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VPhot Issue with black image

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VAastro
VPhot Issue with black image

I tried downloading 3 images this morning into VPhot.

The "Available Images" page shows that the images are okay.

When I click on an image I get a black image.

I am attaching the 3 screen shots.

The last image is one of the .fit images I submitted to VPhot.

I tried loading the 3 .fit files and the 3 zipped .fit files and I get the same black image.

 

MZK
MZK's picture
Astroart

Erik:

Is this the first time you have used astroart for imaging and uploading to VPhot? Sometimes the stretch is done unusually and the black/white levels are not as expected by VPhot and you get a black image.

BTW, the last attachment is a gif file not fit file.

Ken

VAastro
Astroart

Ken,

Thanks for input.

I always use Astroart for imaging and uploading to VPhot.

This is the first time this has happened, The last attachment is indeed a snapshot of the .fit file.

MZK
MZK's picture
Astroart Images

Hi Erik:

Certainly will be interesting to see what happens to your next group of images. I can see images currently in my image list today with no issues. I have seen this happen on a few rare occasions but never came to a final conclusion of the cause.

Any small changes to your procedure that might be a clue? I suspect not?

Can you share the images to me at MZK?

Ken

VAastro
Astroart Images

Ken,

I have shared the three images with you.

Thank you

Erik

MZK
MZK's picture
AstroArt Images

Erik:

As I suspected it appears to be the avisumin and avisumax headers that astroart puts into the image. It has to do with "visualization" / white/black levels?? Do a google search. Look in the headers for the three images you shared. One of them is different and I can see the stars for it. Not sure the headers can be changed without a fits header changer program?

Ken

VAastro
AstroArt Images

Thanks Ken

Will check this out

Erik

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