First try at RGB & Registar

[Nathan_Pembs]

Recently bought some filters and last night was the first time to try them out. Also downloaded the trial of Registar to combine the separate channels.

The result I got from a quick go was this below, obviously something isn't lining up lol Is it bad guiding? Or has the ccd rotated when I manually changed the filters?

Any help would be great appreciated

[msh1]

your blue and red channels are defiantly out of alignment, you could manually do it in photoshop or better yet nebulosity

mark

[Freddie]

Don't use it myself, but isn't the whole point of registar that it will align the various images? I therefore think something has gone wrong with your use of registar. Sorry can't help as I have never used it.

[Jessun]

No matter how you rotate the CCD - as you suggested - or even if you change scopes mid session, Registar will sort it out.

It is not entirely straight forward though and a bit of experimentation is called for to understand it.

I personally do the following:

- Open all stacks or images you wish to combine - make sure orientation is the same.

- Choose one as the 'main one' - perhaps the one in which you think you framed a target best. (No action in the program, just a decision)

- Click on one of the other images to make it active.

- Click the button register (or F2) - a dialoge window comes up and asks which other frame you want to register it to. Pick the one you have chosen as 'main one' and select this in the 'to this image reference group'. Click 'Register' in that same window. A few seconds will lapse and Registar will create a new window with the two images overlaid.

- Click 'Operations', 'Crop/Pad image' (or just hit F8) - another dialogue comes up - just click the 'match' - and OK will be available to click on. So click OK. Save the resulting image with a clever name - or just leave it with the name suggested - pretty much the original image name as prefix and 'CP' as suffix (crop and pad).

- Close the cropped and padded image.

- Close the registered image (Registar will ask if you want to save - just click no)

- Close the image you just registered to the 'main one'. (Just to tidy the windows up and get rid of those you already did)

- Pick the next image and start over again - registering to the 'main'.

Once in Photoshop or similar open the 'main' one - and open the ones you saved, the ones ending with 'cp'. Then one by one 'select all' on an image, 'copy' - make main active and paste into the 'main'. It will be a new layer with stars etc perfectly matched. Then finally chose blend mode to bring them all together. 

Registar has many variants to offer on the same theme here, the above is just a routine that I find simple to follow and understand. Once you've done it once, you will not need to read this again.

/Jesper

[Nathan_Pembs]

Thanks Jessun, I've just gone through your guide and it seems simple enough I don't think I had the best subs to try out Registar with, so fingers crossed for some clear nights soon.