||Total 10 h 40 min, composed of L-RGB 380:70:70:120 min
(single exp of 10 min)
||SBIG STL-11000M @-25°C and @-40°C
||Saint Barthelemy, Passet (AO, Italian Alps) at 1900 m height
|24-25 February 2017 (2 nights)
on an 80mm f/5 refractor
||T= (-4 to -8) °C, RH=(50 to 70) %
|Sky brightness at
zenith (with SQM-L)
||(21.3 to 21.7) mag/arcsec^2
||Very bad seeing on the first night (10" FWHM !!!). A lot of frames has been discarded.
Problems with ice on the sensor in the first night, so I limited the
cooling to -25°C; then the desiccant was "cooked" in our caravan and
the problem disappeared even cooling at -40°C.