planetry scope

[maslowan]

Hi all,i know there's no one answer to this question, but here goes..  I'm looking for a scope that will give detailed views of the moon and planets(visual use) will be not too much trouble to set up(will be kept in shed in garden).I'm looking to purchase a complete scope and do not want to have to upgrade for a few years.I already have a 150mm f6 newtonian which is a good scope but i suspect i need a bit more resolving power.Any genuine advice would be welcome...ANDREW....ps  I have not mentioned a buget as i will pay what it costs..just don't tell her indoors!!! :-)UPDATE...My scope is an orion optics(pre spx)newtonian.It is collimated and the mirrors are in good codition.It is a very good all round scope,but i would expect a dedicated planetary scope (say 200mm and up) to give more detailed views-seeing permitting.Still looking for a scope!!!

[admin]

I would suggest you would be looking at a premium 4"  or larger refractor really. Newtonians will need collimating most weeks, SCT's are big and bulky and tend to be from f/10 up (yes, I know there are f/6.3 ones!) and the other more off the track designs have their own foibles. Get a decent refractor and you can flatten it out for dso's and barlow it up for planetary.



Arthur

[Knorbert]

Just as a thought, if you're looking primarily at Lunar and Planetary objects, then 6" + aperture Maksutov-Cassegrains or Maksutov-Newtonians are well worth a look - reasonably compact for the focal length, don't need collimating and are well-corrected.

There are options for 8" and 10" LXD75 from Meade (M-Ns), Skywatcher SkyMax 6" 180-PRO (M-C), or even Intes-Micro 6" or 7" tubes (M-Cs).  You can see these at Telescope House (Meade Dealer), Pulsar Optical (Skywatcher Dealer), or The Widescreen Centre (Intes Dealer).  I mention these places only because they tend to have the scopes in stock and set-up for you to see if you want to visit the stores.

I have a Meade 7" Mak-Cas that occasionally see light of day, and it is an absolutely wonderful scope for lunar and planetary work - funnily enough there is one (not mine) in LX200 form on Ebay at the moment (only £200 with no bids).  This is probably a great option to avoid new prices if it's in good condition:

http://cgi.ebay.co.uk/LX200-7-Maksutov-Cassegrain-Telescope_W0QQitemZ300337561176QQcmdZViewItemQQptZUK_Telescopes?hash=item45ed837e58&_trksid=p3286.c0.m14#ht_740wt_1161

I personally favour Mak-Cass scopes over Mak-Newts, but this is only personal preference based on the compact size of the Mak-Cass.

Cheers

Mark

[RJMLynch]

I have had several Mak-Newtonians, Intes MN56 and MN76 and an Orion (USA) MN61 (I think that was what it was called!). I was very happy with the performance of the lot on planets, particularly the MN76, but that was a lot heavier than the MN56.

The MN61 was a nice compromise of ease-of-use and aperture. While budget might not be a concern, these scopes seem to sell for bargain prices currently.

The scope which I use the most, though, is an APM 130mm f/6 which is surprisingly good on planets (not what I bought it for). It is a very compact scope, easy to carry in and out quickly when the skies clear!

Cheers, Richard.

[chrisnuttall]

okay, so you have had someone say refractor, and someone say mak cass, now you have someone saying newtonian!

The refractor and the mak cass mentioned above will have excellent contrast which is king for visual observation of planets. Since you are used to a 6" reflector i think you may be disapointed  going down to a 4" refractor, it wont get much magnification by comparison. (that's a can of worms opened) it may be as good, but i doubt it will be better than a 6" newtonian. The mak cass will be heavy, requiring a more sturdy mount which takes more effort to set up and will cost more. You may also get dew problems on the corrector plate (depending if you live in a moist area) and you may end up waiting all night for the thing to cool down. If you manage these problems well it will give amazing views, i once had an ETX125 (mak cass) which had superb optics and it would just show the enke gap on a perfect night when the rings were wide open, and i seriously considered the intes maks mentioned for my current scope but i went for something else in the end because i was worried about dew and tube cooling ( Richard, i would love to hear how these scope perform in this respect having never owned one?)

I currently have an orion spx 200 f/6 reflector with 10th wave optics and an undersized secondary mirror (they will talk to you about what you want and build you a scope to suit you at orion). They were able to use a smaller secondary without any loss of fov by positioning the focal plane very close to the tube and using no focusser extension pieces, basically optimised it for visual use since i will never attach a camera to this scope. The quality of the mirrors and the undersized secondary make for great increases in contrast. When visually observing planets you want the most contrast you can get. This scope never needs recollimating - ever - due to the very well designed mirror mount. It cools in minutes, again due to the mirror cell and integral cooling fan. for its size it is extremely light weight due to the very thin gauge aluminium tube. i can also use it for visual observing of galaxies, nebulae and globular clusters since 200mm is a reasonable aperture and the fov is still pretty good.

You can argue all day about optical theories, lenses versus mirrors etc etc, but for me the scope has to be easy to live with and deliver breath taking views, and my orion does both these very well.

I observed io and europa in mutual occultation followed by eclipse a week ago, the moons were resolved as discs with a hint of limb darkening, one red and one white. they are only just over an arc second each, and the seeing was fairly poor, i was pretty chuffed with that!

You say you want more resolvng power, that means more aperture, but i wonder if the quality and collimation of your current scope might also be a problem?
what make is it?

chris

[RJMLynch]

Perhaps something else to consider is a binoviewer.

I would certainly agree that the OO reflectors are superb, I once had stunning views of Saturn through a custom-made 1/10 wave 200mm OTA (before they introduced them as standard), a BW Optik binoviewer, and a cheap 2x (Skywatcher) Barlow lens cell screwed into the barrel of the binoviewer. You can pick-up binoviewers pretty cheaply these days, and I have found that views through any half-decent scope are much better through one.

Chris; the Mak-Newts were not too bad as far as tube-cooling time went. Not a problem at all with the MN56 after a few minutes outside, which compared very well in a side-by-side comparison with a Tak FS102 incidentally, and of course the MN76 had an internal fan which I simply left running during use. Seemed to help even after you would have expected thermal equilibration.

With the 66, if the evening looked half-promising then I left it outside for half an hour before use, inverted, with the plug in the end of the OTA removed.  I don't think it was ever clear for long enough in Chester while I had it for dewing to be a problem! They were all supplied with solid dew-shields, however.

Cheers, Richard