Different file size with a ASI2600MM

park123

Hello all
I have a very strange issue with my ASI2600MM.I have had it for some time now and have been using it on the REDcat wide-field imaging train.I took it off the other night and put it on my 16inch telescope.After a night of imaging, I took some calibration frames.All went ok I thought.I started to process the images and I was getting error messages that my flat frames were not the same size as my lights.Very strange.I looked into it and to my surprise, the file sizes were different my bias frames were 12720KB Darks 12720KB lights 12720KB but my flats were 12727kb.So I redid the images and got even stranger results at binning 1X1 light frames were 50971 but the calibration frames were 50966.All the settings etc were the same gain etc.So I looked back on unprocessed data and I can see the light frames were all over the place at bin 1x1 50069 to 50971.I tried NINA SGP and the ASIair all with widely different results.I also checked the power to make sure it was the same and it was.The temp was -20 for all the setups.I have multiple other ASI cameras with no problems with the file size???This is really mucking up my imaging as my calibration files are different so making my night's images wasted.Other than this the camera seem ok cooling well etc.But I have no idea what is happening and ideas???????

Many thanks
Stu

w7ay

park123 But I have no idea what is happening and ideas???????

If you are looking at the size of the FITS files, they could indeed be different, since the length of the FITS headers can vary (temperature changing from 0 to -20, for example, or exposure times that are different, or filter names with different string lengths, etc).

However, what is important is the image (sensor) size, not the file size. Use a FITS inspector to see if the image sizes are the same. The FITS inspector should also explain why the file sizes are different.

Chen

park123

Hi Chen thanks for the response.I will do as you say but something is up as the files will not calibrate I get an error message saying file size is different.Will let you know
Stu

jdiregolo

I have the same issue with my camera . ASI 2600MC Pro just wondering if my portable 1TB Sandisk drive is adding to the fits header?

Tech@ZWO

jdiregolo What software you use to take these fits files? usually, the storage position is not included in the fits header.

deans

I found that if I use SkyX for imaging then it also set different sizes than when using the ASIairPro. So I end all my folder names with either an X or Air to designate which I used.