Rob,
You have some choices.
1) Use eyepieces that require less back focus.
2) If you're close (doesn't sound like it, but if so) you can sometimes create a little back focus by moving the mirror cell forward on its collimation bolts (put them all as far forward as they can go and then back off a little for adjustment purposes).
3) If it's a tube scope, you should be able to mount the mirror cell a little closer to the secondary by drilling new holes and moving the cell. If it's a truss scope, you might be able to shorten the truss poles. (I haven't seen how they attach, so seek advice on this.)
4) A different focuser might provide more back focus (as you mention).
5) If a tube scope, the focuser and secondary may be moved closer to the primary (but you almost surely won't want to mess with all that--it's more a theoretical possibility than anything).
Maybe there are other options, but that's all I can think of that seems reasonable at the moment.
--
Mike
You have some choices.
1) Use eyepieces that require less back focus.
2) If you're close (doesn't sound like it, but if so) you can sometimes create a little back focus by moving the mirror cell forward on its collimation bolts (put them all as far forward as they can go and then back off a little for adjustment purposes).
3) If it's a tube scope, you should be able to mount the mirror cell a little closer to the secondary by drilling new holes and moving the cell. If it's a truss scope, you might be able to shorten the truss poles. (I haven't seen how they attach, so seek advice on this.)
4) A different focuser might provide more back focus (as you mention).
5) If a tube scope, the focuser and secondary may be moved closer to the primary (but you almost surely won't want to mess with all that--it's more a theoretical possibility than anything).
Maybe there are other options, but that's all I can think of that seems reasonable at the moment.
--
Mike
