Last night I was enjoying some doubles with my 120mm F/8.3 achromat. About 10:30, I remembered this thread. Porrima was at about 40 degrees and clear of the trees so I gave her a try.
In the 120mm, it was a beautiful split but a low magnifications, under 80x, there was no way I was getting a clean split. The achro optics combined with the large exit pupil and my old eyes meant I needed some magnification. Next time I will try it with my 80mm apo and see what I can do.
While I was lined up with Porrima, I decided to give it a try in the finder. It's a 70mm Orion Multi-Use finder. The original objective was pretty poor so I replaced it with a 70mm F/4.5 air spaced Carton objective from Sheldon Faworski. It's much better.
At F/4.5 there's a fair amount of false color though it tends to be redder than the typical purple one sees in most scopes. One of the difficulties is that there is no focuser, it's slip-slide focusing and at F/4.5, that is pretty tricky. My first try was with the 4mm TMB Planetary for 79x and I saw elongation and a possible split, with the 6mm TMB and a 2x Barlow for 105x, I saw a clean split.
I think Porrima is at 2.85 arc-seconds, an easy split in a good 70mm with a real focuser but with this finder and no focuser, I was darn happy. It's not what one would call a double-star scope and the color was way off but I did make the split and it's the closest split I have made with this particular scope.
In light of the other threads current in this forum, What is the Best Double Star Scope and Aesthetics versus Aperture, this scope proves that any scope can be a double star scope and there are challenging, doubles for any scope.
Compared to the beautiful white pair in the 120mm, this messy red image was not aesthetically pleasing but I just making the split was beautiful.