Omega Centauri - NGC5139

[prova]

total noob to astrophotography but slowly getting there as this is about my 4th outing with my DSLR connected via prime focus.

any useful tips would be appreciated :)

[g__day]

The stars are nice and tight - a bit faint and a shade green. So well done.

Advice - processing - Photshop CS or MaximDL - levels and curves to boost the signal - maybe go a tad longer on duration but don't blow out the core and check colour levels of your camera against a white reference star (G2V) (some in the Southern Cross) i.e.

http://www.astropix.com/HTML/I_ASTROP/CUSTOMWB.HTM

With only basic processing - it looks like this

[JohnG]

Hi

There is a lot of information in your shot, I hope you don't mind but I ran it through PS CS2 and did a few basic steps.......

There was an awfull lot of green in the shot but I managed to get a lot of it out for you, a few iterations in Levels and Curves did the trick with a bit of colour manipulating.

Don't let this put you off, it is a long learning curve and you get better with practice and by asking questions. :thumbsup:

Cheers

[prova]

thanks!

when 'processing in photoshop' is mentioned, what does that actually mean?
is it just adjustments made or is there a script run over the image?

[JohnG]

There are some tools that run script's but basically it is a matter of adjusting the sliders to get the effect you require.

Here are a couple of tutorial's, at the bottom of the page.

They will explain better than I can :).

http://www.ip4ap.com/IP4AP_Tutorials_Video.html

Cheers

[prova]

Thanks John

[JohnG]

Just one thing, I asume that the photo was taken as a JPEG, check your White Balance on your camera, you should have it set on Daylight, from the green tinge, it looks like it is set to Tungsten or something other than Daylight, just a thought......disregard if you shot RAW's, white balance dosen't matter then.

Usually with Omega, I do 60 second subs at ISO 800, RAW setting, then combine the shots with appropriate Darks and Flats.

See here: http://www.pbase.com/takman2/image/70821267

Cheers

[prova]

they are JPEG and I am pretty sure I did set it to Daylight, however will double check.

Is there any visual advantage in taken them with RAW?

also, what are your recommended settings for M42 as most of mine have come out rubbish ..

thanks again John

[JohnG]

Hi

As you are just starting out I would suggest that you stick with JPEG for a while, learn how to use your scope and camera gear. The main thing with RAW's is that it preserves the original data from the camera and saves in high bit depth, this in turn allows you to get the most out of your shots. That said, you will need something like ImagesPlus or a similar program to convert and calibrate the shots and turn them into TIF's.

Unfortunately, a lot of beginners want to shoot M42, there is a lot of variation in colour and brightness, that in turn plays havoc with any photo, my suggestion would be to try a number of different length shots, starting from, say 5 seconds up to maybe 60 seconds or more then combine and layer the shots so as to eliminate any burning out of the core, not easy if you have not done it before.

Cheers

[prova]

thanks ill give it a go!

[EzyStyles]

Hi Mark, answering your pm, huge improvement from your previous image! You definitely got focus/tracking right now you need to work on your colour balance as it looks abit too green. easiest way is in ps2 when adjusting levels, click the middle button and then click in a black background. it should auto balance it :)

ps. im one of the guilty ones shooting all my images in jpeg :P