Hi John,
Thanks for your hard work, and very useable script!
This post is a continuation of the work started in my Post #31 on P2 of this thread.
I did a little study by comparing Image Integration via NSG script, vs the standard way of Image Integration with Noise Evaluation for weighting.
Attached is a file with several charts.
This data is based on high and varying background level data (659mm focal length) of M101. This where the NSG script should shine.
I wanted to see the correlation between the NWEIGHT and other factors when integrating without using NSG script.
Weight in normal integration (no NSG) was from the process console. At this time I have extracted only 40 frames of data from the process console.
I used Subframe Selector to get MAD, stars detected, and median from the frames used in normal integration.
I used same reference image for NSG script, integration after NSG script, and for normal integration.
In the end I asked myself:
1. Do registered individual images that look bad correlate better to NWEIGHT or to Weight from normal integration?
My answer; it varies:
-- All images that look bad have low NWEIGHT, but also some of these bad images also have low Weight from normal image integration.
-- No images with that look bad have high NWEIGHT. So NWEIGHT does not let me down.
2. Is the image after image integration looked better with NWEIGHT vs normal integration weights (no NSG)?
My answers:
-- The background gradient is better (simpler gradient to fix in DBE) using NSG script.
-- The normally integrated galaxy color is different (more blue after unlinked stretch). The NSG integrated galaxy looks brighter, but the readout data does not show any difference (out to 3 decimal places).
It is hard for me to say if the image quality is significantly different.
-- The edge goes to NWEIGHT integration.
-- Perhaps the final image quality is not significantly different if the weights are not exactly correct.
Any comments/questions/next steps I might do?
Thanks,
Roger