Enchanted Skies

Solar System

A Ring around the Moon (imaged from Las Cruces, NM)

Lunar Halo Map showing size and location of Halo

 

Object Information                                            Imaging Details

We don't get many halos here in the desert southwest, so when a bright halo occured on 11Dec, I decided to capture it using an ultra wide angle lens.

Halos, like rainbows are produced by light reflecting on water drops, dust and ice crystals in the atmosphere. Lunar halos show only very faint colors visually since the illumination is much lower. However, the color is there - it just needs to be enhanced a bit.

The challenge for a shot like this is to create a high dynamic range image that gives good colors, but doesn't blow out the Moon's shape (9-day old waxing gibbous phase in this case). So, several different exposures were taken.

The map on the right is to scale. The radius is 22°.

Clicking the above image will bring up a higher resolution image with a slightly larger field of view.

Telescope:

Canon EF 15mm fisheye lens

Camera:
Canon T2i (type 1 modified)
Filter(s):
 
Misc. Optics:
 
Exposures:
Several different exposures from 1/10" to 2" and various ISOs and f-stops.
Guiding:
Unguided (tripod mounted)
Processing:
Images converted to tifs using Photoshop CS5. Nebulosity used to stack the images. Additional processing (curves, sharpening) with PS CS5.

Home           Galleries          Solar System

Enchanted Skies - Astrophotography by Rich Richins (all images copyright, Rich Richins)