|NGC 4567 and NGC 4568
Interacting Galaxies in Virgo
Colloquially known as "The Twins" or "The Butterfly Galaxies", this pair of spiral galaxies is
approximately 116 million light years from Earth in the Virgo cluster of galaxies. The large elliptical
galaxy NGC 4564, the small spiral galaxy PGC 42079 and the faint dwarf galaxy PGC 42075 are visible,
along with numerous smaller galaxies.
Date: April 19-May 20, 2007
Camera: SBIG STL6303E
Filters: AstroDon LRGB
Camera control software: CCDSoft
Guiding/adaptive optics: AO-L with Astrodon MOAG-A off axis guider/SBIG remote guide head
Camera temperature: -20C
Image Acquisition Software: CCDAP3
Telescope: RCOS 16 Carbon Tube, Aries optics, F9 with Field Flattener
Telescope control software: RCOS TCC, TheSky6
Mount: Paramount ME (MKS 4000)
Total exposure time: 1,090 minutes
Luminance: 49 x 10 minute, binned 1x1 (best 49 of 67 total Luminance exposures selected)
RGB: 21 x10 minute Red, 20 x 10 minute Green, 19 x 10 minute Blue, binned 2x2
Conditions: Seeing conditions over 4 nights averaged 2-2.5 arc sec; target elevation from 46 degrees to
65 degrees. Altitude of observing site: 720 feet.
FWHM of combined Luminance data: 2.2 arc sec raw, 1.65 arc sec deconvolved.
Processing: CCDSoft, Sigma, CCDInspector, MaximDL, MiraAP, CCDSharp, Photoshop CS3.