Technical Data
|
Optics |
Sigma 20 mm
f/1.8
|
Focal Lenght |
20 mm
|
Focal Ratio |
f/4
|
Exposure Time |
1h10min
(single
exp of 10 min)
|
CCD |
Canon EOS 5D
with baader filter
|
Location |
Colle
dell'Agnello (CN,
Italian Alps) at 2700 m height
|
Date
|
9 Aug 2010
|
Mount |
Kenko NES
|
Tracking |
none, only AR
motor
|
Temperature
and humidity |
T=+6°C,
RH=50%
|
Sky brightness at zenith (with SQM-L) |
21.7 mag/arcsec^2 |
Notes |
Thanks to
Emmanuele Sordini for loaning me his Canon EOS 5D mod! The image was
heavily stretched, so the brightest parts of the Milky Way was burned
out.
Unfortunately
this objective is not fully corrected even at f/4 (full aperture
f/1.8), as the stars on the corners shows.
|