Advice on telescopes

  • Stargazing
  • Thread starter LightMatters
  • Start date
  • #1
I'm hoping this is ok to post here as I imagine some of you will know the answer. I like to read the insights on this forum, but generally don't believe my command of the subject matter lends itself to the discussion. That said, I enjoy the night sky and am looking to get a portable telescope with about $1,000 as my limit. Does anyone have an opinion on which would be the best on the market for that sort of ceiling?

The main objective is to see some planet features. For example, perhaps the cap of Mars. Is that possible for that price range?
 

Answers and Replies

  • #2
DaveC426913
Gold Member
19,153
2,663
That is quite a budget for one's first scope.

I strongly suggest that, prior to spending that, you join (or at least attend some meetings of) a local astronomy club. They will be able to talk to you about your needs and must-haves. You don't want to spend that kind of cash only to end of with a scope that doesn't suit your needs.

Where are you located? Is there an astronomy club conveniently nearby?

There are lots of articles online about how to choose a scope. Read a few to familiarize yourself with the variables. (portability, configuration, stability of base, eyepieces, electronics).
Here's one, but there are hundreds:
https://www.skyandtelescope.com/astronomy-equipment/how-to-choose-a-telescope/
Just get an idea of the common considerations.

Also, join an astronomy forum. Find a popular one, dedicated to astronomy, with high activity.
Here's one:
http://www.astronomyforum.net


Rule #1 about buying a scope:
Magnification is not the primary criteria! Anyone tries to sell you a scope by touting its magnifying power, run away!
The first key to a good viewing experience is aperature.
 
Last edited:
  • Like
Likes davenn, berkeman and LightMatters
  • #3
Located in Eastern Ontario, Canada. There are a few clubs here and a dark sky zone that isn't a far drive.


Thanks for the link. Just started to read it over. Portability is one of the big ones for me.
 
  • #4
DaveC426913
Gold Member
19,153
2,663
Located in Eastern Ontario, Canada. There are a few clubs here and a dark sky zone that isn't a far drive.
Yes, here's some good dark sky Northwest of Kingston - there's actually a Dark Sky Preserve I've been meaning to visit some day.

But keep in mind - if you are planet-watching, you don't really need dark skies. Planets are extremely bright. I find it is a good compromise to find a more convenient location over minimizing light pollution.

I live right on Lake Ontario, just west of Toronto, so - while the sky glow is terrible to the east - as long as I'm pointing south over the lake, I can get some good observing done on planets. A lot more than if I had to drive out-of-town every time.

One of the cool things I like to do is go out every night for a week, and plot the positions of Jupiter's Moons on graph paper, with each day as a row. Then I can draw a sine curve through them, like this:

Jupiter-Moons.png


I sketched one like this from my backyard. Was able to leave the scope set up for the whole week.

Comets and asteroids are also cool to watch over multiple nights.

And of course, some nights of stargazing will be clouded over, so doing it near home means you can just go back out the next night.


That being said, your interest in star-gazing will surely grow to include dimmer targets - so do make sure that trip is doable. Don't forget it takes time to set up and calibrate and break down again.

Here's a couple of sketches I did of Mars. On the left is what I saw; on the right is a software-simulated view of what Mars looked like at those exact dates and times. I'm pretty pleased!

pic_marssketch.jpg
 

Attachments

Last edited:
  • Like
Likes davenn and LightMatters
  • #5
russ_watters
Mentor
20,238
6,803
That said, I enjoy the night sky and am looking to get a portable telescope with about $1,000 as my limit. Does anyone have an opinion on which would be the best on the market for that sort of ceiling?

The main objective is to see some planet features. For example, perhaps the cap of Mars. Is that possible for that price range?
It's totally doable for that budget, and if you're willing to commit the funds, I'm a fan of jumping in with both feet too. Quick note though on that price range; you start to lose some bang-for-the-buck in the $600-$1200 range, as you can't grow much with a scope like that. So I'd shoot for the lower end and then in a few years (months?) if you decide you really want to get into the hobby, save-up and jump up a level.

Another reason to aim a bit lower is to leave some room for accessories and maybe a cheap camera. Here's one that is comparable to my first "real" (non K-Mart special) telescope, for cheaper than it was 15 years ago ($600 and free shipping):
https://www.telescope.com/Orion/Tel...elescope/rc/2160/pc/-1/c/1/sc/14/p/114815.uts

Several manufacturers offer similar ones (Meade and Celestron are the other major manufacturers for beginners), so you can look around a bit.

Since you are doing planetary observing, I'd probably add a 2x Barlow to that, which will get you up to (actually a touch above) the maximum useful magnification of the scope:
https://www.telescope.com/Orion/Acc...arlow-Lens/rc/2160/pc/-1/c/3/sc/41/p/8711.uts

It's actually not a perfect pairing; a 15mm eyepiece instead of the 10mm it comes with would be a better fit.

Settle in with something like that and then we can talk about cameras later...

Quick note on the observing: Right now you have 4 good planets viewable. In the next month you'll lose Venus and then shortly thereafter, Jupiter. It's rare to have that many in sight at once, so this is a good opportunity to start with a bang. One minor issue for a beginner to keep in mind though: because it is summer they are all low in the sky, so in addition to needing a good view of the horizon,
 
  • Like
Likes LightMatters and davenn
  • #6
May I suggest that rather than buying a reflecting telescope you look into a good refractor with a achromatic or apochromatic lens? Since your interested in planetary observing, a refractor will have better resolution for extended objects since reflectors produce diffraction patterns, and a compound lens prevents what's called "chromatic aberration" - the smearing of colors due to different colors being focused to different distances. You'll also need to budget some money for a "clock drive", a little gadget that compensates for the movement of the Earth. Otherwise, the object you're observing will move out of the field of view in less than a minute!
 
  • #7
russ_watters
Mentor
20,238
6,803
May I suggest that rather than buying a reflecting telescope you look into a good refractor with a achromatic or apochromatic lens? Since your interested in planetary observing, a refractor will have better resolution for extended objects since reflectors produce diffraction patterns, and a compound lens prevents what's called "chromatic aberration" - the smearing of colors due to different colors being focused to different distances. You'll also need to budget some money for a "clock drive", a little gadget that compensates for the movement of the Earth. Otherwise, the object you're observing will move out of the field of view in less than a minute!
Respectfully, while I kind of agree with the apochromatic refractor for those with a very large budget - it is unmatched in sharpness and contrast for a given aperture - it is a tough call for a beginner on a budget. A catadioptric gives a lot more "bang for the buck" in a larger aperture for the money -- and it doesn't have secondary lens support struts, so no diffraction spikes.
https://en.wikipedia.org/wiki/Catadioptric_system

...also, computerized go-to systems have gotten cheap enough that I'm not sure a clock drive is really a thing anymore. And while I recognize that learning the night sky with a manual system provides a certain reward, I think today most people would rather just look at stuff.
 
  • Like
Likes davenn
  • #8
russ_watters
Mentor
20,238
6,803
Respectfully, while I kind of agree with the apochromatic refractor for those with a very large budget...
Replying to myself separately because this may be a topic for a different thread if it turns into a discussion...

I bought a decent mid level apo last year: an Explore Scientific 127CF ($1900, OTA only). I got it partly because it was well sized for imaging the eclipse, but also because I wanted to see what the fuss is about with APOs. I use an 80mm Orion apo mostly for a guide-scope, but it had showed promise for deep-sky imaging.

My first impression was that it delivers in terms of image quality and several other usability factors; Pinpoint stars in deep-sky imaging, low thermal expansion, solid focusing, etc. But wow, is it ever nowhere near big enough! And I don't even mean by 20 or 50%, I mean like a factor of three! Deep sky images with it are smaaaal and sloooow. The sharpness is nice, but due to the size it is not an upgrade over my C11. Since I don't have $30,000 to spend on a 180mm apo, my next scope is likely to be a $5,000, 14" cat (or an entire system for $10k).
 
  • #9
You're right Russ, a catadioptric would meet the OP's demand for a compact scope.
 
  • #10
Quick note on the observing: Right now you have 4 good planets viewable. In the next month you'll lose Venus and then shortly thereafter, Jupiter. It's rare to have that many in sight at once, so this is a good opportunity to start with a bang. One minor issue for a beginner to keep in mind though: because it is summer they are all low in the sky, so in addition to needing a good view of the horizon,
I saw all four the last week in the sky and all were quite bright. I'm reasonably sure that I saw Mercury with the sunrise as well. Although I know next to nothing about telescopes besides what I'm learning right now, I do have a decent idea about where things are in the sky, which is why I would like to start at a reasonable level to get something out of it.
 
  • Like
Likes davenn and russ_watters
  • #11
It is the Kingston area that I'm talking about. It's about an hour 1/2 to maybe a couple from here. Certainly not a hard trip to make. And yes, dimmer objects are of interest too, I just haven't seen any yet.

Really liked the Mars pictures. That's quite a view.
 
  • Like
Likes davenn and russ_watters
  • #13
I know it's been awhile since this was first posted, but something russ_watters said stuck out -
russ_watters said:
and it doesn't have secondary lens support struts, so no diffraction spikes.
It's not just the struts that cause diffraction; the secondary mirror itself is in the way of the image and so causes a circular diffraction pattern for every point source. This makes any extended image less resolved and more diffuse. That's why refractors give a superior image for extended objects like planets, nebulae, or clusters.
 

Related Threads on Advice on telescopes

Replies
8
Views
3K
  • Last Post
Replies
7
Views
2K
  • Last Post
Replies
21
Views
4K
  • Last Post
Replies
14
Views
3K
Replies
21
Views
4K
Replies
9
Views
3K
Replies
7
Views
2K
  • Last Post
Replies
3
Views
1K
Replies
9
Views
4K
Replies
30
Views
6K
Top