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DSLR Lens - funky blue stars
Been playing around with my polarie and i believe i have it all down pat.
My only problem though is that i am getting some weird stars in my shots.
Attached is a backyard test shot in the m8 area. 30sec at ~9mm (APS-C sensor) using a Sigma 8-16mm wide zoom lens @ f4.5, 1600 ISO.
The bright stars on the left hand side (blue) looks rather terrible.
Is this simply a lens design constraint that it has issues with blue light?
Possibly bad chromatic abberations?
It is less of an issue with less exposure, say 15sec the stars don't distort too badly.
I tried another lens - this time a Sigma 18-200mm zoom. Ran it at 180mm and the issue is still there with blue stars. It also has the joy of reflections on bright objects, but i'm not too fussed with that lens as it was only $250~ and i don't plan on using it. I uploaded a copy of it as well.
Will be heading out west next week to some dark sites so would like to put the DSLR and polarie to full use.
If i can figure out why my stars look so terrible.
Cheers.
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