M65/M66 Enhanced Hydrogen Comparison

Galaxy Pair in Leo

Uploaded 4/21/08

North up in these images
Select an image size for a larger view: 1024 x 768 1600 x 1200
Select an image size for a larger view: 1024 x 768 1600 x 1200

This 12 hour - or Half a Day total exposure of this stunning pair of very different galaxies in Leo invites comparison down to the smallest hydrogen details. The image on the left is a standard 8 hour LRGB image using standard processing methods. On the right, an additional 4h of hydrogen data was added to each color channel in the correct proportions to yield a true color hydrogen enhanced image.

Certainly the largest difference is in the very active star forming galaxy M66 on the left. This 9.7th magnitude SAB spiral spans 9 arc minutes in length. So rich are the arms with hydrogen in red light that the nebulosity obscures much of the blue arms in the second image. On the right, the nearly edge on M65 is far more yellow in color and has much smaller less active star forming regions. The additional hydrogen appears as small patches and tiny spots in its dusty arms. M65 is fainter at 10.3rd magnitude.

Instrument: 12.5" f/5 Home made Newtonian Mount: Astrophysics 1200 QMD CCD Camera: SBIG 10XME NABG with Enhanced Water Cooling Guider: Meade DSI Pro w/Lumicon Newt Easy Guider Exposure: LRGB = 480:40:40:40 Exposure: Ha+LRGB = 240:480:40:40:40 AstroDon RGB Combine Ratio: 1: 1.05: 1.6 Location: Payson, Arizona, Elevation: 5150 ft. Sky: Seeing FWHM = 4.5 arcsec (Maxim DL - 10min subframe), Transparency 6/10 Outside Temperature: 45 F CCD Temperature: -30 C Image Processing Tools: Maxim DL: Calibration, deblooming (Starizona Debloomer), aligning, stacking PixInsight: Curves, Deconvolution Photoshop CS2: Curves, Color Correction, Gradient removal (Grad Xterminator), Cleanup HOME GALAXIES EMISSION NEBS REFLECTION NEBS COMETS GLOBULARS OPEN CLUST PLANETARIES LINKS