Author Topic: Talked myself out of a big scope, how about this little one?  (Read 471 times)

stalafovkith

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Re: Talked myself out of a big scope, how about this little one?
« Reply #30 on: January 23, 2018, 05:43:29 PM »
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If you want to go with a 130mm scope, there's really only one that meets your criteria.https://www.astronom...els2rl8f02pc437The AWB 130mm reflector. I don't know that it's a 'backpack' scope, but it's easily transportable, sits on a table top, or you can get a stool to set it on. Plus, it's a great deal for the money.
There are three one-arm tabletop 130-mm f/5 Dobs: the AWB OneSky (SkyWatcher outside the U.S.), the Meade Mini, and the Zhumell 130. They're all essentially the same price, all great deals, and each has its advantages and disadvantages.The OneSky has a collapsible tube, which makes it more portable for some purposes, but also means you need to build a shroud to block excess light -- unless you observe entirely at dark sites. The shroud can be built for a few dollars in fifteen minutes. This is the only one of the three that comes with a collimation tool -- an absolute necessity that you otherwise need to buy.The Meade Mini is the lightest of the bunch, and the base has the smallest footprint, meaning that it fits on a small stool. It's also the wobbliest of the bunch, though not unacceptably so as far as I'm concerned.The Z130 is by far the biggest and heaviest of the bunch. Very solid. The tube attaches with a standard dovetail, so it can be placed on almost any commercial mount if you so desire. It's also rotatable, which is a significant plus.

John Weiland

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Re: Talked myself out of a big scope, how about this little one?
« Reply #31 on: January 25, 2018, 03:29:24 PM »
Interesting side distraction, semi local there is a Meade ETX90EC, and I know I had sorta ruled the ETX's out, but the asking price is only 250 (20 day old ad) and I noticed that it has a focal length of 1250. I didn't realize with just 10mm more aperture the focal length was so much longer on the 90 than the 80.

I think this one is the last EMC model before they added the UHTC and it comes with an autostar controller in addition to the stock stuff which makes it a pretty decent deal i think. This version has no tripod though, just table top so I would probably have to buy the specific tripod for it which is kinda pricey I think.
Maybe this would be a choice to consider though.

Darius Swick

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Re: Talked myself out of a big scope, how about this little one?
« Reply #32 on: January 25, 2018, 07:38:19 PM »
A lot of people are sorry they didn't hang on to their
80mm/F5 .... they can be a lot of fun, and are very easy to handle.

I take it out at the same time as the longer higher-power scope.
Set up Jupiter or a cluster in it for family to look at, then go for smaller things.

Many also use an F5/80mm as a finder for a big reflector.

Little to lose, and not junk.....enjoy!

blacosticna

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Re: Talked myself out of a big scope, how about this little one?
« Reply #33 on: January 25, 2018, 10:20:39 PM »
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Interesting side distraction, semi local there is a Meade ETX90EC, and I know I had sorta ruled the ETX's out, but the asking price is only 250 (20 day old ad) and I noticed that it has a focal length of 1250. I didn't realize with just 10mm more aperture the focal length was so much longer on the 90 than the 80.

I think this one is the last EMC model before they added the UHTC and it comes with an autostar controller in addition to the stock stuff which makes it a pretty decent deal i think. This version has no tripod though, just table top so I would probably have to buy the specific tripod for it which is kinda pricey I think.
Maybe this would be a choice to consider though.


The 90mm is a Maksutov. It's a totally different optical beast. I also found them to be better built mechanically, but let's not get too excited...

tevezito

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Re: Talked myself out of a big scope, how about this little one?
« Reply #34 on: January 30, 2018, 01:19:46 AM »
Quote
Interesting side distraction, semi local there is a Meade ETX90EC, and I know I had sorta ruled the ETX's out, but the asking price is only 250 (20 day old ad) and I noticed that it has a focal length of 1250. I didn't realize with just 10mm more aperture the focal length was so much longer on the 90 than the 80.

I think this one is the last EMC model before they added the UHTC and it comes with an autostar controller in addition to the stock stuff which makes it a pretty decent deal i think. This version has no tripod though, just table top so I would probably have to buy the specific tripod for it which is kinda pricey I think.
Maybe this would be a choice to consider though.

The ETX80 is a short, fast refractor...https://starizona.co...actor_scope.jpg

...the light-path straight, simple.

The ETX90 is a long-focus Maksutov-Cassegrain... https://starizona.co...kcass_scope.jpg

Note how the light-path zig-zags, hence the longer the focal-length.

Here it is with a tripod, and a case even...https://www.bhphotov...d}&A=details&Q=

kocewaffre

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Re: Talked myself out of a big scope, how about this little one?
« Reply #35 on: January 31, 2018, 12:52:20 AM »
I'm sure Alan will be along to explain why you shouldn't buy a 90mm Mak-Cass shortly.  SEE! He beat me to it!

The Mak-Cass is a catadioptric design, that means it uses lenses and mirrors. Alan (Sky Muse) will tell you that it's dark, dark, dark on spacial objects, and I'm not in a position to say otherwise. I had a nice 127mm Mak-Cass from Orion that I really enjoyed, except for the tripod and mount, but that was a long time ago.

This is what I had, and while for me, it was a nice telescope, I was also a dead noob beginner. It has a shorter focal length than other 127mm designs, like the ETX 125, meaning the focal ratio was lower, brighter objects.

http://www.telescope...c/14/p/9826.uts

It's all around a lighter design, but that presents it's own issues. If something like this interests you, however, I would recommend the OTA (Optical Tube Assembly) and something like this for a mount. It's better than the mount that comes in the kit, but obviously increases your cost as well.

http://www.telescope...c/34/p/9829.uts

http://www.telescope...c/14/p/9825.uts

But, then you could buy this combo for less money.

http://www.highpoint...telescope-11084

But, if you're going to buy that Celestron, you might as well buy a GoTo SCT for $20 more.

http://www.highpoint...telescope-11036Yeah, I know, this is all well beyond your budget. Sorry, I get carried away. There ARE a lot of nice telescopes for beginners or those who want a little more portability, for under $750.

brodsandbacksosp

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Re: Talked myself out of a big scope, how about this little one?
« Reply #36 on: January 31, 2018, 10:13:14 AM »
When selecting a Maksutov, the 5"(127mm) is the minimum to consider really, the sweet-spot; not too small, not too large, just right, and with enough aperture to make owning and operating one worth the while.

I was able to zero in on Saturn one night last year with a Celestron C90mm Maksutov, on my manual Voyager I alt-azimuth, with a 6mm orthoscopic inserted, and for a power of 208x. Under my green to slightly-orange observing zone, Saturn was not so dim as to be unrecognisable. It wasn't sharp, middling actually, yet I knew right then and there that I wanted a 5" someday.

A 90mm Maksutov would simulate a 70mm f/13 refractor like this...

https://www.bhphotov...d}&Q=&A=details

A 127mm Maksutov...a 4" f/15 refractor like this...

http://www.company7...._side362650.jpg

...but in a far smaller and compact optical-tube.

A 90mm would need darker skies to observe a wider range of objects satisfactorily. In light-polluted zones, only the brighter and brightest objects would present themselves satisfactorily.

The Celestron C5 is an option as well; just the OTA, a shorter focal-length per its aperture, more expensive, weighs only 6 lbs., but with a larger secondary obstruction; yet fits a niche for some...

https://www.bhphotov...d}&Q=&A=details

Optically, however, I would not think it to be the equal of a 5" Maksutov.

Jeff Ramirez

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Re: Talked myself out of a big scope, how about this little one?
« Reply #37 on: January 31, 2018, 10:50:18 AM »
On the ETX Maksutov types, there are two varieties that work really well - the ETX105 (EC) and the ETX125 PE. These had aluminium forks with ball bearing altitude axes. The others had plastic forks / plastic bushes and don't work as well. You would want the Autostar model 497 with it.

The '105 is relatively scarce but they pop up occasionally at around $300-$350. I've owned one from new. Mine is a fine scope that has has flown many, many miles with me.

telschronexic

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Re: Talked myself out of a big scope, how about this little one?
« Reply #38 on: February 04, 2018, 10:09:02 AM »
An awesome setup would be a Celestron C6 SCT (6" aperture) on a manual alt-az mount. I used an Astrotech Voyager with great success, but others would work.

My C6 was amazingly sharp, rendered very nice images of really everything, and was wonderfully compact and light. Put a Telrad finder on it and it is so easy to point it at targets. The f/10 focal ratio means that it's easy on eyepieces, too.

I think I paid about $300 for the C6 and $200 for the mount, both used.

I have very fond memories of that setup. I sold it when I started doing astrophotography and have missed it ever since. I can't say that about most of the telescopes I have owned.

plethenofin

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Re: Talked myself out of a big scope, how about this little one?
« Reply #39 on: February 09, 2018, 04:13:18 AM »
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So for reasons that are not worth getting deeply into, at least for the moment I have talked myself out of a big scope mainly because its not worth the money for as little as I would be able to use it at this time in my life (1 and 2 year old kids for one thing).

SO

I have decided to try and find a decent small scope that still can see a lot. I understand that decent and small to most of you means big $$, but I am looking mainly just for something that can see enough to stay interesting long term and complement a larger scope rather than just being a throw away somewhere down the road.

I am considering going to look at a Meade ETX-80AT-BB that is used for $150. They seem to have decent reviews for a scope of that class but there seem to be several versions and several generations of them so its hard to tell exactly what this one all is and which ones people are talking about in forum posts. Long term durability of anything electronic with electric motors always makes me nervous.

What would be your opinions on this purchase (both the scope choice and the price) and if its a go what specifics would I be looking at when inspecting it and probably testing it as I may end up driving there after dark to look at it (hopefully).

My available choices are somewhat limited as I can only afford used stuff or such low quality stuff that I wouldn't want it. A full manual scope would also be an option if a good one came up cheap.

I bought this scope for around $200 NEW. Its comes with everything you need to start observing right away. I can carry it outside and set it up in 30 seconds with one hand ! It gives nice planetary and lunar views and not bad on brighter deep space stuff !

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incojukam

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Re: Talked myself out of a big scope, how about this little one?
« Reply #40 on: February 09, 2018, 05:19:14 AM »
I have a ETX80 and will share my opinion on this scope:

To be honest I started out with a newton 6” f5 on a gem and that scope might be the scope I have used the most at all times,
even after getting better scopes down the line.

I will not recommend the ETX 80, especially not as the first/only scope to own.
The ETX80 is a very short refractor and it does indeed have a problem with a lot of color (chromatic aberration)
this means that subjects with a good amount of light will not be pleasantly presented in this scope.
Now because of the relative small objective 80mm it won’t gather too much light ether meaning faint deepsky objects will be out of reach
even though it does have the ability to show a relative wide view.
Also the mechanics on this scope and it has a few (a inbuilt barlov, a flip mirror, and a very odd focuser)
Are rater flimsy and has got a tendency to break (look for the amount of diy presented at http://www.weasner.c...aq.html#update )
In all fairness it is a small cheap goto scope and the goto will work if you are willing to put in the labor to make it. But related to this it’s worth mentioning
that this mount and scope does not lent itself well to manual control, it got no physical handles and no finder.

In my opinion the ETX80 is more of a fun hobby tinkering project than a tool to see the sky.
(I’m not talking about the ETX90 and the ETX125 these are different scopes btw)

My ETX80 notes:
"Meade ETX 80" info:
Focal Length 400mm, Focal Ratio f/5
Acclaimed Maximum Practical Visual Power 275X ( Obs!!! prolly terestial daylight :| Spotting scope like)
400 mm / 4,5 mm +3x barlow = 266,67x (not likely)


Soo:
Magnification = 400 mm / 9 mm Eyepiece
Magnification = 44,44x - a solid magnification
+ 2x barlow = 88,88x imo. max
and
Magnification = 400 mm / 20 mm Eyepiece -
Magnification = 20x
+ 2x barlow = 40x
also
Magnification = 400 mm / 26 mm Eyepiece
Magnification = 15,38x - a nice view
+ 2x barlow = 30,77x


gl
-Gert