Instrument

12.5" RCOS @  ~f/9 (2880 mm fl) 0.64 arcsec / pixel.  Shown at 1.00 and 1.54 arcsec / pixel.

Mount

Paramount ME

Camera

SBIG STL-11000 w/ FW8-STL filter wheel, AstroDon Gen II Filters.

Acquisition Data

6/6/2015 to 6/16/2015 Chino Valley, AZ... with CCD Commander & CCDSoft.  AOL guided.

Exposure

eXcalibrator RGB ratios are 1.00, 1.01 & 1.15

Software

• CCDSoft, CCDStack, PixInsight & Photoshop CS6. 

• eXcalibrator v4.30 for (g:r) color balancing, using 42 stars from the SDSS-DR9 database.

• CCDBand-Aid to repair KAI-11000M vertical bars.

• CCDStack to calibrate all sub exposures and creating the RGB image. Positive Constraint deconvolution, with 15 iterations, to tighten the stars and background galaxies.

• PixInsight processing includes registration, stacking and data rejection for the luminance, gradient repair and non-linear stretching, with HistogramTransformation, for both the Lum and RGB images. Finally, selective use of HDRMultiscaleTransform, with various layer counts, was used to enhance the detail of the galaxies.

• PhotoShop for the LRGB combine & final touch-up. 

• Noiseware 5, a PhotoShop plug-in.

North is to the top.

This beautiful group of galaxies is located in the constellation Virgo. The largest galaxy is NGC 5566 and is about 78 million light years distant. To the left is NGC 5569 at a distance of 92 million light-years. This galaxy shows no interaction with the other two. To the right, and 90 million light-years away, is NGC 5560. NGC 5566 and 5560 are an interacting pair.

On the right end of NGC 5566, we can see a faint plume extending towards NGC 5560. The nearly edge on view of NGC 5560 shows distortion and a faint tidal extension toward the center of NGC 5566.

The full-frame image contains five distinctly blue quasars with redshifts from 1.07 to 3.60 and magnitudes of 19.3 to 21.0.