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Andromeda wide.


ollypenrice

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I had an Andromeda squeezed onto the chip diagonally but it had a fair few mistakes in it and was short of living space. Guest Ian Bird was up for catching a two panel mosaic in LRGB and then blending in the old data for depth, so that's what we did.

Old data, 11.5 hours.

New data, an hour each of LRGB per panel. Total 19.5 hours. Ha is still to come. (We have YOUR cloud here, thank you very much!! :grin:)

Our Tak FSQ85ED at F3.9/328mm. Old data on our EM200, new data on Ian's Celestron CGEM DX.

Preprocessing AstroArt 5.0. Post processing, Registar, Pixinsight and Photoshop CS3.

Olly and Ian.

Bigger; http://ollypenrice.s...qc88vQ&lb=1&s=O

M31LRGB-2-PANEL-WEB-XL.jpg

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The colour is especially good, M31 with LRGB is normally pretty weak in colours, they don't just jump out at you! Olly, you'll have to give us some tips on how you've teased out the colour on this lovely image - I think a lot of us would benefit from this - thanks

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The colour is especially good, M31 with LRGB is normally pretty weak in colours, they don't just jump out at you! Olly, you'll have to give us some tips on how you've teased out the colour on this lovely image - I think a lot of us would benefit from this - thanks

Thanks Martin. FIrstly there's a lot of signal in the colour channels and F3.9 makes it easier.

Even so, I looked at the RGB and thought, Yikes, not much colour! I worked very slowly using a variety of techniques to build it up. Briefly...

The RGB layer combined the old LRGB and the new RGB. This is a little like the Gendler technique in which you add a little L to the RGB, blur it, and add more L, gradually building up the brighness of the RGB and de-noising, though in my case I ran no de-noising filters on this one.

Next came one I leaned from MartinB. Into Lab colour mode and increase the contrast on a and b channels by 40 ( !!!!! :BangHead: ) Recombine and revert to RGB.

Use colour select to select the background sky, select inverse, and use Match Colour (colour intensity) and lastly plain old Saturation. I use Saturation last every time because it is a noise monster.

Guests tell me that colour is much better from our dark site than at their homes. Many come with Ha already done at home and some already have an L layer in the can as well. I've never imaged anwhere else so I can't comment.

I think the key things are lots of data (obviously) and making small steps in the processing rather than large ones.

Cheers,

Olly

Olly

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Hi

Well M31 is a stunner well processed and all that , top notch :grin::kiss:

Still do not like the centres of your bright stars , but you are bored of me saying this ,,, so won't mention it again :kiss: :kiss: :kiss: :kiss: :kiss: :kiss:

Harry

Not at all, Harry. In fact your critiques have led me into erasing L from the field stars and doing a starfield only stretch. They seem to me to have colour all the way in to the cores now but I'll certanly have another look.

Olly

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Hi

Its the transition to the core of the very bright stars , to harsh in my humble opinion :lipsrsealed:

Harry

Okeedoke, Harry, I'll have a look. I certainly agree that this was so in earlier images of mine so doubtless it's still true!

Olly

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Three stars are too bright and blue.

That's it.

I'm still knocked backwards (Swedish expression) by the colour and subtle details in this image. I've been flying over Les Granges a lot recently wondering how you were doing down there.... It seems your doing just fine.

Beautiful!

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Three stars are too bright and blue.

That's it.

I'm still knocked backwards (Swedish expression) by the colour and subtle details in this image. I've been flying over Les Granges a lot recently wondering how you were doing down there.... It seems your doing just fine.

Beautiful!

I wondered if those contrails were yours!! We're fine but lack any recent Swedish input... :grin:

Awe, I kind of liked those intense blue stars to give a bit of foreground but it looks like they'll have go!

Olly

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