At a recent star party I attended, 2 weeks back in PA, I had both my Sharpstar 140mm PH, a dual-ED f/6.5 triplet, and my Mewlon 180c. I had 2 wonderful nights under the stars in a yellow/green zone area, each night being similar in clarity and seeing - the 2nd maybe a tad worse than the 1st with some intermittent light haze/vapor passing through.
Unfortunately I did not use them side by side - I only brought a single saddle alt-az mount - using the 140 on the 1st night and the 180c on the 2nd. I wanted to spend as much time as possible with each scope on each night in a relaxed way. Also, the optical trains were not entirely the same - though using the same line of EPs (Baader Morpheus) with both, the 140 was used with a 2" AP MaxBright diagonal with the 9mm, 12.5mm and 14mm Morpheus EPs and the 180 was used with a Baader T2 1.25" 32mm prism diagonal and the 17.5mm and 14mm Morpheus EPs.
The planetary views of Jupiter and Saturn were very good with each scope. But I would give the nod to the Sharpstar - the clarity and detail especially on Saturn late in the evening after 3-4 hours of cooling, where very sharp.
Looking at M22 and M13 in each was also a thrill as no averted vision required. On the first night, I remember being wow'ed by the 140 when viewing these two globs - I felt like I was seeing fairly deeply into each. On the 2nd night with the 180c, well it blew me away on these 2 globs - the images were much brighter with greater detail and a definite sense that I was going deeper in each vs. the 140.
I wished I could have stayed up each night to catch Orion - but I was not able. That comparison will have to wait another month or two. Anyways, that was my take away from two nights of wonderful casual observing ... and that the Mewlon 180c was not outgunned by a 5.5" APO... at least to my eyes and sensibilities.
YMMV ... clear skies!
Edited by Brollen, 22 September 2021 - 02:53 PM.