Creating a LRGB image help

[Nigel G]

Hi all.

I have been given a set of Fits to try LRGB & NB combinations with.

I have R,G,B,Ha,OIII & SII to play with.

First snag, I load the 3 narrowband fits as SII- red, Ha- green and OIII- blue in StarTools LRGB, they are same size but not matching frame, slightly different positions, so do not line up.

How do I align the frames to match each other, I'm using Startools for the image combining and processing.

Any advice would be great.

Cheers

Nige.

[Knight of Clear Skies]

Hi, I had exactly the same problem with aligning my M31 channels, I found a couple posts on here with a solution. I restacked each channel using the same lum sub as a reference frame (unticked, so it did not add it to the stack). I had to select 'standard' mode rather than 'intersection' or 'mosaic'. This gave me three colour channels with the same size and alignment as the lum stack, which I could then load into StarTools.

Alternatively, you could nudge the channels around in photoshop with the arrow keys, this should work OK as long as there isn't any rotation between the channels. Selecting a different blending mode temporarily may help with spotting any misalignment.

[Nigel G]

4 minutes ago, Knight of Clear Skies said:

Hi, I had exactly the same problem with aligning my M31 channels, I found a couple posts on here with a solution. I restacked each channel using the same lum sub as a reference frame (unticked, so it did not add it to the stack). I had to select 'normal' rather than 'intersection' or 'mosaic'. This gave me three colour channels with the same size and alignment as the lum stack, which I could then load into StarTools.

Alternatively, you could nudge the channels around in photoshop with the arrow keys, this should work OK as long as there isn't any rotation between the channels. Selecting a different blending mode temporarily may help with spotting any misalignment.

Thanks for your reply.

I only have the already stacked fits files, so restacking is not an option for me, and PS will not open fits files, will I need to convert to a tiff ?

I was wondering if DSS could do it for me after stacking with fits files.

Nige.

[Davey-T]

DSS gives you the option to save as 16bit Tiff that will open in PS.

Dave

[red dwalf]

photoshop will open fits files with the proper plug in, i do it all the time now.

http://hubblesource.stsci.edu/sources/toolbox/entry/fits_liberator/

[Freddie]

You can just pop the FITs into DSS and align them without having to restack. Can't remember how off the top of my head as I haven't used DSS for a while now but I'm sure a quick search would point you in the right direction.

[Craney]

Hi Nigel,

I have just been experimenting with some Narrowband images as well and have had the same problems. I used the advice given above with regard to DSS and using a reference frame that ultimately does not get stacked and it worked to an extent.    The problem I had was my 0iii and Lum were taken with 2" screw in filters, but my H-a was with an EOS clip in the camera, so I had a distortion as well as a slight rotation with possible skewing as well.....  blimey !!

I have had about 3 nights trying to wrangle out an aligned set of images.....  the breakthrough came with using a 'lens correction' function in Photoshop together with some 'alignment' wizardry in the editing of the layers.....   I'm a bit of an idiot when it comes to this type of thing, but I surprised myself with this !! 

Here is a sample output...

So keep plugging away, and good luck.

 

Sean

[Nigel G]

Thanks for your reply's.

Still had no joy.

I tried cropping with StarTools using a star as a start point, but just can't get it identical, a few pixels out.

I have PS CS2 but really don't know what I'm doing, having only used it for mosaic's and final touch ups as I use ST for my processing.

I will be searching DSS for the answer when I get home from work.

Cheers

Nige.

[ollypenrice]

The Ultimate Weapon is Registar. It's quite expensive but it's infallible. It can also combine images at different pixel scales, with different field curvature, etc etc. It's a time saver which I use several times on every image I do.

Olly

[Nigel G]

No joy yet.

Thanks for the link to registar Olly, it looks a great program, but as these files are not mine and I don't have a mono camera yet I will hold fire with that  

Looked through DSS files and cannot find any reference to aligning without stacking, fits files. ( maybe I missed something )

I don't like walking away from unfinished business but I'm just about ready to give up with this as its not my data, just a bit of practice to pre owning a mono camera. A shame but to much time spent trying and searching.

Thanks for your input everyone.

Nige.

[Freddie]

About half way down this thread shows you what you need.

 

[Nigel G]

16 minutes ago, Freddie said:

About half way down this thread shows you what you need.

 

Thanks Freddie,  that looks like what I have been searching for. 

I'll give it a go tomorrow. 

Nige.

[Nigel G]

Done  

Thanks for your help, easy when you know how.

I followed the link Freddie posted.

Cheers all

Nige.

[Freddie]

Glad it worked for you. I use AA6 these days so haven't used DSS for a while. I knew it could do it, just couldn't remember how!!