Got the 5700 yesterday, haven't had much of a chance to play around with it yet, still reading through the manual.
Looks like it should be pretty good though, but the shutter lag is a little too long for my liking -the Sony was really fast.
You wouldn't believe it either - the police rang this morning and someone handed in my Sony yesterday! 2 days after I bought a new camera! aarrgh! Now I have to decide which to keep and which to sell.. i know my wife will want to keep the sony for it's speed and simplicity.
But the nikon is good for 8x optical zoom and 5 minute bulb mode!
Starkler to answer your question, *I* don't use any adapters, though I wish I was using one.
I've been using a fixed tripod with the camera on top, and pointing the camera into the eyepiece. However it's a pain in the neck with the dob because you have to continually move it.
I'm going to get (or make) a steadypix adapter:
https://www.bintelshop.com.au/Product.aspx?ID=6705
There's also some adapters at
www.scopetronix.com - quite pricey though, around AU$300 with includes an eyepiece and the adapters required.
Good luck, and post your results!