Hi, Im new to this & have a Skywatcher 150P on a EQ3-2 motor mount, Im using it with my Sony a200 DSLR camera for astrophotography attached directly, The trouble im having is when the camera is attached using my T-mount adapter the object im viewing is very small in the camera viewfinder, even using my 2x barlow its still very small, I can get quite good focus, do I need a bigger barlow or am I missing some type of other adapter or lens?