Affiliation
American Association of Variable Star Observers (AAVSO)
Mon, 05/01/2023 - 13:59

Dear observers, would you please explain, why my uploaded FITS file turned in absolutely blank VPhot image?

FITS & JPG are here.

Affiliation
American Association of Variable Star Observers (AAVSO)
Screen Stretch

Mikhail:

White because the screen stretch your processing software used is not within the normal range that VPhot expects. I tried to fix it under tools>display without success.

You might try saving it as a 16 bit, not 32 bit, image in AIJ and upload again?

Ken

Affiliation
American Association of Variable Star Observers (AAVSO)
32 ->16

Yes, yes, thank you! Indeed after saving in 16 bit all stars disappeared.

But camera gives 16 bit gray image, and 32 I got after stacking. Well, I'll try to correct my clumsy processing, now the reason is known.  

Affiliation
American Association of Variable Star Observers (AAVSO)
Blank fits image

Is this a image that you processed.  I have seen this if I save a image as a 32 bit fits. It should be saved as a 16 bit fits filts.

 

Mike

Affiliation
American Association of Variable Star Observers (AAVSO)
16 bit helped, but all…

16 bit helped, but all bright stars have white circle in the center - I think, it shows on oversaturation?

Probably, better to try single shot or other type of stacking. Maybe better to stack 30 10-sec frames in VPhot, but what to do with flats and darks?