Using data from multiple runs

[DDolan1075]

I will start by pleading ignorance.  I have had a bad run on hardware and software use in astrophotography and basically have to start all over whenever I try to image.  But enough of that...

I have some data from last year that I shot of Orion that used the same telescope but a different camera a D800.  I also used a 90 degree diagonal to keep from having to lay on the ground to see the back of my camera (last year).
This year I am using a D810A and not using the diagonal.

Several issues that I would like to know about:
1) there is a rotation between shoots.  does that matter?
2)  The previous images are mirrored by the diagonal and so I was wondering how to combine data.  Do you process individually or flip before processing and combine them.  And if you flip them do you flip and save and then load into batch preprocessing ?
3)  Also does Pixinsight know which darks to use with which images when using different cameras if you are throwing everything together?

Thanks for your help,

Dave

[pfile]

1) no

2) interesting question - i don't think i've ever tried to register a mirrored image to a non-mirrored image. you might try it with a couple of frames and see if StarAlignment will do it. if SA can't handle it, look into ImageContainer as a method to batch-mirror all your calibrated subs.

3) you should separately calibrate the images from each camera - it's not a good idea to mix up even cameras with the same sensor type, and here it won't work because the two sensors have different geometries.

rob

[Alejandro Tombolini]

Hi, I think that StarAlignment can handle mirrored images when setting "Triangles" as Descriptor type in Star Matching section.
BBP script has Triangles similarity set by default, so it should work for the mirrored images.

Saludos,
Alejandro.

[DDolan1075]

So if I want to use data from two cameras, how do I combine? I have processed both runs, so I have run through the batch preprocessing script with them separately .  Is there a way to combine calibrated data? To tell you the truth, I am not sure what the output files of Pixinsight are used for, or even if I should be saving all of those files, but it seems to me that those images have been calibrated/registered using the darks already.  Is that a bad assumption?

[pfile]

your assumption is correct - the BPP script is going to leave you with master bias and dark frames, a master light frame (the integration) and a whole slew of subexposures: the calibrated subs, the calibrated & debayered subs, and the calibrated, debayered and registered subs.

if your 2nd BPP did not use the same registration reference image as you used in the first, your two master lights are not going to be registered to one another. if that's the case, you can either register one of the master lights to the other, or re-run the 2nd BPP using the same registration reference that you used in the 1st BPP. or you can use StarAlignment to manually do this by loading the reference frame from the first BPP run as the reference and adding all the debayered subs from the 2nd BPP run as the target images. then integrate the resultant registered frames using ImageIntegration.

then once you have the 2 registered master lights, load those two master light images twice into ImageIntegration (II should be reset first as the defaults are fine for integrating masters). you have to load them twice because II requires 3 or more images.

rob