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PixInsight => Gallery => Topic started by: IamTomzo on 2019 January 10 21:35:10

Title: First try with Rosette and PI - C&C welcome
Post by: IamTomzo on 2019 January 10 21:35:10
Greetings,

I got some clear nights last week and managed to get over 5 hours on Rosette.   I used darks, flats, and bias frames, all taken through an Orion 80ED with a modified Canon 300D with an Optolong CLS-CCD filter.   

I think my guiding was good enough and I am pleased overall with the data, but I am so new to PI that I am kind of hitting a wall on processing further.   Here is what I have done:

-   Batch preprocessed using calibration frames listed above.
-  I did a standard STF and applied it via HT
-   I did an iternation of DBE as there was a green cast around the edges.   Some of it is still there.

I did a few other "super stretch" efforts but I am confident those are probably a bit too much.

I have a couple of questions:

-   How can I bring out star colors?   Mine are all white, and I am sure that there must be some color in there somewhere.   I am not quite clear on the star mask method to get the colors out.
-   I would like to make the nebulosity pop a bit more but when I stretch I get other artifacts coming up.
-   I tried the color calibration tools but I am not sure I am getting the right colors here.

Any guidance is appreciated!

Here is a link to the image:

https://www.astrobin.com/385352/

Thanks

Tom
Title: Re: First try with Rosette and PI - C&C welcome
Post by: Geoff on 2019 January 11 13:04:43
Hi Tom
Detail is good.  I gave it a bit of a tweak with the saturation option in Curves, followed by SCNR. Couldn't do much more with a jpeg, but it may help to point the way.
Title: Re: First try with Rosette and PI - C&C welcome
Post by: IamTomzo on 2019 January 11 18:58:38
Thanks Geoff - that is extremely helpful.   I made those adjustments and it is certainly a big improvement.

https://www.astrobin.com/385484/?nc=user

I really like to have nice black background and in the past I have used Photoshop's dropper tool in the curves tool to set the black point.   This quickly makes a nice aesthetic look to an image.   Is there a similar tool in PI?

Tom
Title: Re: First try with Rosette and PI - C&C welcome
Post by: rdryfoos on 2019 January 29 12:06:08
Tom--great start.   I think you can drop your balack point a bit.  A good rule of thumb is to get the background space to a level of .8, .8,.8 to 1.0, 1.0, 1.0, values of the RGB channels in the image (bottom of screen.  It depends on what you have the settings at.  Mine are default.  Its out of 65,000.  Not sure how the number thoery works, but .8-1.0 is a good background.  Space is not black so don't go much below  .7
Rodd
Title: Re: First try with Rosette and PI - C&C welcome
Post by: IamTomzo on 2019 February 01 16:48:00
Thanks Rodd - the "space is not black" reminder is necessary.   For whatever reason, my primordial brain always wants that inky black background.   I think I am in for a rainy weekend, so perhaps I will make another run at this one!

I just ordered a CEM60 so my guess is that it will be cloudy for months now.....