H-alpha Coming-out in my Andromeda Galaxy image

[Daveskywill]

PS: I've got a Celestron rasa 11" version 1 and a qhy600ph-c astro camera
and use them together and with this Messier 31 image I took un-precedented
time see?

Here back in I think the 25th of August of this year, I took about 1-3 hours worth of Integration time of Andromeda through my 11" rasa and the qhy600ph-c (it my qhy600 still worked back then, need prayer for it too, to work good again or get something that does, it's not a problem of polar alignment either (apparently) as I used Sharp Cap Pro for my PA and had only a few arcseconds offset...) but this time I'd accomplished unprecedented Integration time on it as yet my best image of Andromeda had be done, in Michigan with a Nikon D800 (36mp) and cem60 (no filter) same kind of scope though 11" rasa version 1...But now I've got a cem120ec2 same scope, a qhy600ph-c (cooled astro camera with all-spectrum sensor with 16 bit a/d, 60 megapixels, also Full Frame like the D800) but I have suffered in this shot my un-Flat fielding issue as that is to be expected as I hadn't yet figured out All the issues with my Spike-A Flat...I'm still getting the color balance ok and making it dim enough...and then too I've got circular gradients around my stars and my Messier 110, No I don't really think it was an out-of-focus problem...So it wasn't a guiding problem either though I did use guiding and both axes...I don't think that did it...I'll give some close-up's of the Messier 110 and some of the 'un-focused-looking stars' Hope this helps...and God bless you all and Ruby and Eva and all my family and friends...Hope I get this figured-out: ps I know it has a green-hue apparently it is because of the L-pro filter and/or because there are more green pixels than red or blue too. I tried using HLVG but it kinda worked a little...I can show another one too.

PS: I'm real happy now! For the first time I've gotten 'reds' and 'reddish-hue' stuff apparently real Hydrogen-Alpha regions in my astro-photo...see And this was a Goal of mine (So cool) even though this isn't quite a Flat field I have hopes and plans of that too. You can tell that this isn't color replacement as I didn't mask certain stars and told it to make them reddish...here's my photoshop technique: 1st I cranked-up 'saturation' then 2 I found the sky back ground had a blue hue so I turned my levels channel to blue only and adjusted to cancel somewhat, then it had a greenish hue so I used HLVG a bit and then repeated the pattern until I got this result. So Cool, if I had the circular gradient-thing figured-out, More Integration Time still...and a Flat field plus Cranked-up More H-alpha regions then we'd be really truly-on, right? Just need some STC filter too to make filamentary regions come-out. Maybe.

What does everyone think?

I mean 1-3 hours of Integration time with a rasa 11" version 1 is what this, image of Andromeda, is from and a qhy600ph-c camera...but why is my H-alpha looking orange? I like pinks instead...can this camera come-up with that with its color gamut? I'm thinking it can but do I just simple answer need more total Integration time...just go for the max (like I said I was guiding the rasa with a good polar alignment) does anyone know what caused my stars to look bloated like out of focus?

Thanks

[Daveskywill]

I now too have a Radian Triad filter and I want to try to use my rasa 11" and qhy600 on the Rosette Nebula to the left of Orion and want to obtain the blue on the inside and orange on the outside-look. Also ps: I do have a lifetime subscription to PixInsight now...and am new to that but have a little experience with photoshop. So if anyone can do TeamViewer with me for PI that'd be neat or know of a Christian person who can that'd be neat...also I know we're basically off by 12 hours...so as long as we agree to figure that out...thanks for all you guys help. What do you think about a 12 arcsecond offset PA on my cem120ec2? is that good enough for the 620mm fl of my rasa? however I might include a 8" edge hd sct later once I buy it and RedCat...and know the edge would push the fl and slowness of optics and would be better for 'small' things in the sky through my qhy178 (which I already have that camera too) plan to piggy back all 3 or 4 of these scopes...don't worry the mount is such a behemouth that I think it can hopefully handle it...ps my email is davewilliamstar@live.com and phone number (269)625-3560 I'm from the states from northern Indiana so if you have a way of calling long distance...God bless take care clear skies. David

[Daveskywill]

Also my astro buddy friend who has experience with qhy cameras says that with the 16 bit depth of the 600 I need to keep my gain at 60 and my offset at 76 all the time...and too that I need to use 3 second Flats, and that I need Bias frames but I don't need them for the qhy178...he also said I needed 20 Flat and 50 Bias regardless of whatever Light frames I take...and the Darks need to be 1.5x the total number of Light subs. However by some different people off of cloudynights.com a northern hemisphere astro imaging forum said that the qhy600 needs Flat-Darks and no Bias and sometimes you can go a shorter exposure for Flats like down to .5 of less seconds...I know my astro buddy friend who i listed at the beginning of this also said i needed to use transluscent acrylic (white) to make my Spike-A Flat dimmer...I even had to resort to opaque acrylic as the rasa is optically so Fast and also I was tempted to remove my camera each time and take custom length Darks to match back at my 'Darker' home about 4 miles away from my observatory (ps: got a 2nd observatory now it's in northern Indiana with worse light pollution) but I figure I need to stick by a 5 second-interval-rule for Darks and make them match the Light exposure lengths to my available Darks, length...So I don't have to keep removing my camera, right? I do have light pollution of about Bortle 3.7 here inside Bremen Indiana where my mom and I live but out 4 miles from town where my observatory is, the Bortle is about 3.4 so a little darker. But still needs light pollution and/or narrowband filters. ps: I used an L-pro filter like I said...and ps: if I were trying to image Dark Nebulae, shouldn't I maybe 'crank my gain-up a little bit?' though I know that I have to match the gain in the calibration frames and the buddy friend said gain of 60 does it for everything...I realize the gain is a like iso on a dslr and the amplifier setting...so effects photons that turn into electrons ratio but I don't know if it messes with certain kinds of noise or not and the total signal to noise ratio if nothing else was changed. Also what is the maximum Great job a RASA scope can accomplish (from the longest total Integration time?) Thanks. David

[Daveskywill]

And too the gradient is in the Andromeda shot earlier with H-alpha regions



How do i remove a circular gradient (is it from compression?)

Should I use NIK utilities?

or Topaz AI?

or are either one good for that?

I already god NIK utilities on my photoshop just need to pay for it

It was the same Andromeda shot taken on August 25th 2022 with my qhy600ph-c and my Celestron rasa 11" about 2.5 hours of Integration time
L-Pro filter...

all on a cem120ec2 mount

ps: I've got a Samsung Galaxy S22 ultra smartphone with 8K 24fps ability.

And a Dell xps 8950 and Dell 8K monitor...and observatory.

[rustigsmed]

Hi David,

Nice work.
With modern cmos cameras you are better off taking flats slower rather than quicker. this is something to do with how they are processed in the camera. Perhaps check these videos out (think there are 3) https://www.youtube.com/watch?v=Kkg441UBNpo

to me the images have the following areas where there could be the most improvement:
- application of flats. don't seem to be working correctly - i'd revisit them.
- it looks like your sub exposures may have some of them out of focus slightly or perhaps the optics were affected by dew. (might be worth going through your subs and culling out any softer ones and then restacking).

once those two are sorted you'll be laughing and it will be much easier to process the images. :thumbsup:
as for the gradients on andromeda it looks like compression.

I hope that helps somewhat :thumbsup:

edit:
i did a quick effort to remove the flat gradient and it looks like if you can follow the solutions in the video i linked it probably should sort it out. (the removed gradient still results with the concentric circles as per the video - which indicates 'flats-with-modern-cmos issues')

[Daveskywill]

See, if your outer stars look like (field rotation, direction) then you are too
far away and out of Back focus and if you have radial trailing-look like Star Trek
going 'warp' then you are too close to primary mirror (or to inside of Back-focus)

So this applies to RASA scopes and as you can tell it could get confused as
field rotation the first thing or 'coma' the 2nd one...you know.

To an untrained person or even un-orthagonality. but I found that even when
I was mostly polar aligned and had autoguiding going both axes that there was
a 'field rotation-effect' sometimes with my RASA back in Michigan so now I know that I probably was too outside of Back focus. So back then I only
sometimes probably heard about this but didn't think too much about it.

Now I need to.

So I'll use a visual method examining the stars around the outer parameter.
and stop and lock it (though I'd like to try using a smaller camera for this rasa too not just the qhy600) but a qhy178 but the 178 has shorter back focus. So I might just piggyback my scopes and hopefully have both orthagonal trained and collimated all scopes...want to eventually piggyback 3 other scopes besides the rasa 11".
jpg was taken from a youtube movie about the RASA and Back focus.

Hope this helps.

[Daveskywill]

See?

[Daveskywill]

See?

This one's better quality

[Daveskywill]

See i'm using full spectrum and shooting with an L-pro filter and
it's a Celestron RASA 11" v1 scope

and after taking my 2.5 hours of integration time (which I solved the circular
gradient thing, i'd had it compressed like someone thought: thanks) but I was
too out of focus (which I think is more of a problem in this shot than out of back
focus though if the focus had been better maybe could tell more)

And I'm supposed to be able to see 'the red channel' So I was processing by
once stacked (with Darks and some Flat (sometimes though I've got to get figured-out Flats (see right now my qhy600 is getting worked-on in the Orient, so let's hope it get's back fixed, nice and soon?)...and I was told that I don't need Bias but I need Dark Flats (is that right for my qhy600ph-c?) and but Prost Processing I'd amp up the 'saturation' then the photo would be blue or green hue (if blue I'd adjust 'blue' in levels or if green would do HLVG in PhotoShop) until the photo showed some orangish stars in places that I didn't dream-up and decide to make them that way...and also the 'Core' of the galaxy was getting (even though blown-out: which you ought to see Russell Croman's (gradientxterminator website: https://www.rc-astro.com/galaxies.php & https://www.rc-astro.com/photo/id1214.html (the 2nd one on Andromeda, it's the most 'detailed version I've ever seen (a mosaic)) the first one is just his galaxies and nebulae) but using both Russell's equipment plus his processing skills it (both) allowed for the subtle 'spiral's' found in the core of the galaxy...and usually amateurs 'blow-out' this core when they (a: don't have such large apertures...and b: just don't mask the faint detail in their image (even if it Is a rasa or good scope) and run the 'curves or levels'-up (without masking every step of the way that would-ha' blown it out...And ps: doesn anyone know of any good Pixinsight skills for masking the faint detail? What is ABE or CBE (in PI)
ps like I said my skills are in PhotoShop and not PI...(yet)

Now I was instructed that an L-pro filter has bandpasses at H-alpha and O-iii
So that seems to make my think that 'yes' it is H-alpha that is the orange there (that is unless it is S-ii (which although is redder than H-alpha, is less prevalent in our skies as we see them, according to my friend)

but assuming there is some Sii close to Ha (how would I sort that out?)
thank you.

David.