PUEO's second engineering run images
This is an image of the center of the globular cluster M71 at I band (830
nm). FWHM is 0.10 arcsec (center) to 0.18 arcsec (edges). The natural
seeing was 0.30 arcsec (excluding tracking errors and telescope fixed
aberrations). This is a 1200 seconds exposure.
Same field in the V band (545 nm). FWHM is 0.12 arcsec (center) to 0.21
arcsec (edges). The natural seeing was 0.28 arcsec (excluding tracking
errors and telescope fixed aberrations). This is also a 1200 seconds
Image of a 8.6 R magnitude star in the I band. The FWHM is 0.068 arcsec.
To our knowledge, this is the crispiest long exposure image ever from
ground based observations. The Strehl ratio is 13\%. Integration time is 2
seconds, which is kinda short but is sufficient to get a meaninful average
in close-loop. D/r0 is 9.4 at 0.5 microns.