M51 Unfiltered Plus Halpha from Stinger 450 Classical Cassegrain and FLI IMG1024S Dream Machine

Unfiltered: ~2hours

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Taken on April 10, 2008 from my backyard in Castro Valley, Ca.

2 hours unfiltered + 3 hours Halpha

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Halpha data taken on April 11, 2008 from my backyard in Castro Valley, Ca.

Stinger 450 Classical Cassegrain (18" f/12.6)  

Lumicon Giant Easy Guider with Focal reducer for final: F= 3366mm, f/7.1

Finger Lakes IMG1024S "Dream Machine  imaging camera operated at -37C 

Robofocus

Finger Lakes CFW1 Filter wheel

Custom Scientific 4.5 nm AR coated Halpha filter (50mm unmounted)

SBIG ST7E guide camera

39 exposures of 3 minutes with no filter

18 exposures of 10 minutes through Halpha filter

4 hours 57 minutes total exposure time