Hi Brian, First point is that most dobs will not come to focus with a DSLR
attached, being made for visual use, not imaging. I don't know about the Lightbridges; no doubt someone here will tell you. Even if it will, it is almost useless for imaging. Because it can't track objects, your longest exposure will be less than a second before stars begin to elongate.
You can get quite good lunar or solar pics[ with a proper solar filter].
If the Lightbridges can be fitted with a "Go To" system, and you fit one, you will still be limited to short exposures [around 20-30 secs] because of
a thing called field rotation.
The kind of imaging you refer to can really only be done with a motorised equatorial mount.
raymo
With your camera you are better off buying a lens for it and doing some wide field astrophotography. With a decent lens you'll be able to take some breath taking photos