SteveNickolls

Hi Ian,

How are you getting on with your latest book? I’ve not found anything yet on the Internet giving anything near an insight into the reasoning beneath the workings of DSS. I have however come across these-

(A) http://www.stevebb.com/deep_sky_stacker.html

(B) https://markwalkerscreenwriting.wordpress.com/deep-sky-stacker-tutorial/

which are worth a read.

Like most guides they are output driven with little to no understanding of the inner workings, by that I mean you are instructed to do steps 1,2,3,5,6,4 and only in that order to get ‘x’ out. I was interested that in (A)  it suggests a high ‘Midtone’ setting could exacerbate halos around stars (non-apo’s also do this), I will look into this claim as I am not sure what the default value is.

In the same guide he does alter the RGB values but then he is not putting the resultant working image into StarTools.

The person writing Guide (B) also adjusts the RGB values in DSS then uses the working image for subsequent processing in StarTools. He does acknowledge other views on this. Is it all down to personal taste?

(C) There’s also this site- http://astrophotolinks.com/category/dss/

Which has links to advice on using DSS that you might want to explore.  So far I have only watched one of the videos which was a little long winded but the whole site looks like it could be a useful source of knowledge on DSS and maybe some of the users also then process in StarTools (can only hope).

I had a look into the ‘No EQ Cchallenge’ thread on SGL you provided a link for Ian and it is informative to compare some of the exposure values used against the resultant image. I think in the future for non-cluster shots I will aim for as many exposures as I can in a session and readjust objects into the centre of the FOV as necessary which will be fine for those objects actually visible in the telescope finder/’live view’ screen. Alternatively a very close guide star could be similarly employed where one exists.

How do you like the new SGL site? Not really had much opportunity to browse yet today but I notice there is a new ‘Imaging-Deep Sky’ section. Unsure over the new font, a little thin to my poor eyes and I prefer the previous.

I have been doing some hands on activity with my Flame Nebula data which I have processed in DSS both without adjusting the RGB, luminance and saturation settings and then with adjustment of them and the resulting image comes out better from ST if DSS has adjusted the RGB and luminance values. Adjusting in DSS has removed whole areas of false colour created in the image by ST which previously I had to crop out. I have also noticed that DSS can affect the bloom around stars and halos dependent upon how you tweek the ‘Midtone’ and ‘Highlight’ sliders. I will give attention to this in future. Where this leaves matters I really don’t know. There’s so much left to read up in the links above.

Cheers,

Steve