Quote:
Originally Posted by Wavytone
You should try again now that I've fixed the collimation. It was quite close but not quite perfect at 450X and I thought leave well enough alone. But last Saturday I broke out the screwdriver and tweaked it, ever so gently. All it took was barely crack 1 screw, perhaps 1/10th of a turn or less.
Now that it's spot on I can say a Strehl of 97% is quite something to behold, and I was quite surprised at just how much difference that tweak made at really high powers on close multiple stars and planets.
Something else also stood out looking at the moons of Jupiter and Saturn - even in poor to average seeing its quite easy to identify those that are moons and not stars. Jupiters moons are resolved nicely... Saturns are harder.
Compiling a list of close double stars to see how it fares near Dawes limit.
FWIW I have a nice 8" f/9 mirror with a fine figure in storage, never used.... I think that's going to be up for sale soon.
|
Wavy...
Collimation...Thats actually a bigger problem than most realise with SCTs and even less frequently Maksutovs
One of the main reasons otherwise good SCTs get bad raps..usually the owners fault ..some are even sold way out of collimation to the unwary, only to be cursed and resold within months..
They all screem foul about the ordinary images, and thats one bad reputation they unfairly hold ..bad images that should not be in most cases...Ive had some really good ones...Collimation and cooling is a must otherwise they will perform poorly.
PS: Wonder if Synta SW or Celestron will ever release a big Maksutov over 200mm , they had one 305mm in testing ..what happened to that!
bigjoe