Richard:
I am a little disappointed with what i m getting as a result, I seem to always be at odds between sharpness and noise. I certainly dont want my pictures to look artificial but i would like smooth pictures. Maybe my noise reduction technique is bad or my sharpening skills are. But i ve integrated a significant amount of data, so I m also wondering whether i would get a better signal to noise by integrating more data, or whether I should be looking at changing settings when i capture (gain/ exposure time per frame). Where would i benefit the most?
I shoot at unity gain for the ASI1600gt across all filters - 139, with this picture at -10 but now as its getting colder i can go to -20.
the Fwhm according to DSS is 3.54 on my best frame and i exclude everything after 4.0
My guiding is giving me an average readout of 0.43 considering I am using an OAG the FWHM of the guidescope is also the same sitting at an average of 4.0.
With narrowband imaging I had hoped to achieve better results, when i look at my OSC result for 3 hours integration I m getting a better picture IMO, sure its got its flaws but the signal to noise is much more satisfying. Orion is also much lower to the horizon in comparison to the pacman but the pixel size is identicle allbeit a larger FOV. Maybe i should spend an evening on it with my OSC and see what i can get.
Please do not be too disappointed, I looked at it now in full resolution and there is a lot in there that you can be happy about! And I liked your answer what you want to achieve! I copied your full resolution image into my viewer and I am actually not as critical about the noise, it looks fairly good. And ... a complete noiseless image is sometimes looking very artificial, and there are quite a few here on Astrobin that do not favor this at all.
Also good information about your setup and what you are using. And since you have the VERY same telescope I might be of help, although ... I am not the TP or IOTD gatherer like others here.
I used with the ASI1600 usually a gain of 200 with offset 30, I liked that most. Some people go even up to 300/50. I tried that once and was not SUCH a fan of it, but maybe I did not give it enough time (all for narrow band that is). Being cooler is always better in general, so go for it when it is getting colder 😊.
My FWHM is usually pretty close to yours, I know ... people say that this is not good enough, but one can do something about it with processing, hence I think that this is ok.
With my recent image I actually did almost the same that you did (same target:
https://www.astrobin.com/cst4xu/), comparing with a wonderful extraordinary image (see version C and
https://www.astrobin.com/l8tmba/), but I knew that this would be impossible to achieve. So what is the main difference? Definitely sky conditions! Maybe more FL, but then the FoV is too small. Definitely processing skills, the top notch imagers here on Astrobin have many many years of experience. I can see that for myself, I tried more and more and more and I believe I am getting better.
Coming back to your image! What did I not like (and believe me, I have the same list for my image)???? And please don't forget, this is a personal opinion and not a general one, others might see it much different.
The first thing that popped up were the stars: they do have a red ring around them, I think all of them. This gives the whole image a red "noise", beside that the stars do not look natural. The size of the stars are a tick too large, I would try to reduce them (there are multiple techniques in processing, and no ... star reduction on the final image is not the best answer, I usually combine star images with starless images a lot). And then maybe the most subjective opinion: I am not a fan of exaggerated color, I would have tamed it definitely down. Also ... a lot of people do not like any green in the images (personally I like it sometimes, so I am not a 100% opponent of it), so the inner core is "not blue enough". Maybe I would play around with some sharpening tools, that would make the filaments more detailed, but not overdoing it, if your data do not give it, then do not do it.
Ok, sorry for the long response, but I thought your reply was very honest and I read your (not necessarily needed) frustration, your image is not as bad as I think you think about it. And not every image will be a TP or at least a nomination (I did not get one either 😊, and I truly believe that it deserved one 😊, of course 😊😊).
So please PM me if you have some question about some of the techniques that can be used, I will try to give you my best answer that I have (not the best of all of the people here, but at least an ok one I believe). Keep on going Richard!
Uwe
