What is the maximum rotation SC can align?

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MikeHuerto
Posts: 15
Joined: Thu Jan 21, 2021 12:05 pm
Location: Spain

What is the maximum rotation SC can align?

Post by MikeHuerto »

Hi

I'm fairly new to SC, but its been working remarkably well for me in the past few months. I have been using my 14" GOTO Dobson with an ASI224MC to image M82 using various filters.

Last night, the the maximum rotation I was able to get alignment for was about 30 degrees - see attached JPEGS of first and last aligned image (originals were 1.3MB TIFFS).

The aligning stars were still clearly visible, so just wondering if SC reached its max for rotation alignment at 30 degrees, or were there perhaps other image quality issues at play?

FYI These M82 images were taken with a ZWO IR pass850 nm. For the final image go to: https://astrob.in/g4eb2q/0/

For M82 images taken with IR cut:https://astrob.in/db2trc/0/ and no filter https://astrob.in/knxypc/0/

Thanks for your help!

Mike
Attachments
last image stacked
last image stacked
frame_04106.jpg (499.71 KiB) Viewed 225 times
first image - aligned to
first image - aligned to
frame_00001.jpg (538.9 KiB) Viewed 225 times
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Re: What is the maximum rotation SC can align?

Post by admin »

Hi,

there should be no real limit to the rotation provided enough stars are found to guide the algorithm. I think a lack of stars might be the cause of your problem - I can see about 3 with the naked eye on those images - maybe SharpCap picked up some more faint ones. If one or more of the fainter stars that SharpCap was using have moved out of view you could find a situation where there are not enough left to make the alignment work. Overall, the best thing to do is keep an eye on the contents of the 'Alignment' tab in the live stacking area to see if that is the problem..

thanks,

Robin
MikeHuerto
Posts: 15
Joined: Thu Jan 21, 2021 12:05 pm
Location: Spain

Re: What is the maximum rotation SC can align?

Post by MikeHuerto »

Hi Robin
Thanks - yes last night I used the highlight alignment stars feature to keep track of stars being used. That helped a lot, and basically kept going until I was bored and cold! 3000 x 2 sec stacked and a few hundred dropped so something close to 2 hrs! Whilst tapping away with right index finger to keep the tracking stars in FOV.

Thanks again for a great program!
Mike
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Stack_3004frames_6008s_WithDisplayStretch copy.png
Stack_3004frames_6008s_WithDisplayStretch copy.png (102.09 KiB) Viewed 195 times
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