Sorry to resurrect an old thread, but I'm having the exact same problem and don't really undestand the solution, so can someone spell it out in "Numpty" language!?
Okay, so I've got a 400D and a Skywatcher Skyhawk 114M scope. The scope comes with 10mm, "Super 25" Wide angle and 2x Barlow Lenses. I purchased a Celestron T-Ring adapter for the camera, and received in the post today a Celestron T-Adapter. The T-ring and adapter screw together, and the camera fits nicely to the scope.
But the focus range in Prime mode is dire...perhaps 2 to 4 metres focal distance over the entire range of the eye-piece.
What was that about holding a piece of paper over the end of the scope, with no eye-pieces, to determine the focal distance? A piece of paper isn't in focus even when touching the end of my scope! I have to feed something right into the scope to get it in focus! (And even THEN it doesn't appear to focus sharply!)
I wonder if there's something wrong with my scope!? I've used it with the eyepieces for celestial viewing, and have been very happy with it so far, but I dearly want to be able to take astrophotos.
If I connect the 2x Barlow lens I think this is going to work. Earlier in the day, when testing my new adapter, I was trying to focus on the trees outside my window. Couldn't at all with no lens, (they're only a few metres away!), but with the Barlow I could focus on them, and past, so I'm hoping that's at least going to let me focus on the moon or something later, (if these clouds clear).
Any suggestions appreciated.