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Bolts_Tweed
19-04-2010, 09:34 PM
Gday

Another fine weekend in SE Qld - unbelievable - blew a force 10 gale at Leyburn but got some data.

Messier 83 is an reporo with shorter exposure mask from my previous post. Eta is just a quickie between gusts.

AstroPhysics EDT130, SBIG ST8300, Atrodon E Series LRGB

M83 LRGB - 160, 80, 80, 80
Eta LRGB - 20, 10, 10, 10

I cant work out the stars but - The stars behind (ok in front of) the M83 image (and the core !!!!) are built on 1 minute exosures and they still look like overexposed blobs - damn this is frustrating - they just lack the zing or pop i'm looking for - more pratice and experimenting I suppose. 30 seconds reduces them a bit but not to something approaching what i'm looking for. Tried short exposures, minimum filter, pinching and that about limits by bag of tricks.

Anyway heres my weekend.

Mark

duncan
19-04-2010, 09:51 PM
Hi Mark,
Re M83, i've seen some members talk about masking stars and i guess reinserting them at much shorter exposure.I think that's what they were on about:shrug:.
As for Eta i love it , beautiful image.
Well done on both counts.
Cheers,
Duncan:)

Bolts_Tweed
19-04-2010, 10:02 PM
Gday Duncan - Thx mate

Yeah the stars in this image (M83) are 1min subs (10 of) LRGB and the galaxy (8 min subs) is masked through the shorter image (I know someone is going to point out the colour gradient so i'll just own up now - ;))

Damn - I just looked at it and realised it isnt the MLDB image - i'll update it later.

What dumbfounds me is that the gear can resolve small dust lanes in objects like these a few pixels wide but short exposures still give blobs for stars - maybe I am being too picky but it seems that I need to improve star size (or zip or pop) and star colour before I worry about faint fuzzies. Although there is very little processing in these 1 min star images.

I cant believe I am doing this for fun. :) Makes a root canal easy.

Thx for the comments mate

Mark

duncan
19-04-2010, 10:09 PM
Mark maybe you can reduce the gain,gamma and brightness on the short exposure shots to get them more pin point?
I don't know the answer as i haven't been there. Just a thought.
Cheers:shrug:

multiweb
19-04-2010, 11:21 PM
Try to lower the black point in your raws and up the white point even if the image looks washed out. Save as a scaled TIFF. Then narrow down the levels and curves in PS while keeping an eye on your histograms and stars.