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ZeroID
20-10-2017, 07:15 PM
A question for you experts in the mono camera image processing department.

I have finally acquired a bunch of my own LRGB images AND managed to figure out the process of stacking, aligning and then converting to RGB Channels and finally produced a proper image. I am not going to put it up here for comment because it is of nothing in particular, just a proof of the whole process. But I have a question. :question:

I also took and stacked some Luminance Frames with the RGB pics. How\where does one include that into the RGB channels ?

I also took Ha but there was nothing in the region to be of any use. I gather that gets added to the Red channel. At what point does that all happen.

I am impressed with the resolution and sensitivity of the camera but boy, have I got a lot to learn !!

barx1963
21-10-2017, 12:33 PM
I have found this video as a good starting point for LRGB processing in Photoshop https://www.youtube.com/watch?v=b9ePip4rdsI&t=1046s
I am sure there are many better/more advanced ways of doing this but I have been overall happy with results from following this.
The other thing I have found helpful is using Pixinsight for calibration, registration and stacking to get my masters before saving as .tif files and using PS. I have found the results to be superior generally than using DSS. I purchased the eBook version of Warren Kellers Pixinsight book to help guide me through those early steps. Generally I have found PS to be easier and produces better results for minimal effort than PI once you have your masters sorted.

Malcolm

glend
21-10-2017, 02:53 PM
My usual way of adding a Luminance layer to an image in Photoshop, it to do a Combine on the RGB layers, then add a new layer on top of that which you identify as a Luminance layer and you can choose Soft light, or Luminance instead of the usual Screen type. You can adjust the Opacity slider to determine the impact of the Luminance. I find generally around 17-20% is plenty of Opacity. It is also possible to use Ha as a Luminance layer in this same way in narrowband images, or to add Ha to Red layer in RGB. In targets like NGC55, which has Ha nodules, it is effective. On narrowband images I always use an uncoloured Ha layer on the Combined, as a Luminance layer, again putting that on top of your SHO, or HSO, etc Combined pallet layers but dialing back the Ha luminance layer opacity to improve the contrast.
There are a large number of Utube tutorials on how to create a Photoshop layered astro image, which take you step by step through the process. Ken Crawford's are among the best.


http://www.imagingdeepsky.com/Presentations.html

I recommend the Clipped Mask tutorial as it shows the way in which he applies Luminance and color correction.

BTW, I do not use PI for anything, it is an un-necesssary expense. DSS does all the Calibration, Registration and Stacking just fine, and outputs as a TIFF if you set it up that way.

Octane
21-10-2017, 03:53 PM
Glen,

This might hold true for you. However, there are those of us who make extensive use of advanced tools that PixInsight offers that other tools, don't. One such example is the fine-grained noise reduction that MultiscaleMedianTransform provides. There is so much more to image processing than simple calibration, registration and stacking. To get the most out of your data, you use the tools available to you. And, I don't mean introducing artificial details through heavy deconvolution.

H

glend
21-10-2017, 04:13 PM
An expected reaction, everyone is entitled to their opinion and choice of tools, to use what suits them without being made to feel inadequate for not embracing your approach.;)

Octane
21-10-2017, 04:27 PM
Of course everyone's entitled to their opinions. However, you stated that PixInsight is an unnecessary expense. I am far from a fanboy, but, I qualified my statement with one example as to why in my opinion it is worth it. Bear in mind that I didn't pay for my copy; it was gifted to me at the AAIC conference in 2011. I wouldn't hesitate to pay for it, though, given what it can do.

You were never bullied for your image (the narrowband Prawn Nebula from memory) -- you were given encouragement to try something different. I think that you may have mistaken mine, and other people's intentions on commenting on your image.

H

RickS
21-10-2017, 04:28 PM
Hear, hear! It is childish to take personal affront just because somebody likes something you don't.

barx1963
21-10-2017, 05:24 PM
I think I will clarify my comments earlier. I found DSS was not producing results I wanted when used for RGB or NB work on a mono camera. Just couldn't get it to register all the subs well so when I combined them the star colours didn't line up. Despite asking a few times on this forum and others, couldn't get a clear answer so I tried it in PI, bingo! Works very well simply following the guidelines in Warrens book. Having an excellent program with good documentation in that book has been a godsend for me after trying to use several programs such as Images Plus, Nebulosity etc with their disjointed online tutorials that make it really hard to simply follow a procedure to get a result. Ended up with masters that I could import into PS and then process. Since then I have done further PI processing of the masters, mainly using Multi Scale Linear Transform to do some noise reduction. I am still struggling to use PI to get good results beyond that, so I am then saving the .tifs and using PS.
Not saying that is the best way, but for a raw beginner, I get results that I am pleased with.

Malcolm
PS: And PI is not that expensive when you have $15000 of gear sitting in the back yard, a few extra $$ to get the images processed is not really a big deal IMHO:D

ZeroID
21-10-2017, 05:36 PM
Blimey !
Didn't mean to start a processing war...

There is enough information in Malcolm's and Glens posts to give me some clues. I've only just started this 'mono' journey and I'm working with software I am familiar with to understand the process before I consider making any changes to the tools I might use in the future.

Cheers all ..

sil
25-10-2017, 09:50 AM
:thumbsup:

I think the real problem is people not challenging themselves enough to learn the tools they have and develope new skills to get the most from their data. I use PI primarily because it does offer so much to let me experiment and learn ways to improve my images. DSS I find too simple and frankly to me useless for anything. I do see amazing images being produced from DSS as some users have learnt to use it far beyond where my skill took me. I am seeing a lot of potential in the new APP especially for DSS users who want a simple hand holding experience but are willing to explore too, its still not there yet but its promising. The software doesn't matter, it won't magic your images for you, YOU still have to use the software and you can use PI as a simple as you want, a one click solution if you want. But it offers so very much more to those willing to learn and explore.