Rusty on maxim dl 5 LRBG ha

[graham.hobart (Graham stevens)]

Yo!! Having got my mono camera now running have collected some LRBG and ha subs in the last two nights with good seeing.
I have forgotten as it is so long since I stacked in maxim mono with filters - is it better just to chuck it all in then calibrate all then stack all together?
Or calibrate each colour and stack each colour then colour combine?
If latter how do you add the Ha in?
Cheers for answering basic question but haven't done mono for honks and feel have some good data and don't want to cock it up.
(Awaiting CCd stack key !!!!!)
Have no idea about pix insight!!!
Cheers
Graz

[graham.hobart (Graham stevens)]

I find it hard to believe that no one uses Maxim or has an opinion on whether to stack all together or stack separately then combine?
Cmon folks!!
Is it because I am from Tassie?

[graham.hobart (Graham stevens)]

Here is another query- I was debuting my STT 8300 camera with self guiding filter wheel for several hours of 100sec exposures on M20, then the next night I followed NGC 2995 all the way across the Western sky till it went behind trees and hills.(300sec subs)
On my Trifid shots I have little in the way of what looks like field rotation. But the latter NGC is almost impossible to stack in CCDSTACK as there is quite marked rotation on all the later frames.
I noted my mount had moved afterwards and being as I was self guiding on axis or very near to (so not diff flexion), is this anomaly explained by poor Polar Alignment which was acceptable higher up in the sky and with shorter subs but with the 300sec lower NGC 2995 ones, became so bad it has rendered my almost four hours of subs unusable even with the rotate and stack command in manual registration menu?
I hope this is correct so I can fix it !!

[Octane (Humayun)]

When I used MaxIm DL for stacking, I would load a folder with all my images and let it sort them out.

I would do the combine separately, though, after aligning my colour sums against the luminance sum.

H

[jase (Jason)]

Graz, calibrate each of the filtered subs. Do all L, R, G, B with the respective dark, bias and flat masters.

Only try to register the subs once. The more you align/register, the greater the risk you lose resolution especially if you are using bi-cubic resampling or other algorithms that substitute or shift pixels. Its likely not a problem for RGB data, but definitely your luminance be it clear, ha, or unfiltered data only register once. Get into the habit of only registering once and stick to it. Some prefer to build the RGB first and then align to the luminance.

To do this, register and stack your luminance and save as fits to create the master. Then for the other filtered data such as R,G,B, register the subs against the luminance master. Once they are registered, you can then stack them to produce respective R,G,B filtered masters. Note that you may find that the red filtered data can sometimes be better to register data against as stars appear tighter.

Rarely would I use MaximDL or CCDstack to do an LRGB combine. There is simply not enough flexibility doing it that way. I typically use photoshop to combine luminance with the RGB. What I will do is use MaximDL or CCDStack for Ha+R combines or base RGB combines but never LRGB or HARGB. The power of photoshop layers is hard to beat when adding luminance. This is a complete different discussion.

MaximDL for data acquisition. CCDStack for the grunt work in processing but I do shift data in and out of different tools to reach the desired goal. Shifting data out of PixInsight then into CCDStack is easy with pixel math. You'll find the image is completely dark once opened in CCDStack, but once you multiply by 130,000 counts, the image is restored to normal ADU levels and you can continue on from where you left off.

Its not what you use, but how you use it that counts.

[graham.hobart (Graham stevens)]

thanks chaps- so just to clarify...

calibrate each separate L.R.G.B subs and save as calibrated subs in separate file.

Register and stack calibrated lum to build lum master file
Use this master lum file as a reference to register each coloured filter to build a registered RGB master file (one each of RGB)

Should leave me with a calibrated registered master of Lum, R, G, and B (four files)

then do the colour combine...either in Maxim or CCDSTACK (not to au fait with PS!)

(DO I add the Ha into the Red subs?)
\
Thanks again- really don't want to cock this up as I am gathering what looks to me to be good data finally with the STT8300
Graz