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lukebl

Deep Sky Stacker - manual alignment?

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lukebl    2,100

Is it possible to manually align the frames in DSS? I have an image that has insufficent stars for it to align on, so it just won't do it.

Selecting an object in 'Comet mode' doesn't help, as I still get the message: 'Only one frame (out of 15) will be stacked .... Do you want to continue'. How can I get it to stack all frames whether or not it can find any stars?

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lukebl    2,100
Isn't there a method of manually picking the stars? I'm sure there is?

You would have thought so. But I can't find it.

Basically I have a set of DSLR lights, flats and darks of Uranus & its moons, and there are only about 9 stars in the frames (including the Uranus system). The upshot is that I can't stack it in DSS as it tells me there aren't sufficient stars. I can stack it in Registax, but that only seems to accept one dark frame, and the final result is very noisy and with loads of bad pixels.

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Bizibilder    4,279

I seem to remember that one reference that I have (the one I can't find at the moment!) says that DSS won't stack less than 10 stars. If I find it I will confirm for you.

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martin_h    1,588

DSS needs 8 stars minimum....after looking at a few threads on the Yahoo groups there is no manual option....I've had the same problem, but I use Nebulosity2 for capture so can align manualy there.

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davew    264

This may be a long shot but can you use comet stack ? Select a star and see what happens ?

Maybe not.

Dave.

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martin_h    1,588
This may be a long shot but can you use comet stack ? Select a star and see what happens ?

Maybe not.

Dave.

Well I'm blowed it worked...I've just done a Ha stack that DSS wouldn't do before (not enough stars) so I've just done a comet stack on the bright star (Gamma Cass)..It was a pin ***** on the original subs.

post-16950-133877505006_thumb.jpg

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davew    264

Chalk up another one to a wild guess :)

Now we know.

Dave.

Also try the other stacking method in comet. See if the stars improve.

Edited by davew

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martin_h    1,588

I had to do it with "No Alignment" selected in the alignment settings because it kept on trying to count stars...I expect this will only work if there is no rotation between frames.

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Shibby    402

There is an "Edit Stars" mode (the big red star icon). This lets you sometimes add a few more that it "thinks" might be stars, by clicking on them. You have to do this after registering the frames.

Usually if there are enough obvious stars (which there easily are in your image, martin) then setting the detection threshold low enough and/or turning off the median filter will get DSS to detect enough of them. Don't turn off the median filter if there are too many hot pixels, though.

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