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First clear night in a while here so out came the scope to show a few objects (M27, M24, M8, M13, M16, M17, M20) to visitors around midnight. Once they'd got bored/tired an hour later I star-hopped from M9 down to Barnard 72, the Snake (dark nebula) which was 24 deg above the horizon at the time. This is the first time I've looked at a dark nebula but definitely won't be the last! 

This is a 60s exposure re-using a master dark from an earlier session (on the basis that visitors, midnight and waiting for darks don't mix  :smiley: ). I really had to home in on the histogram (i.e. use a very small range between white and black points) to get this. The good thing about dark nebulae are that they provide a good calibration point for the black level...

post-11492-0-62355700-1403856890_thumb.p

Cheers

Martin

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Thanks Knight of CS. I also took a look at the chain of Barnards just to the south but the clouds were coming in. Definitely an area to explore further. I think I was fortunate with the timing (1.30ish) to catch them at culmination. The image was taken under some LP too (a few streetlamps) and without filters. I'll try again from a darker site at some point.

Thanks Paul. Its the only one I have apart from the dob so I have no choice! I'd like to see what difference an APO of similar aperture makes -- quite a lot I imagine for a dense star-field like this one.

Martin

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Wow - that has come out really well!! I always thought these types of object would require really long exposures to get anything out of them! Great result!  :grin:

There is even hints of the brown dusty colour too!

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Wow - that has come out really well!! I always thought these types of object would require really long exposures to get anything out of them! Great result!  :grin:

There is even hints of the brown dusty colour too!

Thanks Paul. I was surprised too how well it came out in a brief exposure and also the colour being about right -- the latter more luck than judgement I think. 

The other surprise for me was capturing these under some light pollution without filters and with intermittent clouds. I was led to believe that a dark sky is required for dark nebulae (though I don't really see why since they're visible as by contrasting against a bright starfield). 

Martin

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I agree - I would have thought dark nebulae would be more visible - I must admit I have never tried to spot one visually - defiantly something to try at some point!

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