Quote:
Originally posted by Starkler
I find with mine some colour is visible if I crank the power up to around 100 on Jupiters limb.
The collimation on mine is also spot on as received, and its a new thing for me to actually see an airy disc. When the seeing is good stars look like little targets with a centre dot and one ring around them.
|
Compared to your 250 mm Dob, you can get the same amount of diffraction at a third of the magnification (1/3.125) due to the smaller aperture. So the effect of atmospheric turbulence isn't as great.
That's not to say that the dob would be as good at showing diffraction rings if the atmosphere weren't present, but it does close the gap.
I haven't considered the fact that the secondary and the spiders are in the way on the dob. Too complicated.