# 7 Sisters in LRGB



## griz (Jan 9, 2006)

LRGB is a processing technique that is used a lot in Astrophotography. Basically you split off a lum image from your stack and do the sharping and deconvolution on that image. Then recombine. It brings up the color and gives you some star color. Also decimated some of the small stars to make it less busy. Still amazed at how much data the 7D2 gets in 90 sec. Way more nebulosity than the 7D and the noise level is practically zero at ISO1600. Thinking about having the 7D modified for strictly astro use but the 7D2 is so good I've been holding off. Seems to me the red is so much more pronounced on the 7D2 the removal of the IR filter isn't necessary. And the noise level on the 7D is so much more that I'm not sure it would be of any benefit.










This shot is 20 images of 90 sec ISO 1600 7D2 and EF400

Pirelli Challenge next weekend at COTA. I'll be able to put the 7D2 to the test then. Hope the weather gets better.

Griz


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## MichaelW (Jun 16, 2010)

Your procedure for photos loses me, but love the shots. Nice work.


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## griz (Jan 9, 2006)

You can extract a luminescence frame from your color image. You sharpen and work on that image to get the detail then merge it back with the color. You can do more radical stretches etc with just the lum. Doesn't introduce artifacts or noise in your color channels this way.

The mount is now fully robotic. 7 hours of cable making and configuration and it came right up. Mistake on the wiring diagram I had so I had to trace that down. But that was the only glitch. Now if the weather would just clear up for a week I'd be able to get it fully tuned up. No more searching for targets now or running back and forth to the yard my legs will appreciate it 

Griz


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