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M42 to IC434


Adreneline

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This is R, G, B, Ha, OIII and SII all taken with a ZWO-ASI1600MM-Pro fitted to a Canon 200mm f2.8 lens.

The R, G and B were all 10s and 30s combined in Photoshop. The NB was all 30s, 60s and 120s, again layered in Photoshop.

This is essentially RGB combined with HOS, pre-processed in APP, post-processed in PI and combined in PS.

Orion-HOS-v3.thumb.png.a9de91a3c83965bbb208defc234de676.png

Thanks for looking.

Adrian

Edited by Adreneline
Forgot the image!
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Thanks for the kind comments @assouptro, @alan potts and @geordie85.

I took this image over two weeks ago and have been messing around with the processing ever since! Despite having everything thrown at it (filters and software) I still seem to have successfully lost all the star colours :( 

More cloudy nights forecast so perhaps I'll have another bash.

Thanks again.

Adrian

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45 minutes ago, alan potts said:

star-colour preserving stretch

Hi Alan,

Thanks Alan - I'll go in search and see what I can find.

My basic RGB subs don't seem to contain that much colour - probably because they are so short (10s and 30s). I tried using ArcsinhStretch in PI and that introduces lots of colour but the stars all look a bit untidy and ill-defined. By the time I've restored the star shapes most of the colour seems to have evaporated away again so that when I come to layer them into the NB image it is very hard to see any real difference. I've also used basic HistogramStretch on the RGB image but again the colour is not really there and by the time it starts to show the stars are all getting a bit bloated.

It's all a bit of a challenge. I think I favour little stars with a lack of colour to bloated stars with colour.

Adrian

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1 hour ago, Adreneline said:

Hi Alan,

Thanks Alan - I'll go in search and see what I can find.

My basic RGB subs don't seem to contain that much colour - probably because they are so short (10s and 30s). I tried using ArcsinhStretch in PI and that introduces lots of colour but the stars all look a bit untidy and ill-defined. By the time I've restored the star shapes most of the colour seems to have evaporated away again so that when I come to layer them into the NB image it is very hard to see any real difference. I've also used basic HistogramStretch on the RGB image but again the colour is not really there and by the time it starts to show the stars are all getting a bit bloated.

It's all a bit of a challenge. I think I favour little stars with a lack of colour to bloated stars with colour.

Adrian

I actually set about trying to invent my own way of reducing stars in PS and got an amazing amount of colour into them, didn't reduce them one bit. Sadly I didn't write down what I did and forgot how i managed it in the first place. I personally think the image you took is lovely, and as said by others framed beautifully.  I can't get this wide field with a scope but I always have a battle with Alnitak.

Alan

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10 minutes ago, geordie85 said:

For star colour I usually use the select highlights tool early on, copy and paste that into a blank clipboard, increase the colour then paste it back I to the original as a colour layer blended at 50%

That sounds worth a look at - thanks very much.

Adrian

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Excellent image - like it enormously,  Probably try similar soon if/when we get some clear nights.  What gain settings did you use on the ASI1600MM?  I'm trying to sort out best settings.  I have 200mm f4 Asahi Super Takumar lenses I plan to try.  Bit slower that your 200mm but we'll see.  Might be better with 135mm f2.5 but single imaging rig.  TBH I wouldn't have thought of using RGB subs.

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35 minutes ago, Gina said:

Excellent image - like it enormously,  Probably try similar soon if/when we get some clear nights.  What gain settings did you use on the ASI1600MM?  I'm trying to sort out best settings.  I have 200mm f4 Asahi Super Takumar lenses I plan to try.  Bit slower that your 200mm but we'll see.  Might be better with 135mm f2.5 but single imaging rig.  TBH I wouldn't have thought of using RGB subs.

Thank you Gina.

I always use a gain of 139 and an offset of 56. The LP levels here are not conducive to pushing the gain any further. I've tried 200 gain and not really noticed any difference in the end result. Sticking to 139 and 50 makes life simpler with calibration frames.

The Canon 200mm is really very good and I feel better than the Samyang 135mm in terms of star shapes in the extremities of the image. Definitely worth having a go with your f4 I would say.

Adrian

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15 minutes ago, lux eterna said:

I like the natural look you get with that gentle processing.

Thanks Ragnar. Space might be spectacular but I personally don't believe it is garish.

12 minutes ago, Ruud said:

It's like a family portrait with everyone gathered in the same frame like this.

Thank you. A family portrait - just what we all need at Christmas :)

Thanks for the kind comments.

Adrian

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