A more or less daily photoblog with favorites of my photographs. Subjects are typically nature, landscape, astrophotos, existing light.
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Tuesday, December 10, 2013
Lunar Halos on Kitt Peak
In case anyone is wondering why I'm not doing any observing early this evening, the sky over Kitt Peak is covered by a thin haze and the first quarter moon is producing a very bright halo in the sky. This image includes the Spacewatch 36 inch telescope dome in an image with my 10mm fisheye lens on my 70D with an exposure of 8 seconds at f/2.8, ISO 400. The 22 degree halo is quite prominent in this image.
I took a little hike over past the Steward Observatory 90 inch Bok Telescope and got this heavenly picture of the lunar halo around the dome. You can see that they were open, though I can't imagine they are getting any useful data.... The exposure was 20 seconds at f/5.6, ISO 1600 with my 10mm fisheye lens on my 70D. Not only is the 22 degree halo prominent, but I think you can also make out the 46 degree halo faintly, especially in the preview image.
And finally at the top of Kitt Peak, here is the 4-meter Mayall telescope under the moonlit sky. This exposure with my 10mm lens on my 70D was 20 seconds at f/5.6, ISO 1600. It almost looks like daylight in this image, but I can assure you, it was just a long exposure in the moonlight. The 4-meter was also open despite the cirrus all over the sky. The faint 46 degree halo appears to visible in this image as well which convinces me that it really was visible.