I have two short telescopes. The tubes that the eyepieces fit in are different; one is short and one is long, such as the tubes on the Celestron first scope and the Jason Comet chaser. Why is this so and what is the advantages of one over the other? They both take 1.25 eyepieces.
The reason that some telescopes have long eye-piece tubes is that the focal plane of the objective has been placed far enough outside the main tube assembly to allow erecting prisms or binocular adapters to be fitted, if desired.