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First bash at a galaxy - M33

Bizibilder

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Bizibilder

Bizibilder

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Last night I managed a long session (for me) and collected 50 x 2min subs (unguided) of M33 (Plus 20 darks and 30 flats - lantern reflected into scope from a white t shirt). First job was to discard 26 of the subs for trailing and a few "double stars" (how do they happen?), then into DSS with no further processing (kept getting out of memory until I switched off 2x drizzle!).

Anyway into PS CS5 and a play with levels and curves. I hope I've not overdone it this time! I reckon that I will need a LOT more subs to end up with a decent image and there does not seem to be any colour present at all (unmodded canon 1000D)?

Would I be better off taking 1 min subs for this sort of thing or should I stick to 2 mins?

All comments and suggestions greatfully received!

post-17157-133877501021_thumb.jpg

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Tim

Tim

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Cracking start!! Get 2 mins if you can. The double stars are usually periodic error or a physical knock/tap/wind movement.

What settings did you use for the camera in DSS? There'll be colour in there somewhere :)

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Tim

Tim

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If you use the file that DSS lets you adjust and then save it you will need to up the saturation to about 20%, but try using the 32bit autosave file it gives you.

You will need to convert it to 16 bit in CS5 before you start to work with it, but all the colour will be there :)

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ollypenrice

ollypenrice

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That really is good, and will be even better if you liberate the colour. Don't drop to a minute in my view.

The 'double star' effect can be backlash, the mount resting on different sides of the mesh. Being a little out of balance, east heavy and camera heavy, usually helps.

Olly

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Bizibilder

Bizibilder

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I've gone back to the autosave.tiff file from DSS and "added" 20% saturation - YUK, far too much - So I went for 12% after fiddling around for a while. Put that into PS and tried to process as I had for the original. I'm not so sure that I have got it right or that this is an improvement! Anyway - comments please.

I'm off to take a few more subs as it seems to be clear at the moment.

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dlp

dlp

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Oh crikey, what didn't I do (or try should I say as I'm no expert). I think it boiled down to duping layer, some contrast improvement on the core (with a mask), a bit of hue adjustment then playing with blend modes/layer opacity 'til I settled on overlay at about 40%. That put the blacks fairly near black but not quite (about 20 20 20 I think), and helped lift the core a bit more. Surprised a jpg didn't fall apart, but didn't end up with any combing in the histogram remarkably.

Hope you don't mind - desperate to get some more experience doing this stuff for when I can take a decent image myself...

David

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dlp

dlp

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I think I've gone about as far as I can with my limited knowledge too! I'll leave the coup de grace to the experts.

Photoshop is brilliant and would get my vote for the best piece of software ever written - it's well worth learning and IMHO is a lot easier than say PixInsight, which is fearful. Thank you Thomas Knoll.

David

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Bizibilder

Bizibilder

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NOW WITH ADDED PHOTONS!!

The attached is a new stack over two nights (thanks to martin_h for how to do this using groups in DSS!) giving a total of 58 x 2 min subs unguided. On the first night I rejected 26 out of 51 subs, second night 27 out of 60 were rejects). (split: 24subs +20darks and 30flats ::: 34subs +20darks and 30flats) stackes in DSS (with no processing) and then into PS CS5 for levels and curves. There still seems to be little colour - though I am using an unmodded 1000D so reds will be weak. Nearly forgot - ISO 800.

As always comments please!

post-17157-133877501612_thumb.jpg

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michael.h.f.wilkinson

michael.h.f.wilkinson

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NOW WITH ADDED PHOTONS!!

The attached is a new stack over two nights (thanks to martin_h for how to do this using groups in DSS!) giving a total of 58 x 2 min subs unguided. On the first night I rejected 26 out of 51 subs, second night 27 out of 60 were rejects). (split: 24subs +20darks and 30flats ::: 34subs +20darks and 30flats) stackes in DSS (with no processing) and then into PS CS5 for levels and curves. There still seems to be little colour - though I am using an unmodded 1000D so reds will be weak. Nearly forgot - ISO 800.

As always comments please!

I do not think I have ever seen a shot of M33 with a great deal of colour. You could try fiddling with saturation, but I don't personally like that very much. Great improvement by the way!

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MartinB

MartinB

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Fantastic work, the detail within the galaxy is very high class. You've got great data there, no need to push it til the pips squeak and I think it would look nicer if you just held back a little on the histogram stretch. Otherwise it's a corker.

I don't use DSS so can't help you on the colour, only to say this looks like a mono image but I'm sure the colour data is there somewhere. Remember, when you do find it the colour will be weak water colour rather than oils, you will need to do some careful processing to enhance the colour without introducing noise.

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