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kingboya

First light Atik 314L on ED80 (eventually)!

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Also, I noticed when binning 2x2, that the RGB images were smaller than the L at 1x1. I scaled up the RGB to the same size as the L, or should I scale down the L to the RBG?

When you bin 2x2 pixel are grouped into 4 pixels(2vertical x2 horizontal) to make one super pixel thus increasing its sensitivity so to speak but this halves the resolution thus the smaller size.When processing you should resize the RGB to that of the luminance

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Very well done, that second process really is fantastic, its a very steap learning curve but I think your ahead of it!:)

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But theres nothing like experimentation as long as you keep original data

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When you bin 2x2 pixel are grouped into 4 pixels(2vertical x2 horizontal) to make one super pixel thus increasing its sensitivity so to speak but this halves the resolution thus the smaller size.When processing you should resize the RGB to that of the luminance

Thanks for that, explains a lot! :)

Very well done, that second process really is fantastic, its a very steap learning curve but I think your ahead of it! :)

Thank you. I am really enjoying the whole process of imaging, and I am just happy I have some data to play around with!

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That's brilliant - great processing job - well done :)

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Also, I noticed when binning 2x2, that the RGB images were smaller than the L at 1x1. I scaled up the RGB to the same size as the L, or should I scale down the L to the RBG?

I'm guessing scale up to luminance so as not to lose resolution.

The only thing I haven't got my head round fully, is when to resize. I think it should be done once it has been stacked into the individual colour frame.

Typed by me on my fone, using fumms... Excuse eny speling errurs.

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I'm guessing scale up to luminance so as not to lose resolution.

The only thing I haven't got my head round fully, is when to resize. I think it should be done once it has been stacked into the individual colour frame.

Typed by me on my fone, using fumms... Excuse eny speling errurs.

I combine the rgb and then resize it to match the luminance

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I'm guessing scale up to luminance so as not to lose resolution.

The only thing I haven't got my head round fully, is when to resize. I think it should be done once it has been stacked into the individual colour frame.

Typed by me on my fone, using fumms... Excuse eny speling errurs.

I resized my RGB in AA5 and then aligned all, including my previous luminance image. Then I input the RGB into the channels in PS and added luminance in. My RGB is not too good at all and is washed out by the luminance it seems. I will no longer bin the RGB, but instead just get less of it if that makes sense :-)

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I combine the rgb and then resize it to match the luminance

Do you combine in AA5 then import into PS?

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I wouldn't combine L and RGB till both are processed. The processsing priorities are totally contradictory. In L you want sharpness, contrast, detail, faint stuff highly stretched. In RGB you want strong colour and low noise but detail is not important. To reply to an earlier question, yes 120 minutes L would be OK with 40 mins per colour.

I would resize binned RGB before processing it because you need to see the noise limit clearly when you stretch.

When you find your L washes out the RGB here are two possibilities that I know of;

1) Convert RGB to Lab colour mode and in channels a and b simply use the standard contrast tool (the only time you'll every use this numpty device!!!!) and whack it up to 30 or so then recombine and revert to RGB mode. This improves colour saturation at a low cost in terms of noise.

2) Apply your L layer to the RGB at a low opacity. Reduce the noise (Gaussian Blur, Reduce Noise, Despeckle, whatever works), boost saturation and then re-apply the L layer to this again at a low opacity. Repeat this process till you can get the L to work at full opacity. Be patient and this is remarkably effective.

The reason I don't like binning colour is that I like to use RGB only for the field stars. There are various ways to avoid applying the L layer to the stars in order to have them smaller and more colourful without being over exposed in the core. However, this means you have to have nice RGB stars to start with and if you bin them this won't be the case. (In this collaborative M31 the galaxy had about 47 hours of data pooled by four imagers but the field stars have just an hour per channel RGB. http://ollypenrice.s...TEC CORE-X3.jpg ) It must be confessed that the stars in the very outer halo are a little larger than the field stars but I thought this a price worth paying.

If you obtained colour for this M51 unbinned and have the guiding nailed you would be able to forget the slight trailing in the original L layer by applying the L only to the galaxies...

Olly

Edited by ollypenrice
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@Olly - do you use shorter RGB subs for the stars then increase RGB sub length to capture more colour in the target or do you just do a mild or masked stretch for the stars? If I expose too long in RGB I clip my stars quite a bit.

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@Olly - do you use shorter RGB subs for the stars then increase RGB sub length to capture more colour in the target or do you just do a mild or masked stretch for the stars? If I expose too long in RGB I clip my stars quite a bit.

Noting the effect on star colour of long exposures in RGB is on my 'to do' list but I don't think I get too much white clipping in long RGB subs. I can't give you a decent answer yet, I'm afraid. I haven't yet taken short star subs, though.

Olly

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Do you combine in AA5 then import into PS?

I calibrate all the subs in nebulosity(although AA5 is ok for this).I then align and stack each channel seperately(LRGB) in AA5.I then load the stacked R G and B master frames and align all before using the trichromy tool to combine.it is important to align all three first before using the trichromy tool as the trichromy tool will only align the red and blue channel.Then I follow Ollys post aligning but not combining the rgb and luminious and continue the processing in cs6.I use method 2 adding the luminous in stages

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Here is my final go at processing the data for my first LRGB image. Using the method of blending the Luminance layer a few times, I am quite pleased with this final image, considering the RGB data. Red 8x300, Blue 11x300 and Green 12x300 all binned 2x2 and using the original reprocessed L image. It is far from perfect, but I am leaving this image here I think. I want to get more data sometime (soon) on this target. I love M51, but I won't bin it the next time!

Thank you all for your help in this thread for this CCD newbie, but I actually feel I have come a long way in this process already, and am yearning for more data now to play with. :)

post-19531-0-76300800-1365608442_thumb.p

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thats a great improvement.

one thing i find is its very handy reading around the different threads like this one, its surprising what you actually read and learn,mr penrice is certainly a wealth of knowledge :icon_salut: thats why i've marked this thread, a few handy processing tips there to try myself.

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thats a great improvement.

one thing i find is its very handy reading around the different threads like this one, its surprising what you actually read and learn,mr penrice is certainly a wealth of knowledge :icon_salut: thats why i've marked this thread, a few handy processing tips there to try myself.

I totally agree that Mr Penrice and many others here are very happy to share their knowledge and experience so that we can all improve our images. This is a great thread and one that I will keep coming back to for information. :p

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Thats looking better the detail appears sharper well done

thats a great improvement.

one thing i find is its very handy reading around the different threads like this one, its surprising what you actually read and learn,mr penrice is certainly a wealth of knowledge :icon_salut: thats why i've marked this thread, a few handy processing tips there to try myself.

Yes I agree Olly has provided me with plenty of advice as have others

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Definately one for a rainy evening, i'll be having a go at reprocessing a few of mine.

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