Vendor - Optical Supports
Last week I connected my Rebel XT to my telescope for the first time using a Zhumell 1.25" T-adapter and EOS T-ring. I quickly found that I couldn't rack the focuser in far enought to bring the camera into focus.
Would a tele-extender such as those linked below fix this problem?
Probably not. You have the short focal plane problem common to many reflector scopes designed for visual useage. The easy method would be to move the primary mirror up tube a couple of inches. A TC would help some but not enough to reach the DSLR focal plane. Point the scope at a bright image, then use white cardboad to determine the focus point distance from the side of the tube with no EP. Then mount the camera fully racked in to determine the distance to the camera CCD (marked on the top of the camera with a circle with a line through it). This will give an approximate distance that the primary mirror has to be moved forward.
Nikon D40/D50/D70 DSLR
WO 105mm Triplet APO
WO Zenithstar 66SD APO (Black 'n Blue)
WO 8 x 45mm APO Bino
UO 20 x 80mm Bino
Vixen 80SS Refractor
Orion 127mm Apex Maksutov
Vixen GP-DX with Skysensor 2000
SBIG STV and e-finder
Loc: Beaverton, OR, USA
probably not, as Barry says. (I actually posted something similar to Barry's explanation on your other thread before I read Barry's response here).
bear in mind that tele-extenders are designed to increase magnification for planetary photography. For deep sky photography, they're definitely not what you want. Additional magnification in that case is usually bad...
QSI 583wsg / StarShoot Autoguider
Celestron EdgeHD 11 / 0.7x reducer (new arrival)
150mm f/5 Newtonian, Baader MPCC