After much research, it seems that my numbers are good and that I got a decent scope . Strehl calculates to about 93.0. I am happy with the scope so its all good.
One thing that still confuses me is that looking at a number of these ES interferometer reports, there is quite a variance in the numbers at times... All scopes from essential series to FPL-53 series seem to be diffraction limited (less than .25 PV). RMS varies quite a bit as well. I understand that sometimes you get a "good one" and there is variance, but if an essential series scope has close to the same numbers as an FPL-53 scope, is it for all intents and purposes the same?
I also assumed that the numbers would be linear, meaning that the numbers would always be better on with an FPL-53 scope over an FDC1 essentials scope (with a few VERY rare exceptions). Also, doesn't the glass make a difference as well even if the numbers are close between 2 scopes? If so, how?
My thought was always if you paid more for a scope with better glass, and the assumption that it is subject to more stringent manufacturing standards, it should always perform better than a scope that's 1/4 of the price. If I buy a 100K Mercedes, and get the worst one made, I don't expect that a Mercedes 1/4th of the price, even if its the best one made will be able to out perform me.
Maybe I'm over simplifying it, but it would seem to me that if you're going to buy a scope and especially if you're going to pay a lot of money, that you would buy used and get the report first.... I haven't seen a BAD report yet, but it seems like there is a LOT of variance between scopes.
Again, I may not be fully understanding all the variables involved, but it seems odd that someone could pay a lot less money for a scope by the same manufacturer and if they get lucky, get the same performance as a expensive scope from the same manufacturer.
Is this accurate or am I just a hopeless noob lol
Focal Length: 910 mm
Aperture OD: 100 percent
PV: 0.238 wave
RMS: 0.043 wave
Edited by SkyHunter1, 29 March 2019 - 01:54 PM.