Note fingerprint on grating surface. This is the original grating. I replaced it after construction, but before the Test Set 1 spectrums. The focus was then corrected shortly after - after focus spectrums.
20210117_190645
20210123_121724
Note fingerprint on grating surface. This is the original grating. I replaced it after construction, but before the Test Set 1 spectrums. The focus was then corrected shortly after - after focus spectrums.
