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Re: VENUS, MARS, MOON ... and upcoming Camera doubleLunars ?
From: Peter Monta
Date: 2015 Feb 22, 21:41 -0800
From: Peter Monta
Date: 2015 Feb 22, 21:41 -0800
Hi Kermit,
And, to you Peter, what were your observers elements : UT and Position ?
Position: N 37.3184 W 122.0306
Time, photo 1: 2015-02-21 02:29:36.2 UTC (2-second exposure)
Time, photo 2: 2015-02-21 02:56:11.2 UTC (4-second exposure)
The times are derived from timestamps saved by the camera, corrected by a bias that I keep track of by photographing my phone running an NTP app (Emerald Timestamp). Should be good to 0.2 second or so. Of course that is well below the accuracy required for this relatively slow event.
I can certainly send some original camera images if there's interest. I have a number of them with various exposure times, including some short enough so as not to saturate Venus and the bright lunar limb. The camera saves both JPEG and Canon's raw format, CR2. There are also FITS files, derived from the CR2, with some reasonably correct metadata included (such as distortion terms slightly modifying the nominal 6.97 arcsec/pixel scale). (The images I posted the other day are cropped and rescaled, but no other processing aside from that.)
Cheers,
Peter