M 83 Luminance and RGB seperately?

[batema (Mark)]

Hi,

I have tried to stack my LRGB images using photoshop CS3 and manually aligning the images and then with the four images aligned then I process normally. The first image is my result using this process. I don't know if this is the way to do it or if you process the Luminance to a finished product and then do the same with RGB stacked and then somehow you layer them and blend???? The second image is just my Luminance processed.

Taken with a QHY-9 through a William Optics Flt110 guided PHD and stacked DSS. Lum 5x5 Min 1x1 binning and RGB are 3 Min 2x2 binning all with darks but unfortunately no flats.

Any advice would be more than welcome.

Mark

[multiweb (Marc)]

Hi Mark, cool shot . I wouldn't use PS to align anything. It's fine for blending but alignment and data rejection needs to be done in a dedicated software IMHO like CCDStack or Maxim, IRIS, etc... There are many.

[Bolts_Tweed (Mark)]

Gday Mark

Cloudy here so heres my 2c. Yep to the RGB - quick nasty stack is fine. I process the heck out of my luminance layer to completion then copy and paste it in as a Luminance blending mode on top of the RGB. Dropping the opacity of the lum sometimes also gives pleasing results (Thx to Jase for that advice)

Sometimes a touch up is required inprocessing after flattening the image

Dont know if this answers you question

Mark Bolton

[batema (Mark)]

I am fairly confident I know what you are saying Mark so will give it a go. Yes I think I need another outlay of $$$$ Marc but I just recall I have the free version of IRIS on my laptop. Will check it out. Thanks.

Mark

[multiweb (Marc)]

Originally Posted by batema

I am fairly confident I know what you are saying Mark so will give it a go. Yes I think I need another outlay of $$$$ Marc but I just recall I have the free version of IRIS on my laptop. Will check it out. Thanks.

Mark

You don't have to spend $$$$. I think a good stacking program is a must. Otherwise you bodge good data that you took so long to capture. When you think about the time needed to get good quality subs freezing your a** off, what's a couple of hundreds on CCDStack or other to do it right.

Don't get me wrong PS is great to color balance and bring out details in your shots but there's more to calibration, registration, normalisation, data rejection and stacking than aligning a couple of subs and matching stars manually in PS.

If you want to do some reading on all this I recommend Adam Block's tutorials at caleum observatory. Needed skills well worth your learning IMHO.

[batema (Mark)]

I've been told about these programs before Marc and yes I know thtey would be good. I like the idea of putting in your data and the pressing a button.

Mark

[multiweb (Marc)]

Originally Posted by batema

I've been told about these programs before Marc and yes I know thtey would be good. I like the idea of putting in your data and the pressing a button.

Mark

That's the thing. You don't want to do that. You want to understand each step in the flow and have control of the parameters for each step. It's the only way to learn and get the most out of your data.

I can assure you that we're all getting pretty much the same raw files out of our rigs provided we reasonably take care of the fundamentals such as focus, guiding, PA etc... The rest is in the processing and understanding it. That's what makes the difference. Be wary of "blackboxes" with one button to press. You need to know how it ticks inside.