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graham.hobart
30-06-2014, 09:49 AM
I have a canon 5d mark II on a WO GT81 which at 535mm fl gives a pixel resolution of 2.46" per pixel.
I have an Orion Eon 110mm which f6 at 110mm =660mm xo.8 Williams optics reducer flattener which gives 528mm fl which is 2.36' per pixel with my QHY 10.
IS there a way I can combine lights from both cameras ? Seeing as the pixel resolution is so close?

I haven't tried anything yet but would love advice on how to go about as have multiple subs from both on the same subject.
Any help greatly appreciated:thumbsup:
Graz

RickS
30-06-2014, 10:18 AM
Yes, you can combine the data from multiple cameras. You just need to use image registration software that's capable of scaling the subs to match exactly. I think most processing packages are capable of this. PixInsight certainly can do it.

Cheers,
Rick.

graham.hobart
30-06-2014, 10:47 AM
Cheers Rick, any alternates apart from PI? Can DSS re scale?

graham.hobart
30-06-2014, 11:33 AM
in pixinsight is it automatic or do you have to tell it what to do?
What happens if you are combining two sets of subs with different bayer settings? is it - debayer first, calibrate each lot separately then combine?

RickS
30-06-2014, 11:57 AM
Sorry Graham, not sure about DSS.



It will scale by default.



You have to debayer and calibrate before you do image registration. That's the case whether you're using two cameras or just one. Debayering and calibration both rely on pixel position and registration will move things around.

Cheers,
Rick.

graham.hobart
30-06-2014, 12:01 PM
Thanks Rick for prompt replies- will have a go this week

PRejto
01-07-2014, 01:02 PM
I'm doing this currently with my KAF8300 chip on my TEC180 and H694 chip on my TEC140. This gives similar (but not as close as your situation) resolutions and FOV. CCDStack does this automatically when I tell it to register the images.

Here is an image that I did where I collected lum with the TEC180 and colour with the TEC140:

http://www.pbase.com/prejto/image/155539657

Peter

graham.hobart
01-07-2014, 01:34 PM
Hi Peter, thanks. Many times I have now encountered CCD stack so it seems motivation is amassing to buy it!
:thumbsup:

MrB
01-07-2014, 05:03 PM
I just yesterday trialed the demo version of Nebulosity and noticed it can scale while registering images too. Worth trying, only a 16MB download and fully functional, tho the demo leaves lines on the finished image.

LewisM
02-07-2014, 02:24 PM
CCDStack definitely does it, and thoroughly recommended. It works FAR better than DSS and is simpler than PI.

gregbradley
03-07-2014, 11:55 AM
Registar is one of the best for this type of work. CCDstack should be fine as well although occassionally it is trouble.

Greg.

graham.hobart
03-07-2014, 01:30 PM
Thanks guys.
I am pondering how to go about it now. I have downloaded the trial version of CCDstack.
Is the principle - A/ debayer and calibrate frames from each camera then produce a master light from each then combine Master light 1 and 2 ?
Or debayer and calibrate each then stack them all together?

marc4darkskies
04-07-2014, 12:38 PM
Not sure what PI does but RegiStar shifts, scales, rotates, and deforms images to register precisely. The ability to deform is important when stacking images taken through different optical systems, esp at small image scales. CCDStack does not deform images.

RickS
04-07-2014, 03:43 PM
Both options would work but I'd expect that combining all the frames in one integration would produce the best results (gives the rejection algorithm more data to work with.) Try both and compare the results...



PI is able to deal with distortion as well as simple translation, rotation and scaling.

Cheers,
Rick.

Octane
04-07-2014, 03:46 PM
I was impressed by IRIS's ability to transform images from different systems, but, PI takes it even further.

H

graham.hobart
04-07-2014, 04:09 PM
The question (regarding CCD stack) is then-
Seeing at is produces a master flat master dark and master bias, is there some way of telling it to take two sets of calibration masters and apply to each light frame then stack together- as I believe it would just stack my lights into a master calibrated stack before I was able to combine- can I calibrate register and then save the calibrated files before I stack them? I can see the registration option and then star snap - apply etc
I take it I can just calibrate then save all the files into one mega file then add them later ? Does it debayer automatically when calibrating ? (else would it get confused with two different debayer algorithms?