Instrument

12.5" RCOS @ ~ f/9 (2880 mm fl) at 0.64 arcsec/pixel. Shown at  0.91 and 2.11 arcsec/pixel.

Mount

Paramount ME

Camera

SBIG STL-11000 w/ FW8 filter wheel & AstroDon Gen-2 LRGB filters.

Acquisition Data

 4/1/2016 to 4/22/2017 Chino Valley, AZ.  with CCD Commander & CCDSoft.  AOL guided

Exposure

eXcalibrator RGB ratios are 1.00, 1.07 & 1.00

Software & Processing Notes

• CCDSoft, CCDStack, PixInsight, Photoshop CS6.

• eXcalibrator v5.1 for (g:r) color balancing, using 30 stars from the SDSS-DR9 database.

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

• CCDStack to calibrate all sub exposures.

• PixInsight to register, normalize, data reject, combine the sub exposures, gradient removal, non-linear stretching with HistogramTransformation and to create the LRGB image.

• Noiseware 5, a PhotoShop plug-in.

• PhotoShop final touch-up includes background noise reduction and selective sharpening.

Comment

North is to the top.

Spiral galaxy NGC 2903 is only about 20 million light-years distant in the constellation Leo. One of the brighter galaxies visible from the northern hemisphere, it is surprisingly missing from Charles Messier's famous catalog of celestial sights. NGC 2903 exhibits an exceptional rate of star formation activity near its center, also bright in radio, infrared, ultraviolet, and x-ray bands. Just a little smaller than our own Milky Way, NGC 2903 is about 80,000 light-years across. 

Source: NASA APOD