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Zhumell Z130, I choose you! Probably.

beginner dob reflector equipment
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#1 will0wtr33

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Posted 15 January 2020 - 08:17 PM

So here it is!

After about two months of research I believe I've found my ideal first scope, the Zhumell Z130 (a 130mm aperture f/5 tabletop Dobsonian).

At first I considered the AWB OneSky (SkyWatcher Heritage 130p), but after pouring through articles, reviews, and forums I've changed my tune.

Because the OneSky is a truss style collapsible scope I've heard stray light can become an issue, as well as condensation on the secondary mirror. I know creating a shroud could help with this, but honestly it's something I would rather just not deal with. I've also heard people complain that heavier eyepieces can cause the truss rods to sag and effect collimation. I haven't heard anything good about the helical focuser included with the OneSky either. According to most of what I've read the only advantages of the OneSky seem to be the charity donation they make when one is purchased, the quality of the eyepieces, and the included collimation cap. According to a few sources the optics for both scopes are identical. I can always purchase higher quality eyepieces later on. 

I've been told by a few that I should just grab a classic 6" dob and call it a day, but the truth is I don't know that I want something that large right away. A smaller scope I'll actually lug outside or to a view site is better than a larger scope sitting in my house collecting dust. I figure if I get really into the hobby I'll save for a 10" or 12" in the future.

Afters tons of helpful advice from the wonderful members of this forum I plan on purchasing the Astro Systems light pipe/sight tube combo tool for collimation. 

I'm ready to pull the trigger, and plan on ordering this coming Friday. If anyone has any last minute advice, suggestions, or warnings PLEASE let me hear them now. I'm beyond grateful for this community and the kind helpfulness of those in it. 

 

Thanks for everything,

 

-Alex


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#2 CrazyPanda

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Posted 15 January 2020 - 08:47 PM

I've been told by a few that I should just grab a classic 6" dob and call it a day, but the truth is I don't know that I want something that large right away. A smaller scope I'll actually lug outside or to a view site is better than a larger scope sitting in my house collecting dust.

 
I agree with you completely about the Z130 vs the OneSky/Heritage 130p. I do not understand the thinking behind the design of that scope. It's so small that you save very little material/weight by having an open truss at the top instead of a solid tube. Just baffles me.
 
At any rate, one thing to consider about getting a table-top dob vs a full size dob is what you put the table-top dob on.

Yes, the scope is objectively smaller, lighter, and easier to carry, but you'll also have to potentially build and at least carry a sturdy tri-legged stool for it to sit on to bring it to a comfortable viewing height.

A full size 6" dob can sit on the ground, and then you can sit in a camping chair to look through it.

To me, portability between a table-top dob and a full sized 6" is a toss-up when you consider what you need to bring with you to put the table-top dob on.

Optically, here are some other things to consider:

 

1. The F/8 focal ratio of the 6" will be a lot more forgiving collimation-wise. You will absolutely NOT need to spend money on an astrosystems light pipe/sight tube to collimate it. You can just eyeball the secondary mirror to make sure it's centered under the focuser and that the primary mirror is fully visible, and then just do a simple star test of the collimation of the primary mirror. At MOST, a $7 colllimation cap to aid in the collimation of the secondary mirror is all you need.

 

2. The F/8 focal ratio will be a lot more forgiving on cheaper eyepieces. You can buy a cheap set of "gold lines" for $110 and all 4 will perform nicely in that scope, with relatively clean field edges.

 

3. The F/8 focal ratio will not show any coma in the field. So between this and point #2, you will have a nice clean FOV to work with. Planets will stay sharp throughout most of the field of view as they drift across it.

 

4. The extra inch of aperture will make a noticeable difference in your ability to see planetary detail. Stars and star clusters will be almost 50% brighter. All extended objects like nebulae and galaxies will be 20% larger at the same brightness, or almost 50% brighter at the same magnification as the Z130.

 

IMO, the *ultimate* beginner setup is the following:

 

1. Orion SkyQuest XT6: https://www.telescop...pe/p/102004.uts

2. This set of "gold lines": https://www.amazon.c...y/dp/B01MR78I42

3. A 32mm GSO plossl: https://agenaastro.c...l-eyepiece.html (will give you roughly the widest TFOV possible, and a bright exit pupil. Would be used as a finder eyepiece to star hop with, in conjunction with the red dot sight).

 

That will give you what I think is a more realistic taste of the hobby in terms of what a telescope is capable of showing you, without spending a fortune on it. It's kind of a "best foot forward" jump into the hobby whereby if that doesn't convince you that astronomy is interesting or rewarding, then you can reasonably conclude spending more won't change that.


Edited by CrazyPanda, 15 January 2020 - 09:01 PM.

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#3 coopman

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Posted 15 January 2020 - 08:50 PM

Do you have a sturdy table to place it on?
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#4 will0wtr33

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Posted 15 January 2020 - 10:52 PM

 
I agree with you completely about the Z130 vs the OneSky/Heritage 130p. I do not understand the thinking behind the design of that scope. It's so small that you save very little material/weight by having an open truss at the top instead of a solid tube. Just baffles me.
 
At any rate, one thing to consider about getting a table-top dob vs a full size dob is what you put the table-top dob on.

Yes, the scope is objectively smaller, lighter, and easier to carry, but you'll also have to potentially build and at least carry a sturdy tri-legged stool for it to sit on to bring it to a comfortable viewing height.

A full size 6" dob can sit on the ground, and then you can sit in a camping chair to look through it.

To me, portability between a table-top dob and a full sized 6" is a toss-up when you consider what you need to bring with you to put the table-top dob on.

Optically, here are some other things to consider:

 

1. The F/8 focal ratio of the 6" will be a lot more forgiving collimation-wise. You will absolutely NOT need to spend money on an astrosystems light pipe/sight tube to collimate it. You can just eyeball the secondary mirror to make sure it's centered under the focuser and that the primary mirror is fully visible, and then just do a simple star test of the collimation of the primary mirror. At MOST, a $7 colllimation cap to aid in the collimation of the secondary mirror is all you need.

 

2. The F/8 focal ratio will be a lot more forgiving on cheaper eyepieces. You can buy a cheap set of "gold lines" for $110 and all 4 will perform nicely in that scope, with relatively clean field edges.

 

3. The F/8 focal ratio will not show any coma in the field. So between this and point #2, you will have a nice clean FOV to work with. Planets will stay sharp throughout most of the field of view as they drift across it.

 

4. The extra inch of aperture will make a noticeable difference in your ability to see planetary detail. Stars and star clusters will be almost 50% brighter. All extended objects like nebulae and galaxies will be 20% larger at the same brightness, or almost 50% brighter at the same magnification as the Z130.

 

IMO, the *ultimate* beginner setup is the following:

 

1. Orion SkyQuest XT6: https://www.telescop...pe/p/102004.uts

2. This set of "gold lines": https://www.amazon.c...y/dp/B01MR78I42

3. A 32mm GSO plossl: https://agenaastro.c...l-eyepiece.html (will give you roughly the widest TFOV possible, and a bright exit pupil. Would be used as a finder eyepiece to star hop with, in conjunction with the red dot sight).

 

That will give you what I think is a more realistic taste of the hobby in terms of what a telescope is capable of showing you, without spending a fortune on it. It's kind of a "best foot forward" jump into the hobby whereby if that doesn't convince you that astronomy is interesting or rewarding, then you can reasonably conclude spending more won't change that.

 

Alright, so realistically I can't say I disagree with any of this. When I first started researching I was looking into the Apertura AD8, but decided to trim the budget a bit. While I do have a small stool I believe would work, it may be just as much of a pain to have to carry one more thing around with me. I've been going back and forth, and if I can get away with not buying the Light Pipe just yet I can afford a little more on the scope. 

 

Hypothetically, if I were going to get a 6" instead, it would most likely be between the Orion XT6 Plus, the Skyline 6, and the Apertura DT6. Do you know of any significant differences off the top of your head? I think the XT series optics are made by synta, while the DT6 and Skyline are GSO. Correct me if I'm wrong.

 

XT6 Plus- Tool free primary mirror collimation, rack and pinion focuser, reflex sight finder, 10mm and 25mm eyepieces, 2x Barlow, collimation cap. $319.99

 

Skyline 6- Single speed Crayford focuser, 6x30 crosshair straight finder scope, 9mm and 25mm eyepiece, collimation cap. $319.99

 

DT6- Single Speed Crayford focuser, 6x30 crosshair straight finder scope, 25mm eyepiece. $299.95

 

Now that I write it out like that I'm favoring the XT6 Plus and Skyline over the Apertura.

I'm assuming the XT6 comes with more accessories to make up for the cost of the nicer focuser on the Skyline?

I wonder how the optics stack up. I suppose I'll do some more research!



#5 CrazyPanda

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Posted 16 January 2020 - 01:21 AM

The 9mm and 10mm Plossls that come with the XT6 Plus and SkyLine 6 are going to be uncomfortable to look through. Plossls below about 12mm in focal length have very short eye relief. This is why I recommend that gold line kit. The 6mm and 9mm eyepieces that come with it are not only good focal length matches for a 6" F/8 scope, but they are much more comfortable to look through and offer a wider apparent field of view, making them more immersive.

So to me, if you're going to pay extra money for a 9mm and 10mm eyepiece, a 9mm and 10mm Plossl is not where to sink your money. I would make a similar argument with the barlow. Barlow is unnecessary (and even detrimental unless you carefully plan your focal lengths around it).

 

For the XT6 Plus, the 25mm + barlow is effectively 12.5mm, which is so close to 10mm, it makes either the 10mm or the barlow a bit redundant (this is what I mean by carefully planning eyepieces around a barlow instead of haphazardly slapping a barlow into a set of eyepieces).

 

If you got the XT6 for $270, and then just started off with the 6mm and 9mm Gold lines for an additional $70 (you can get those eyepieces for less if you shop around, just have to wait longer), you'd be at $340, and have a better spread of focal lengths to work with.

 

For the DT6, I don't see what it offers over the regular XT6, and the regular XT6 is $30 cheaper. It's a toss-up whether a 6x30 straight-through optical finder is better than a reflex sight, so I don't know if that's really an advantage.

 

Basically the reason I recommend just the plain old XT6 is because it's the cheapest way to get just the scope, leaving you the most money to get some nicer eyepieces that can give a better viewing experience.

 

All that being said, there is nothing wrong with any of the 6" dobs you listed as long as you find value in them. They're all going to be optically and mechanically similar. The SkyLine 6 and DT6 do have slightly nicer focusers though. I find crayford focusers smoother and more precise than the typical Synta rack and pinion focusers.


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#6 havasman

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Posted 16 January 2020 - 02:46 AM

Will0wtr33 hi and welcome to the forums!

 

I owned a OneSky for a few years. It was an enjoyable scope, easy to use with very surprisingly good optics. The 130mm f5 class of tabletop Dobs are considerably more capable than I anticipated when I bought that one to tag along with my 16" f4.49 Starmaster. The top model in that class is the Z130. It was not available when I got my OneSky. The biggest advantage may be the solid tube but it also may be the tube rings that allow rotating the tube during a session.

 

"Perfect" collimation is a baseline requirement for a Newtonian system and I like your choice of gear, not outrageous cost and high precision.

 

http://www.eyesonthe...eTripod2x4.aspx

Links to a very simple DIY tripod. I built a version and used it quite successfully.

 

The 130mm F5 is a very fine widefield scope. One night at the club dark site we had an event encouraging newbs to get up there to observe along with some more experienced folks. I asked a group if they'd like to see 3 bright galaxies in a field. All said yes and one family of three came back out of their tent to take advantage. They all went over to the big scope and I said, "Oh no. That one can't do it. but the little one will." Then I showed them a really good M31/32/110 with an ES68 24mm and the OneSky. That eyepiece and an ES82 4.7mm make a very complete high performance kit if your skies will support the magnification of the 4.7. If not, the ES82 6.7mm is the next best choice. Those 2 will outperform a sack full of meh eyepieces every time.

 

I think you're in for a fun time.


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#7 Don H

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Posted 16 January 2020 - 01:56 PM

Do you live under relatively dark skies? If so, I think you will be pleasantly surprised by all you can see with a 130mm. I have a 114mm and my sky is pretty dark. The small scope is my choice for grab and go. It provides wonderful wide field views, which like havasman said, my larger scopes just cannot do. The details the 114 provides on brighter galaxies, nebulae and clusters goes far beyond what I would expect. I put the scope on a Versago mount and can carry it outside with a couple of eyepeices and observe right away. I think your 130 will do even better, especially on planets. If you get the 5", then later you can skip the 6 or 8 and go to a 10" for your next scope.

 

 

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#8 Volvonium

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Posted 16 January 2020 - 02:39 PM

The Zhumell Z130 is a fantastic telescope that puts up solid views because it has a good parabolic mirror.  I agree with your research that a helical screw focuser is not ideal.  The Zhumell uses a nicer focuser.  At f/5 fine focus at high magnifications will be tricky, but doable, especially if you do an easy DIY modification like using a large diameter focuser knob.

 

I like that the Z130 comes with tube rings so that it can be used with a dovetail on a traditional tripod mount.   I use my 130mm f/5 with tube rings often as a grab and go with an alt-az tripod mount (old school Vixen Polaris).  You can see a lot with a good parabolic 130mm even under light pollution.  Just be forewarned, aperture fever is real and if astronomy hooks you, you will be moving up to larger apertures.  I went up the aperture ladder pretty fast but still keep my 130mm reflector, as it's a fantastic grab and go.  


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#9 KidOrion

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Posted 16 January 2020 - 02:53 PM

PHO-O-TONS--GOTTA CATCH 'EM ALL!


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#10 Nexxsys

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Posted 16 January 2020 - 04:57 PM

Joining this thread as my first post to these forums. I am strongly looking at the Z130 as well will0wtr33 as a grab n go scope to start my stargazing journey.  So I am always excited to see posts about the Zhumell TableTop Scopes. 

 

For me it is about portability, ease of use, and ability to purchase without a hefty delivery charge (being I am in Canada).


Edited by Nexxsys, 16 January 2020 - 05:10 PM.

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#11 SteveG

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Posted 17 January 2020 - 01:12 AM

I too am a huge fan of these new 5” f5 reflectors. I have the OneSky, and I actually need the truss design, because I transport mine as baggage when I fly on vacation. I mount mine on a Vixen Porta mount, so I’m not currently using the stock base.

If you don’t need the collapsing tube, then absolutely get the Z130. I’m actually thinking about getting one myself, but I’m waiting for Skywatcher to bring this scope to the US (it’s in the works):

https://www.firstlig...30p-ds-ota.html


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#12 will0wtr33

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Posted 17 January 2020 - 01:29 AM

I too am a huge fan of these new 5” f5 reflectors. I have the OneSky, and I actually need the truss design, because I transport mine as baggage when I fly on vacation. I mount mine on a Vixen Porta mount, so I’m not currently using the stock base.

If you don’t need the collapsing tube, then absolutely get the Z130. I’m actually thinking about getting one myself, but I’m waiting for Skywatcher to bring this scope to the US (it’s in the works):

https://www.firstlig...30p-ds-ota.html

Oh wow! 130mm aperture f/5 with a 2" focuser. That is something I haven't seen yet. What a beauty. I'm still a super noob so I may be way off here, but doesn't a 2" focuser generally mean a larger secondary mirror? I wonder what kind of light obstruction the secondary causes in that scope. 



#13 havasman

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Posted 17 January 2020 - 01:55 AM

The diff in Central Obstruction will be insignificant compared to the advantage in field dimensions gained via 2" eyepieces' larger field stop. Yes, taking good advantage of the 2" focuser means a larger CO to illuminate the larger field stops. People worry way too much about CO's in standard scope packages. Folks like Zhumell sell packages that work.

 

Total Field of View = (eyepiece field stop diameter X scope focal length) / 57.3

 

Much can be learned @ CO choices here  -  http://www.bbastrode...om/diagonal.htm

And there is A LOT of other info in other parts of that website Mel Bartels has put together.

 

Most eyepiece field stop diameters can be found here  -  https://www.cloudyni...-buyers-guide/ 



#14 SteveG

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Posted 19 January 2020 - 12:02 AM

Oh wow! 130mm aperture f/5 with a 2" focuser. That is something I haven't seen yet. What a beauty. I'm still a super noob so I may be way off here, but doesn't a 2" focuser generally mean a larger secondary mirror? I wonder what kind of light obstruction the secondary causes in that scope. 

As Dick said don't worry about the larger size of the secondary. There is one thing though, due to the imaging purpose of this scope, for visual you will probably need to use an eyepiece extension for some if not all eyepieces to come to focus.



#15 Binojunky

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Posted 19 January 2020 - 01:36 PM

I have had all three at one time,still have the Meade Lightbridge 130 and the Zhumell, got rid of the Heritage  mainly because of the horrid (IMHO) helical focuser, the Zhumell is nice because of the rings, easy to balance and position the focuser, drawbacks are mainly the bulk and weight over the other two.D.



#16 SteveG

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Posted 19 January 2020 - 04:33 PM

I have had all three at one time,still have the Meade Lightbridge 130 and the Zhumell, got rid of the Heritage  mainly because of the horrid (IMHO) helical focuser, the Zhumell is nice because of the rings, easy to balance and position the focuser, drawbacks are mainly the bulk and weight over the other two.D.

 

Funny, I’ve never had an issue with the helical focuser. I think it’s because of the eyepieces I use. They all come to focus at about midway up, and the focuser threads are nice and tight at that location. Additionally I used heavy grease on the threads, which snugged up the focuser and turning it is exceptionally smooth. I’ve found if I use a different eyepiece and have to raise the focuser up a bunch to achieve focus, it isn’t as good.



#17 Dennis Tap

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Posted 19 January 2020 - 05:49 PM

I have the Meade Lightbridge mini 130mm F/5. Comparable to yours. It's a simple lightweight telescope, but quite capable. An ideal grab-and-go scope.



#18 belgrade

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Posted 19 January 2020 - 07:47 PM

So here it is!
After about two months of research I believe I've found my ideal first scope, the Zhumell Z130 (a 130mm aperture f/5 tabletop Dobsonian).
At first I considered the AWB OneSky (SkyWatcher Heritage 130p), but after pouring through articles, reviews, and forums I've changed my tune.
Because the OneSky is a truss style collapsible scope I've heard stray light can become an issue, as well as condensation on the secondary mirror. I know creating a shroud could help with this, but honestly it's something I would rather just not deal with. I've also heard people complain that heavier eyepieces can cause the truss rods to sag and effect collimation. I haven't heard anything good about the helical focuser included with the OneSky either. According to most of what I've read the only advantages of the OneSky seem to be the charity donation they make when one is purchased, the quality of the eyepieces, and the included collimation cap. According to a few sources the optics for both scopes are identical. I can always purchase higher quality eyepieces later on.
I've been told by a few that I should just grab a classic 6" dob and call it a day, but the truth is I don't know that I want something that large right away. A smaller scope I'll actually lug outside or to a view site is better than a larger scope sitting in my house collecting dust. I figure if I get really into the hobby I'll save for a 10" or 12" in the future.
Afters tons of helpful advice from the wonderful members of this forum I plan on purchasing the Astro Systems light pipe/sight tube combo tool for collimation.
I'm ready to pull the trigger, and plan on ordering this coming Friday. If anyone has any last minute advice, suggestions, or warnings PLEASE let me hear them now. I'm beyond grateful for this community and the kind helpfulness of those in it.

Thanks for everything,

-Alex


I must add that I think you’d love Celestron Omni XLT 150 OTA - if you have a mount with a tripod for it or you can afford/save for it. I use Vixen Porta II but there are others that would work because OTA is light. It’s a fantastic reflector. Just an idea.

#19 PeterAB

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Posted 20 January 2020 - 09:53 AM

Hi,

 

I like that my AWB Onesky folds down.   It fits in the car full of travel/adventure equipment well.   It stays in collimation and the focus arrangement is adequate with medium sized eyepieces for visual observing.    

 

That being said,  I miss having the finder mounting shoe and telescope mounting rings that the Zhumell comes with.   It will be easier to add a finder with magnification and a equatorial mount with the Zhumell.

 

If the folded down size is not an advantage for you, go for a scope that doesn't fold.

 

Enjoy the views,

 

Peter



#20 vdog

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Posted 20 January 2020 - 10:29 AM

The Zhumell Z130 has a lot going for it.  The only potential downside is finding something to put it on.  The mount is heavy for a scope of this size and has a wide triangular base.   This makes for a stable mount, but little stands you can put other tabletop dobs on won't suffice.  A short, sturdy, circular outdoor table works best.

 

Of course, you can just take it off the dob base and use the included tube rings to put it on a tripod.  Investing in a decent mount wouldn't be the worst idea.


Edited by vdog, 20 January 2020 - 10:33 AM.


#21 rhetfield

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Posted 20 January 2020 - 01:04 PM

Another advantage of the truss design:  When doing astrophotography, the camera often needs the focal point further back than can be achieved with the focuser.  On a solid tube, the solution is an extender or a barlow.  On a collapsible truss like the Onesky, one can partially collapse the truss and end up with better pictures.




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