I have recently started to use ASTAP image inspection to help making judgments about collimation.
I look at the eccentricity or to be precise the ASTAP unroundness values of stars. However the image inspection only gives one digit numbers, which I found to be of limited value due to the lack of precision.
Would it be possible to get the numbers with a higher precision ? Two digits would make a big difference.
Thanks
CS
Gernot
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The measurement works better for larger "stars". So for any testing it is best to set binning at 1x1 for best accuracy unless you have a OSC sensor. For OSC it is better to bin 2x2 the raw..
I will release a new Linux and Windows version next hours.
Han
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Just released. It was a coincidence. I was just making some other minor changes.
Measuring roundness/aspect of a star is pretty difficult. The problem is that most flux is located in the center. The star tail doesn't contain much flux so there is a lot of noise in the signal. Maybe measuring the tail only is a better option. Or just count all pixel values above noise level equal. Something for the future.
Han
Last edit: han.k 2022-09-27
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
I have recently started to use ASTAP image inspection to help making judgments about collimation.
I look at the eccentricity or to be precise the ASTAP unroundness values of stars. However the image inspection only gives one digit numbers, which I found to be of limited value due to the lack of precision.
Would it be possible to get the numbers with a higher precision ? Two digits would make a big difference.
Thanks
CS
Gernot
I have changed it now to 3 digits.
The measurement works better for larger "stars". So for any testing it is best to set binning at 1x1 for best accuracy unless you have a OSC sensor. For OSC it is better to bin 2x2 the raw..
I will release a new Linux and Windows version next hours.
Han
wow, that was quick !
Thanks a ton.
Also thanks for the recommendation. I am using OSC, so I know now how to get the best out of the data
CS
Gernot
Just released. It was a coincidence. I was just making some other minor changes.
Measuring roundness/aspect of a star is pretty difficult. The problem is that most flux is located in the center. The star tail doesn't contain much flux so there is a lot of noise in the signal. Maybe measuring the tail only is a better option. Or just count all pixel values above noise level equal. Something for the future.
Han
Last edit: han.k 2022-09-27