I got the Astromania 7.5mm Planetary eyepiece. At f/8, my particular sample is very nearly the equal of a Delite. It's shockingly good for its cost. I paid about $44 including tax. I haven't tested it at lower focal ratios. I suspect it might falter at f/5.
I’ve had a few of these “clones” over the years, including the Sky-Watcher version of it.
They are in fact, very good at F5, and present a very nice view with a crisp field-stop and (in my scopes) very even illumination, but they do have the following two issues:
- Serious glare issues on bright targets
- When pushing a scope to its maximum, present a rather “mushy” view
(fuzzy diffraction spikes around bright stars)
So whilst a casual glance at a star field might present a Delite-like view, I would expect that performing a Luna comparison at the edge of the scope’s limit will provide a view that’s very much inferior to a Delite.
Edited by great_bear, 19 December 2022 - 07:12 PM.