Was another post that 30x per Inch in reflectors, and 50x per inch in refractors.
Tho I go for what I'm seeing per given night, above numbers seem about correct. My 65mm Swift achro refractor over f/10 certainly the above released refractor 50x per inch and then some at over 135x easily. My current XT10 using on Mars seems to match the 30x per Inch tho on excellent sky.
There is another factor not mentioned is an extremely rare Steady Sky, only witnessed this marvelous condition 3 times in my 6 decades of Viewing! Like focusing clearly on a fence post, unbelieveable! My Xt8 then used happened at work in parking lot able to share the View! So many markings on Mars difficult to label the features, Awesome! Power here barlowed 4.8 Televue well over 400x and image Held!
Your scopes must be aligned or you'll miss these amazing Mars features, and it rises so high fantastic possibilities.
Just Now My first view in way to many cloudy days just after midnite was a clearly lined SPC Polar Cap tho tiny now, and Mare Sirenum was well shaped, great at modest over 170x 7mm Pentax, but even better at 200x takahashi ortho 6mm. Rarely hit 300x as needs best sky, but enjoyed several.
If you enjoy just low power views your limiting catching the finer features, but that' just my 6 decades experience.
Hope everyone eventually is treated to the rarest steady sky, Unforgettable!
Note on even average sky be patient at the eyepiece, venture then are flashes of clarity but must be at the eyepiece to catch. Are serious observors out here as caught posts those looking consistently over 1 1/2 hours, persistence required and pays off, I bow to these observors, well Done!
Edited by phillip, 28 October 2020 - 06:53 AM.