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Aligning stacked LRGB images into Photoshop ???


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Hi folks ...

 

I am slowly getting to grips with LRGB processing using MaximDL and Photoshop ... and it is taking time!

 

At this point I have one question which is really bugging me ....

 

When I import my individual stacked LRGB images into Photoshop how do I know if they are accurately aligned ...... and ...... if there is any misalignment how can this be put right???

 

At the moment I am only making short runs of LRGB images and I don't seem to have any trouble with misalignment ... but I am concerned that as I grow in confidence and make longer sequences, or adding extra sequences on subsequent  nights, then I must surely start to get some misalignment cropping into the system.

 

Can anybody put my mind at rest???

 

Mike

 

 

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I found this  article on the 'net last night .... it gave me some real insights into Registar and the confidence to order the full copy. "Using Registar for Aligning CCD Sub-Frames" .... the web

Hi folks ...   I am slowly getting to grips with LRGB processing using MaximDL and Photoshop ... and it is taking time!   At this point I have one question which is really bugging

You will soon find out if they are misaligned when you try to combine the colour channels as the different colours won’t line up.  I have always found Registar the best tool for lining up misalig

You will soon find out if they are misaligned when you try to combine the colour channels as the different colours won’t line up. 

I have always found Registar the best tool for lining up misaligned data especially if you also use the crop tool. 

Carole

Edited by carastro
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38 minutes ago, carastro said:

You will soon find out if they are misaligned when you try to combine the colour channels as the different colours won’t line up. 

I have always found Registar the best tool for lining up misaligned data especially if you also use the crop tool. 

Carole

Hi Carole ...

I have never used Registar or know anything about it.

Is this used to stack & align (and crop if needed) LRGB images instead of MaximDL? ...... or after Maxim? .... before putting the files into Photoshop?

Mike

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Registar is used purely to align/register images, not for stacking.

I believe Maxim has a registration feature as well, but when I started mono imaging I tried it and found it to be hit and miss, whereas Registar does an incredible job.  You can even load images into it that have been taken on different cameras and scopes and it will register the stars and make it line up.  Also if you want to do binning, it will re-size the images to match, I would not be without it.

The crop pad is not necessary to use but it does mean you don't have to slide the filters around in channel to lay them on top of each other.  

Your normal stacking software will line up/ rotate if necessary the images taken with the same filter, but you can;t do that with the different filters as they need to be stacked separately.  So if as you say you have taken images on a different night, there could be some rotation, especially if you have had to set up the kit from scratch each time.

Once you have all your filters stacked you need to combine them have you got to that stage yet?

This is the tutorial by Annie of Annie's actions which is the method I use, this is in photoshop.

http://www.eprisephoto.com/create-lrgb

Carole 

Edited by carastro
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As per Carole, if you can afford it Registar it's worth it for the trouble free way it aligns images every time, some very dodgy ones in my case.

Maxim and P'Shop will do it but time consuming and fiddly.

Dave

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4 hours ago, Dave S said:

I usually use the Free Transform tool in PS (ctrl T)

Dave...

Hi Dave ...

I have found it impossible to use the "Free Transform" toll in PS after the RGB files have been pasted into the channels area. Any alignments have to be done before they are put into RGB channels.

Regards

Mike

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Being a cheapskate I use AstroArt for all my stacking and post (Must get hold of PI). After making my stacks, and getting rid of any non-image stacks, clicking Align All with Translstion and Rotation will do the job. Then make an RGB stack before adding the L with LRGB Synthesis.

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What is the difference between aligning and stacking (I assume registering is aligning, which is rotating etc.)?

I'm not very good at processing (or anything else for that matter) so am trying to understand the differences so please bear with me and my tiny brain.

I have, for example, 20 NB images on NGCxxx.  I open them all in Registar, select all and click register.  Does that then rotate the individual images so that each is now effectively a new image but rotated accordingly?  What do I do then with those 20 images?  Do these then get saved as 20 "new" images and taken to, say, DSS for stacking?  I notice Registar also has a combine  feature, how and when would this be applied?

Sorry for questions but this could make life a little easier for me imaging here and Spain.

Edited by RayD
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7 minutes ago, RayD said:

What is the difference between aligning and stacking (I assume registering is aligning, which is rotating etc.)?

I'm not very good at processing (or anything else for that matter) so am trying to understand the differences so please bear with me and my tiny brain.

I have, for example, 20 NB images on NGCxxx.  I open them all in Registar, select all and click register.  Does that then rotate the individual images so that each is now effectively a new image but rotated accordingly?  What do I do then with those 20 images?  Do these then get saved as 20 "new" images and taken to, say, DSS for stacking?  I notice Registar also has a combine  feature, how and when would this be applied?

Sorry for questions but this could make life a little easier for me imaging here and Spain.

Info here

https://aurigaimaging.com

Dave

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What is the difference between aligning and stacking (I assume registering is aligning, which is rotating etc.)?

I'm not very good at processing (or anything else for that matter) so am trying to understand the differences so please bear with me and my tiny brain.

I have, for example, 20 NB images on NGCxxx.  I open them all in Registar, select all and click register.  Does that then rotate the individual images so that each is now effectively a new image but rotated accordingly?  What do I do then with those 20 images?  Do these then get saved as 20 "new" images and taken to, say, DSS for stacking?  I notice Registar also has a combine  feature, how and when would this be applied?

Sorry for questions but this could make life a little easier for me imaging here and Spain.

Have sent you an E Mail Ray.

Carole 

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You can just put your 20 images (say Ha) into DSS, select a particular image to be the reference and it will align and stack them to produce a single master Ha file. You can then load your next set of NB images (say OIII) and also load the same Ha reference image, select it as the reference but do not select it to be included in the stack. DSS will then align and stack the OIII files to produce a single master OIII file which is aligned to the HA. Repeat for SII and RGB if needed.

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What is the difference between aligning and stacking (I assume registering is aligning, which is rotating etc.)?

I'm not very good at processing (or anything else for that matter) so am trying to understand the differences so please bear with me and my tiny brain.

I have, for example, 20 NB images on NGCxxx.  I open them all in Registar, select all and click register.  Does that then rotate the individual images so that each is now effectively a new image but rotated accordingly?  What do I do then with those 20 images?  Do these then get saved as 20 "new" images and taken to, say, DSS for stacking?  I notice Registar also has a combine  feature, how and when would this be applied?

Sorry for questions but this could make life a little easier for me imaging here and Spain.

Just to clarify in laymans terms.  Stacking, is putting multiple images of the same filter on top of each other (i.e. combining the data). 

Registering is making all the stars line up.  So for instance you might have lots of Ha images and lots of Oiii images.  The Ha registration will be taken care of in the stacking process (Ha stack), also the Oiii (Oiii stack) but you can't stack the Ha stack and the Oiii stack together so they need to be registered independently.

So how do you do that, as you need software that will rotate exactly so the stars will line up?  Pixinsight I believe will do this, and there are some other softwares that will do it, but Registar is absolutely great at doing this job.  It will also re-size images taken with different cameras and scopes so that when you come to combine the different filters to get your colour etc, all the stars will sit on top of each other.

I had a Horsehead image once that I had taken with a DSLR.  Then a year or two later I got a mono camera and wanted to add Ha to the image.  When I tried to register the images using other software (can't remember which now), I could get the stars to line up on the right and middle of the image but as you got further over to the left side, the stars did not line up.  I presume this was because of slight curvature in using different Flatteners etc.  Once I discovered Registar, it stretched the image slightly so that the stars all lined up.  

HTHs.

Carole 

 

Edited by carastro
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7 minutes ago, Freddie said:

You can just put your 20 images (say Ha) into DSS, select a particular image to be the reference and it will align and stack them to produce a single master Ha file. You can then load your next set of NB images (say OIII) and also load the same Ha reference image, select it as the reference but do not select it to be included in the stack. DSS will then align and stack the OIII files to produce a single master OIII file which is aligned to the HA. Repeat for SII and RGB if needed.

Thanks Freddie that's pretty much what I have been doing so that's encouraging.  I wondered how Registar differed from what DSS already does but think I can see now (different image scales etc.).

Sorry @SlimPaling conscious of unintentionally hijacking the thread.  My apologies will carry on elsewhere as seems there are some significant differences.

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You can just put your 20 images (say Ha) into DSS, select a particular image to be the reference and it will align and stack them to produce a single master Ha file. You can then load your next set of NB images (say OIII) and also load the same Ha reference image, select it as the reference but do not select it to be included in the stack. DSS will then align and stack the OIII files to produce a single master OIII file which is aligned to the HA. Repeat for SII and RGB if needed.

I didn't know you could do that in DSS, though having said that I use Astroart these days.  Maybe it is a later version of DSS.

Carole 

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50 minutes ago, RayD said:

Thanks Freddie that's pretty much what I have been doing so that's encouraging.  I wondered how Registar differed from what DSS already does but think I can see now (different image scales etc.).

Sorry @SlimPaling conscious of unintentionally hijacking the thread.  My apologies will carry on elsewhere as seems there are some significant differences.

Hi RayD .... Don't worry about upsetting me ... this is all useful info for me as well :-)))

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42 minutes ago, carastro said:

I am sure SlimPaling will find all of this discussion useful Ray as it's all relevant.

Hi Carole ....

I have just realised that I already have Regitax6 here on my computer!!! I used it over a year ago to process some video files of Jupiter ..... I didn't realise that I could use it on small sets of CCD images !!!

I have just been reminding myself about Registax .... am I correct in thinking that a good workflow is along the lines as follows?

(1) Callibrate all LRGB files in MaximDL

(2) Align them in Registax  ....after picking a few stars manually

(3) Don't bother doing "Wavelets" in Registax

(4) Stack the files into single file for each LRGB sets in Regisatx

(3) Take the stacked files into PS .... with no more worries about all frames being aligned?

(4) Process them in PS into a single file

Have I missed anything important. ... or made any silly mistakes here????

Regards

Mike

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I think I need to have a sleep !!!!

I have mixed up "Registax" and "Registar" !!!! In my haste I thought that they are the same !!!!

Ignore my last message ..... although Registax did seem to align my subs for me but haven't got as far as importing them into PS!!!

Mike

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Hi again Carole ....

After some extensive reading since I last wrote I have now taken the plunge and purchased the full version of Registar and have been "playing with it this morning" and it looks as if I am getting somewhere.

I have been "playing" with a series of LRGB subs that I took a few nights ago of M33 ... 3 of each channel. The final image that I am getting does look better than previous efforts. All files seem to be aligning in PS at least.

I have realised that I need to take more subs of M33 as my final results so far are a bit faint and lacking in detail ... so far I have only taken 3 x 300 sec subs for each LRGB's and I am pretty certain that I need more of them to get a better final result. I am still learning!!!

So ... my modified work flow using Registar, etc. , to ensure that all files are aligned and get to a final image in Photoshop, is as follows ..... please make any comments if I am doing something wrong or unnecessary !

(1) Calibrate all LRGB files in MaximDL using the various bias, darks & flats ... and save

(2) Align and crop them in Registar  .... and save

(3) In Maxim stack these files into single LRGB subs ... and save

(4) Take the stacked files into PS .... with no more worries about all frames being aligned?

(5) Process them in PS into a single file

Have I missed anything important. ... or made any silly mistakes here????

Regards

Mike

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Looks OK, I don't use Maxim in my work flow, so I just save them in Photoshop, but if it works for you that's fine.

I don't find Registar immediately user intuitive, but you seem to have worked it out.  The crop pad will make every image sit exactly over the top of each other. 

Sometimes I don't use the crop pad and this is when I want to do a bit of "fudging" i.e. fill in a corner or so that might be missing from one of my filters so I don't have to crop the image quite so much i.e. I might steal it from a previous imaging run or something. (This would happen sometimes on multi evenings when the alignment or framing is not quite the same).  So when I import the files I have to slide the different channels around to get the stars on top of each other, but it's registered just fine.   

Oh to be able to do long imaging runs with dark and clear skies and do it all in one go and not have to wait months or years to complete an image. 

I often go back to old data and add to it and often the images have been captured with different scopes/Cameras and Registar makes this possible.  I am building up a mosiac of Antares region, and don't even have the camera I started this on any more, then some I did with a DSLR, I could not combine all this data without Registar.  

Carole 

Edited by carastro
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