It’s still not great imaging during August due to the continuing light evenings and early mornings, and I see from my notes that it is still getting on for 11.00 p.m. before it is worth setting up for an imaging session 
However, needs must, and we do our best given the circumstances, so what object do I choose for the Imaging Object of the Month for August? As I said last Month, we could still choose an object in Cygnus, and we could in fact keep going with our “mega-imaging” project if we started one last Month. But I fancy choosing something a bit different, and in a part of the sky I don’t spend a lot of time imaging in. For August 2008 I’ll pick the Cave nebula in Cepheus.
The Cave nebula [Sharpless 2-155, Caldwell 9] is a fascinating region of space in Cepheus containing dark nebulosity, emission nebulosity and reflection nebulosity - it is very busy - and a very rewarding imaging target. It is also rather faint and once again requires reasonably long sub-exposures of around 10-minutes for RGB with my system. You will also want to take some narrowband H-alpha to bring out all the faint emission nebulosity in the area.
You don’t need a wide field imager for this object, and if you’re specifically interested in the Cave nebula itself you’re better off with a narrower field of view than I get from the Sky 90/M25C combination. In fact the old Hyperstar setup had an almost ideal field of view for the Cave coming in at around 1.0 x 0.75 degrees.
Don’t worry - we’re about to leave our most difficult imaging months and September will once again bring dark nights to us at a more reasonable hour. All we then need is for the cloud (and Moon) to keep clear.
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