optics-sept-7

A montage of a full range (10mm) focus sweep- focus 0 is at bottom left, focus 9500 is at top right.

Each image along a row has a focus +500 from the one before it.

To be concrete, the images in the left most column have, starting from the bottom, foci of 0, 2000, 4000, 6000, 8000 microns.

DES r-band 1576-1596, Object at CCD1 (same as last night, we just swapped the numbers in the fits file) row,col=2470,465.

The donuts are cleaner, more symmetrical, but the still distorted (at high focus) at lower right, huge astigmatism remains, and

of course, the central donuts. It is improved, but by a matter of degree.

A comparison with last nights DES r-band data, the new data on the right (the one with the cosmic ray).

The donut is, in fact, improved markedly. We aim at a circular, smooth in outline donut, and the

new one is better.

Hartmann trajectory, in frames 1604-1624 CCD1 (same as last night as number switched in fits file), row,col = 1615, 1755.

Following the idea that the points on the top plot that don't follow trajectories that cross a single point in the lower plot,

the first five bright spots starting from right to left are problematic; the bottom of the mirror.

Hartmann mask focus sweep, in frames 1604-1624 CCD1 (same as last night as number switched in fits file), row,col = 1615, 1755