Luckily most of the performances measures so far show pretty good correlation to the norm of the WF error. Here's an example of the norm of the recon phase compared to the negative log of "sr2," which is the sharpness measure equal to the max intensity divided by the total image sum. Input was a spatially uniform sinusoidal disturbance command around the bias with an amplitude of 20V.
[Chr06a] suggests that the image sharpness is proportional to the Strehl, so its natural log should be approx. inversely proportional to the spatial RMS of the wavefront error (by the Marechall approximation). Seems to be about right if you squint.
The imaging sensor of the target camera isn't placed with the same accuracy as the other components, so its possible that minimized wavefront doesn't minimize the measured Strehl. I don't expect this to be a problem though since ultimately I'm going to be looking at the noise power, and I think unless the placement is way off with LTI controller should show an obvious improvement.
Here's a video of a random disturbance with the corresponding target image and reconstructed WF.
Well, obviously, we have a spot which isn't stationary, making power in the bucket measures somewhat useless. My advisor seems to favor these since they're nice to use in simulation when everything is perfectly on axis, so there's going to have to be some convincing before I can really use a different method.
Tomorrow I'd like to get the some sharpness measurements going w/ and w/o the LTI controller, assuming I can ever get it working without it shitting the bed.
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