand side are also more apparent in the latest image. 

[Rodd]

4 minutes ago, Stargazer33 said:

I think I prefer the one you posted on Tuesday with the tweaked palette and dynamic range to be honest. It looks more natural. The artifacts around the red giant towards the right hand side are also more apparent in the latest image. 

I agree--the last one has already been deleted from my Astrobin page....What was I thinking?  The one you prefer is the final image.    I might be able to eek out a bit more....but I need to get away from it for a while.   Looking forward to M104.  I appreciate your input......I could have spent the next several weeks running around in circles...so thank you!

Rodd

 

[Stargazer33]

You're welcome. I know it is very hard to step away from something. You always think 'if I just do this or tweak that...' and that's when the wall falls down!  I believe that is a big problem for artists (painters etc.), knowing when to stop.

[Rodd]

1 minute ago, Stargazer33 said:

You're welcome. I know it is very hard to step away from something. You always think 'if I just do this or tweak that...' and that's when the wall falls down!  I believe that is a big problem for artists (painters etc.), knowing when to stop.

The ironic thing is, many times I will spend days reprocessing an image only to find that the best version ends up being a very early (rarely the first--but early) version. 

Rodd

[alan potts]

A lovely shot on the original, I feel you got a bit over saturated towards the end of the posts. Says he that always gets carried away with the colour controls.

Alan

[Rodd]

2 hours ago, alan potts said:

A lovely shot on the original, I feel you got a bit over saturated towards the end of the posts. Says he that always gets carried away with the colour controls.

Alan

I know.  The blue of the last couple is actually quite ugly.   
Rodd

[Rodd]

Thanks to Photogav, I have seen the light.  His spectacular M74 was what did it.  This iamge is not as "real" as his--but it is a step in teh right direction I think--for the most part, it was a matter f taming teh palette--the raher over powering blues.  I think this is more realistic

 

 

Edited March 6, 2020 by Rodd

[MarsG76]

Excellent result.... you definitely put a lot of effort into this masterpiece, well done.... we're aware of the challenges that plague us when we're imaging the heavens.

 

[Rodd]

5 hours ago, MarsG76 said:

Excellent result.... you definitely put a lot of effort into this masterpiece, well done.... we're aware of the challenges that plague us when we're imaging the heavens.

 

Thanks Mars. I am afraid this one is still driving me crazy.  It’s the palette. 
Rodd