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View Full Version here: : Cheap Planetary telescope solution? --advice anyone??!?!


overlord
27-06-2008, 08:15 PM
Hello everyone, my first post here.:D

Firstly, since i got my dob five years ago, i have been unable to see a single galaxy from my location. I once thought i saw a caught a whiff of the sombrero, if i jiggled the scope and used extreme averted vision, but that's it, so i soon turned to planatary observation.

Last night in melb seeing excellent ~midnight, used my 8" f/5 dob at 300*- (10mm + 3X barlow), pretty much the max mag for my skywatcher dob.

Whilst drawing Jupiter, I noticed uneven shadings on Jovian moons, which were barely disk size. So, I wanna magnify the moons to map the details.;) I mapped mars in 2003, and now I wanna map each moon. So I think I require at least *1500 power in some big-momma setup.
I want view to make me look do this: :scared: :scared::scared:, but if it's expensive i won't bother.

what do people use?

tnott
28-06-2008, 12:13 PM
Whatever scope you use, seeing will limit you to 300X on 95% of nights unless you live in an unusually still site(tropics?). I am limited to 210X most nights, can get 300X occasionally and have gone to 420X only once or twice. Bigger scopes will show more detail on planets in those rare moments of good seeing and more colour.

Most of the time I use my ETX 125 for planetary viewing, but the 16" scope definitely shows much more in those still moments. Bigger scopes need some form of cooling as well.

Starkler
28-06-2008, 12:22 PM
A big newtonian with quality optics. There is however a factor of diminishing returns where the mirror is so big that it cant be adequately cooled to ambient.

When seeing and thermal factors are in your favour, you will see a lot more in a 12"er than an 8. Mapping Jovian moons would be a tall order though for any earth bound telescope.