And with care, trusses work really well. With my 20" all the trusses are numbered so they are set up in the same order each time. I always set ip up in the vertcal position and tighten the knobs in the same order. Usually needs no more adjustment than my old solid tube 12" (and often less!)
My other scope is an 8" travel scope using just 2 square tubes instead of a truss and it also holds collimation very well, only needs a bit of tweaking.
I think it is more the quality of the cell, mirror supports, collimation mechanism and secondary mechanism that affects how well a scope holds collimation rather than the type of design.
Malcolm
Quote:
Originally Posted by raymo
Hi Suzy, I don't want to hijack the thread, but it is just not true that
solid tubes hold collimation better than collapsible ones; with truss
tubes it can apply, but definitely not with the SW Flex Dobs. They are
seriously rigid. In fact, my 10" Flex requires tweaking less often than my 8" solid Newt.
raymo
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