Author Topic: Beginner looking for help with planetary and lunar observing telescope  (Read 745 times)

kerolero

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #15 on: January 13, 2018, 10:03:27 PM »
Before buying, you'll really be well advised to join a local club, or as another poster suggested, attend this year's NEAF since it's held fairly close to you. I have looked through a number of SCT's, and once you get above 8-inches they rapidly increase in size, weight and expense because you 'll have to pay the bucks for a mount that can handle it. It goes without saying these telescopes cost a pretty penny as well. You can get just as good a view of the moon and planets with a 6-inch or larger Dob if you don't mind the lack of tracking. You will find the F/6 or longer focal ratioDobs often are better for planetary observing than the F/5 or F/4.5 models, but even those will do well if the optics are of good quality and correctly collimated. It's easier however for opticiansto make a truly good F/7 mirror than a F/4.5 mirror. I observe the moon and planets with a 6-inch F/8 Dob, and the views are very good. When the seeing's very steady, they are even better through my 15-inch F/4.5 Dob because I can go to 425X or even higher.Themain reason Iopted for F/4.5 telescopes isafter a point telescopes just get too big to handle once you getmuch above 10 or 12-inches with focal ratios of F/7 or more.A refractor, especially an apochromatic refractor is also a very good choice, but you'll need a rather large equatorial mount yet again for it. I would take the time to check out telescopes in person, especially if you have to carry it to and from your car and set it up somewhere away from your home. Also, take into consideration how much time you have to devote to astronomy. For example f it takes you 30 minutes just to set it up, and you often only have a free hour or so to observe, you'll probably be wishing you opted for one that is quicker and easier to set up, even if it's smaller.

Taras

whoopsirode

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #16 on: January 20, 2018, 01:33:36 PM »
I am grateful for the willingness of everyone to help and advise!
I did attend my first meeting of the Albany Area Amateur Astronomists and spoke to our MiSci astronomer as well.
Star Party on Friday was cancelled-due to a lot of snow!

Definitely going to NEAF-it is only a couple of hours south from me.

And I am keeping an open mind as I learn-and considering all options.
And I am looking, looking, looking and listening to all of you-thank you

The current option I am considering is the Celestron AVX 8" with the AVX mount-but wondering if the mount is stable enough?

We have a museum sky gazing event every third Tuesday-so next Tuesday will get to see the 8" Cassegrain and 6" Dob properly set up
(but also will be taking conditions from the Clear Sky Chart into account-a great way to learn how everything comes together to impact viewing).

I am traveling to see the Total Eclipse-with just my camera (properly outfitted).

barlaliblo

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #17 on: January 21, 2018, 05:11:57 AM »
When you are at NEAF visit all of the manufacture's displays to get an idea of how portable or non-portable various telescopes can be.
At the very least Celestron, Meade and Televue will have many or all of their scopes on display and mounted. Other vendors may only have their scopes displayed on tables. Any scope can suddenly look much larger when mounted.
If you are looking at a go-to scope have someone actually demonstrate one for you.
If a scope does not give the impression of being easy to transport then avoid it. A scope that is too much to lug in and out will become a passing fancy.

Ghassan Pham

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #18 on: January 26, 2018, 02:03:59 AM »
For planetary a stable mount is necessary because you will be using high power.

For most nights seeing will limit your magnification. good nights are 200x.
Very rarely are nights stable enough to go over this.
Or course seeing is subject to your location. I live in the cloudy windy midwest.

Saying all of this, You want a scope that can handle 200x.
Tracking is nice because at 200x thing move through your eyepiece fast.

an 8" sct is a good choice, could be a computerized mount or a GEM.
an 120mm achro is ok. It will display false colors on Jupiter and the moon to some degree. should be on a gem.
120mm apo on a gem is really nice but big $$$
150mm f6 reflector on an gem. (this would be the most economical choice) You will have to use short eyepiece or a barlow.
8" dob but then you have to get good at bumping the scope. (this is very economical too)

There are a lot of good posts here, i don't know if i am adding anything here.

============
Planetary eyepieces are a consideration too.

You will be using high power and going from a 6mm to a 4mm is a huge bump up in power.
So you will have to have a lot of eyepieces to get just the right one for the night's sky.
Some people use a baader zoom eyepiece but these are big bucks.

Plossl's actually perform well for plaentary viewing, but they have really short eyerelief.
If that is a problem for you.

Volcano top ortho's I think give the best views, but the field of view is small.  no problem if you
have a motorized tracking mount. Even a gem with slow motion is acceptable. A dob ....
maybe not.

I like the TMB line of planetary eyepieces they have plossl quality with a wider field of view,
and much better eye relief.

adviconno

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #19 on: January 31, 2018, 03:41:11 AM »
Quote
I am grateful for the willingness of everyone to help and advise!
I did attend my first meeting of the Albany Area Amateur Astronomists and spoke to our MiSci astronomer as well.
Star Party on Friday was cancelled-due to a lot of snow!

Definitely going to NEAF-it is only a couple of hours south from me.

And I am keeping an open mind as I learn-and considering all options.
And I am looking, looking, looking and listening to all of you-thank you

The current option I am considering is the Celestron AVX 8" with the AVX mount-but wondering if the mount is stable enough?

We have a museum sky gazing event every third Tuesday-so next Tuesday will get to see the 8" Cassegrain and 6" Dob properly set up
(but also will be taking conditions from the Clear Sky Chart into account-a great way to learn how everything comes together to impact viewing).

I am traveling to see the Total Eclipse-with just my camera (properly outfitted).

Concerning the AVX: I've used the AVX often with a 100mm Lunt solar scope tandem mounted with my 80mm refractor, the total load is about 20 lbs. and it handles this setup well. Vibration from casual knocks into the eyepiece settle down in about a second, and wind gusts(probably up to 5 mph)do not noticeably make the mount shake.My usual planet observing setup is my 8" SCT with binoviewer (about a 15 lb. load) on a Celestron CG-5 (AVX predecessor). I more often prefer the planetary views it gives compared to my 16"Dobsonian or 80mm ED refactoreven under the best ofobserving conditions, due to the obvious aperture advantage over the 80mm and the tracking of the EQ mountcompared to trying to track manually at high powers (~300x)with the Dobsonian. I highly recommenda comfortable seat and a binoviewer for planetary viewing; being able to relax your body and use both eyes brings out a wealth detail that is missed while observing while standing, using just one eye/eyepiece.

bakhvecenle

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #20 on: January 31, 2018, 07:06:34 AM »
Thanks Justin-good advice and I appreciate it. Sounds like the set up may be one to seriously consider and look at at NEAF.

Nick Ellis

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #21 on: January 31, 2018, 08:39:34 AM »
Quote

There are lots of good choices for planetary scopes and a tracking mount can be an advantage.. But some scopes track better manually than others, some observers actually enjoy tracking manually.. the more you do it the better you get.. last night I was thinking about a similar thread, I ran my big scope up to 805x, it was stable and smooth tracking by hand.. most scopes are not that good.. but many are.

One general suggestion, the moon and planets are interesting targets but they are often not visible and when they are visible, conditions may not be favorable for their observation. Currently Jupiter is rising about sunset and is not well placed until late in the evening. Saturn rises about midnight and won't be well positioned for a few hours..Mars is very small right now. And the stability of the atmosphere s often and issue, particularly at more northly latitudes.

My point: Amateur Astronomers have to be opportunists. If your interests include binary stars and deep space objects, you will have many more opportunities to enjoy the night sky than if you stick with only lunar- planetary. Consider your purchase in the context of observing everything there is to see. This not only provides more opportunities but you will discover aspects to the night sky that you might never imagine..

There's a lot of magic out there just waiting for you to look at.

Jon

heelmiliso

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #22 on: January 31, 2018, 10:05:24 AM »
Quote
I see you're listed as being in upstate NY. If you can wait three weeks and can take a drive down to Suffern, NY (near where I-287 and I-87 part ways), I *strongly* recommend investing in a visit to NEAF. There you can talk with dozens of experts and come face-to-face with a huge variety of scopes and accessories first-hand:http://www.rocklanda...y.com/neaf.html

yeah come to NEAF.

a 6in f5 is a great scope that can work well on a alt/az mount and can acclimate well and does all you want and more.
and weighs only 8lbs 14oz.

I hate steel tubes, they create temperature issues and are so heavy, I love cardboard tubes, even a 6inf8 does well on a inexpensive ldx55 mount.




kondcongrese

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #23 on: January 31, 2018, 12:47:18 PM »
Quote
I am grateful for the willingness of everyone to help and advise!
I did attend my first meeting of the Albany Area Amateur Astronomists and spoke to our MiSci astronomer as well.
Star Party on Friday was cancelled-due to a lot of snow!

Definitely going to NEAF-it is only a couple of hours south from me.

And I am keeping an open mind as I learn-and considering all options.
And I am looking, looking, looking and listening to all of you-thank you

The current option I am considering is the Celestron AVX 8" with the AVX mount-but wondering if the mount is stable enough?

We have a museum sky gazing event every third Tuesday-so next Tuesday will get to see the 8" Cassegrain and 6" Dob properly set up
(but also will be taking conditions from the Clear Sky Chart into account-a great way to learn how everything comes together to impact viewing).

I am traveling to see the Total Eclipse-with just my camera (properly outfitted).

For visual observing the AVX mount is fine for an 8-inch SCT. If you plan to do a lot of imaging, especially long exposure imaging, the CGEM mounting would be better as you don't generally want to use muchmore than half the mounting's load capacity to assure adequate steadiness. That mounting will also handle a 9.25-inch SCT too as well as4 and 5-inch refractors. If you plan to do a lot of imaging in the future, I would get the CGEM mounting. Even the AVX mounting however can be used for imaging, if you don't throw on ten pounds of gear on the telescope then try to image during a windy night.

In another post you mentioned the view through a 10-inch Dob you looked through wasn't sharp. While it could have been due to mis-collimation, less than great optics or poorly matched eyepieces for the telescope, thereare otherfactors to consider. Those are the seeing and thermal currents in the telescope itself. One or the other, or both could easily have been the reason for what you saw. All catadioptics have one drawback you need to be aware of before purchasing one, and that is their tubes are sealed. That is a good thing when it comes to keeping the coatings on the mirrors clean andbright. It's a bad thing when you take that telescope from a warm house into the cold night air, and the tube currents will turn the view into a hopeless blur until the telescope cools down. It's not a deal breaker, but you should be aware of it. And after enough time passes to reach thermal equilibrium with the surrounding air, you might still see a blurred mess because the seeing overhead is bad. There's nothing you can do about that, except make use of that night to look at things where blurry views are not as big a problem such as nebulae and galaxies at low to medium powers. Last night with my 10-inch Dob, I found the seeing to bevery bad for the planets, but I still had nice views of the galaxies and nebulae I was observing, plus two comets in the bargain. It was steadily cooling down as the night cooled down and Jupiter looked awful at 280X. When the seeing is good, I can clearly see Titan as a tiny orange disk at 375X though the same telescope. If however, the views NEVER get better no matter how good the seeing is, there is clear evidence the problem lies in the telescope, your eyes or both. However, that is a subject for another thread.

Taras

James Bradmon

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #24 on: January 31, 2018, 01:02:18 PM »
I have always found planetary observations to be highly dependent upon conditions. The most detail and best view I have ever had of Jupiter was with my 10 inch dob. This view only occurred for a short period of time during a long observing session. Why? Because the seeing conditions stabilized for a few fleeting moments. From a hazy grainy view to Crystal clear and more detail than I've seen in any amateur photo. I'm talking about details within the small storms and much more detail throughout the bands. Burn into your mind kind of view. I mention this because you may not be able to see what a scope is really capable of without multiple sessions and some conditions luck. I've had great views of Jupiter in my 66mm as well but a different type of view. It's all about perspective and expectations too. Really great opinions above. The easier a scope is to set up the more you will use it. A 10 inch dob is not that hard to set up but the tube can be awkward to carry and should really only be moved in two pieces. SCTs are not my thing but they have lots of benefits, I also think GEMs can have a steeper learning curve for beginners as well. Don't forget needing a power source for go-to mounts. Equipment that you want(not necessarily need) to have with you during a session is going to be more than what a beginner has thought about, and all of it takes time and empty hands to carry. Remember that when considering a large scope and mount. No matter what scope you Get, an observing chair is worth its weight in gold. You will see more detail using one I promise, because you will be comfortable when those conditions get just right! Good luck, your gonna have a great time, sounds like you are doing it right with some hands on time before your purchase.

Robert Laygo

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #25 on: February 02, 2018, 01:52:56 PM »
I'll guess that your seeing is seldom different from Toronto's.... in other words poor. This probably means you're going to be working at 100-150x most of the time and occasionally 200x. In all honesty, almost any decent scope from 4" up can do this.

I'll confess to being surprised that nobody has suggested the Skywatcher 180 Maksutov Cssegrain. This is a really fine scope for high magnification, it's reasonably compact and it will be seeing limited almost every night. Saving some money on the scope might allow you to jump into binoviewing. A used Denk II will go for around $450, add a couple of pairs of eyepieces and you're ready to go.

I'll refrain from suggesting a mount because I have no experience with the AVX and similar.

PS - the best view I've ever had of the moon was with my APM 115, of Jupiter it was with my ETX105. For Mars it was with a 100 year old 7" refractor during the 2003 conjunction and for Saturn it was with my 12". The lesson - as a few have commented - seeing trumps everything.

Tony Patton

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #26 on: February 02, 2018, 03:06:59 PM »
So my husband surprised me with binoculars to start with until we decide on the telescope-Celstron SkyMaster DX 8x56.
It is an excellent way to learn about the sky!
Even though it was cloudy we could see many stars that couldn't be seen with the naked eye.
Tonight was clear and the same thing-the sky just popped with the binoculars!
We used an app to just identify some of what we were seeing-definitely on the 'manual' mode!

Would the same type of experience happen with an SCT or larger refractor telescope?

Chris Mancia

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #27 on: February 02, 2018, 06:57:10 PM »
Quote
...Would the same type of experience happen with an SCT or larger refractor telescope?

Initially, you specified an instrument that would be suitable for studying the moon and planets. It seems you're interested in a more general approach. Personally, I think this is a very good idea for a beginner.

I think the experience of looking through relatively short focal length scopes with binoviewers is very similar to having giant binoculars. I spend most of my observing using either my APM (4.5") or Tak (6") refractors at between 20x and 60x. At high power - typical of the SCT - I find it is easy to study a single object but it is very difficult to sweep through the sky on a personal voyage of exploration.

The big issue is that compared with other designs, refractors are quite expensive. I seldom recommend a scope with an aperture smaller than about 4.5 and this holds true for refractors too. It needs to have good colour correction and a good focuser. Binoviewers are not free either and they need to be fed with twice as many eyepieces... a financial black hole for many of us.

Since you're heading to NEAF - it would be good to look at the refractors too. If binoviewing interests you, a chat with Harry Siebert (Siebert Optics), Bill Dankmeyer (Earthwin Optical) and Russ Lederman (Denkmeier Optical) would be in order.

Oh yes .. a mount.An alt-az mount is almost essential for this kind of observation. Forget about goto but digital setting circles can be helpful.

All things considered, this is not something you should rush into. Since you've made contact with your local club, a visit to a star party might be the best route.

Dan Perez

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #28 on: February 03, 2018, 12:18:09 PM »
I'd seriously consider a 120-127mm apo for your stated intentions, probably the Skywatcher 120ED. It may not have the ultimate performance of other scopes mentioned above but it will be no fuss (no collimation, dew, mirror shift, cool down etc) and provide excellent views of thousands of objects. Put it on an AVX-class mount for tracking/go to and later get a manual alt-az for quick looks.

imlukaro

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Re: Beginner looking for help with planetary and lunar observing telescope
« Reply #29 on: February 08, 2018, 06:53:54 PM »
Quote
So my husband surprised me with binoculars to start with until we decide on the telescope-Celstron SkyMaster DX 8x56.
It is an excellent way to learn about the sky!
Even though it was cloudy we could see many stars that couldn't be seen with the naked eye.
Tonight was clear and the same thing-the sky just popped with the binoculars!
We used an app to just identify some of what we were seeing-definitely on the 'manual' mode!

Would the same type of experience happen with an SCT or larger refractor telescope?


Some folks find that binoculars are all they ever need or want! It really depends on what YOU want. I love binos, but only under certain conditions. That eye popping sky is best with binos. Most scopes are better for zooming in for detail. Under dark skies, the combination of binos and scope is a powerful drug...

Happy hunting Ma'am! May your skies be dark and filled with stars!

CB