Quote:
Originally Posted by expon
Thanks Malcolm
How would you suggest that quality of the optics affects things? Would a premium brand 80mm be better than say a skywatcher 90mm? A significant difference?
|
A telescope with premium optics will definitely be an advantage. The optical design is also important and a telescope designed to give colour free images (i.e. all colours focus very closely together) whether it be an APO triplet or ED doublet is will provide much better views especially at higher powers. Such telescopes will out perform any short achromatic refractor under f15 (and perhaps over). Of course the telescope too has to be made by a reputable dealer and preferably hand crafted or at least be hand inspected during any quality control process. (Tele Vue comes to mind here)
Collimation too is critical for a good image with any telescope and most refractors need no tweaking whereas Newtonian reflectors need to be checked often.
If you are considering a DOB you can get a Poncet Platform to enable tracking for up to 1 hour before having to reset the base (a mechanical function). Search the web for Poncet Platform and you will get some images. Such a platform provides EQ movement not Alt-Az movement and therefore you wont have the field rotation issue provided your platform is built to the right latitude.
See
http://www.equatorialplatforms.com/ for platforms by Tom Osypowski.
Having an image that does not move is a definite advantage as one can then concentrate on seeing subtle detail and such detail is then much easier to see since you are not shifting your attention on a moving object. This is as much true for observing planets as it is for observing faint galaxies.
Note too you want a solid and stable mount/platform as any wobble of the tube on its mount during observing can also take your concentration away from the object especially at high powers.