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Tropo-Bob
09-01-2016, 12:00 PM
What features do you look for on a telescope?

Recently, I nearly become carried away and brought an extremely high quality refractor. However, the more I looked, the more concerned I became that:
1. It did not have an easy adapter to accept different red dot or optical finders.
2. It came with it own tube holder, which though highly regarded, I had no personal knowledge of how easily interchangeable it would be to immediately use on different mounts.
3. It did not have a two speed focuser.

Whilst not totally necessary, I would have also liked:

1. The ability to rotate the focuser so that it is easy to either mount the tube either underneath (as per EQ mounts) or on it side (as per many altz mounts), without have to adjust the tube rings.
2. The focuser to be graduate (to make astrophotography etc easier)
3. An easy to remove lens cap (I do not know if this is an issue with the scope I considered, but I have a fine Orion 80mm triplet with all the above features. However, my enjoyment of that scope is slightly degraded by the screw on/off lens cap which makes the scope a little more of a hassle to set up/put away.)

So what do other people look for. To me, the issue is a bit like buying cars in the old days (early 1970s), when, do U buy the powerful Australian car, or do U buy the Japanese car with the carpets and all the other nice features?

So please, give your opinions on what are desirable features on new telescopes?

glend
09-01-2016, 12:30 PM
Desireable for what? Are you only considering refractors? Focuser rotation can be a problem when imaging as it can affect the collimation due to inprecise manufacturing. Moonlight offer easy focuser collimation but It's not easy on a refractor without a good laser and target over the objectve - not something you want to do whenever you'd like to rotate - better to use the tube rings to rotate the whole thing.

Dual speed focuser, with a brake, is important to imagers.
Reconfiguring the back end for imaging may require extensions tubes and removal of diagonal.

el_draco
09-01-2016, 01:59 PM
Simple. MOUNT IS KING. Great OTA on a crap mount equals crap experience. Crap OTA on a great mount. Much better result. You can find, locate and track objects with minimal frustration and then concentrate on improving the performance of the OTA.
I would not buy less than a G11.

My thoughts.

Rom

glend
09-01-2016, 02:17 PM
So anyone who can't afford a $6000 mount is wasting their time eh?

el_draco
09-01-2016, 02:32 PM
You pay for what you get. Plenty of good mounts including G11's going around for less than $6k. The logic of my statement is sound.

If you stick a top of the range OTA on a junk mount, you'll end up frustrated as hell.
If you want to do anything other than visual, you need to be able to track accurately.

Mount is King

Simple

Chris85
09-01-2016, 03:05 PM
My $2000 azeq6 consistently pulling 30min subs with a 10" Ritchey-Chretien. Your argument, for me at least, is invalid.

KenGee
09-01-2016, 04:48 PM
Chris you're confirming his point, you would be sad, no matter how good your telescope was if your AZEQ6 wasn't working well. While I wouldn't put a number on it, I generally say to people you should spend at least as much for your mount as you do for your telescope.

Somnium
09-01-2016, 05:20 PM
when i was looking for a scope i was looking for a nice flat field with tight stars.

el_draco
09-01-2016, 05:34 PM
Exactly. Probably more, if you can afford it. If your mount has excess capacity, then the setup can grow, but a poorly performing mount working at its carrying capacity is just endless frustration.

rustigsmed
09-01-2016, 07:31 PM
sorry ken, i am struggling to understand how Chris' comment is confirming Rom's point? Rom stated he wouldn't get anything less than a G11 (a very nice, consistent mount). but yes having a good mount is the more important factor than a costly scope.

back to the OP, yes the more expensive the scope, usually the more expensive the add-ons. all scopes will generally need some kind of additional accessories which on the upper end scopes are expensive. actually even on the less expensive scopes, to make it good (especially for photographic purposes) you usually need to upgrade the focuser and apply a field corrector of some kind. for me the telescope comes down to the FOV you are after and the amount of money you have to spend on it (and the mount capacity) - taking into account the accessories that are required for it to be fully functioning.

torana68
09-01-2016, 09:36 PM
desirable features?

1. that its affordable, life is great if you don't blink at spending 20k on a hobby, that's not a requirement and fun can be had for $300 if that suits the budget.

2. that it gives enjoyable views, meaning its not a hopeless case, doesn't have to be perfect or even close to be enjoyable.

3. see number one

It can be a little like buying a car , if you want Ferrari performance don't buy a Hyundai, if you can only afford the Hyundai enjoy the ride and be happy.
Oh and astrophotography can be cheap , not long ago people took great photos with locally made mounts and film cameras :rolleyes: ......you still can......

doppler
09-01-2016, 09:45 PM
[QUOTE=Tropo-Bob;1223831]What features do you look for on a telescope?
To me, the issue is a bit like buying cars in the old days (early 1970s), when, do U buy the powerful Australian car, or do U buy the Japanese car with the carpets and all the other nice features?
QUOTE]

I guess the answer is: do you want to drive your scope (hands on out in the elements) or do you want all the best features, and let the scope drive itself all night long while you stay indoors watching tv or proccessing the telescopes efforts from the night before to get the ultimate 30 hour exposure.

ags_
18-01-2016, 10:40 AM
Re the OP
What are the desirable features on a telescope?
What features do you look for on a telescope?
No1: A telescope that you enjoy & can use often and it's easy.
Nothing else matters to me, I've spent mega $ but they have all been great fun and always ready when I want to use them.
A scope that lives in a cupboard or is hidden away is useless and will give little or no pleasure.

Cheers, Phil

graham.hobart
18-01-2016, 02:01 PM
Ease of use - easier it is more you use it, More you enjoy it.
Aims of user? wide FOV? Newts are good and cheap for this but sometimes collimation can reduce enjoyment
Refractors are easier but more expensive per inch of glass
get up and go or just stay in the garden?
As per mounts, EQ 6 et al are cheap EQ mounts but often need owner attention to maximise enjoyment- for eg woeful Alt adjusters.
End of the day (or night) if you use it and it gives you the thrill of the night sky then it's the right one for you.
Graz

rally
18-01-2016, 05:31 PM
Measurable performance specifications

What is the Strehl Ratio
Spot diagram
Longitudinal Plot - Chromatic aberration

Then (and only then) if the above is suitable - some of the more user friendly specs - what type and quality of Focus system (backlash, smoothness, adjustability, total travel, locking mechanism, gear ratio, ability to add electric focus control) rotator mechanism, balance point, dew shield design.

Trouble is - what do you know the real specs of the only really critically important issues are absent on just about every manufacturers spec sheet and replaced with superlatives and meaningless drivel !