Zhumell Tabletop Dobs Compared: Z100 vs Z114 vs Z130

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Written By: Zane Landers
Category: Learn

The Zhumell Z100, Zhumell Z114, and Zhumell Z130 make up the smaller lineup of the GSO/Zhumell Dobsonians alongside their larger free-standing 8”, 10”, 12″, and sometimes 6/16” counterparts. These telescopes, along with their equivalents from other makes and brands, are some of the top telescopes we recommend to beginners, those on a tight budget, or if you’re just looking for a simple, high-quality wide-field telescope.

Zhumell Z series tabletops (Z100, Z114, Z130)
ScopeAperture & Focal LengthOptical DesignMount TypeMax FOV*Maximum MagnificationStabilityQuality
Newtonian ReflectorAlt-Az Tabletop~200x4.5/54/5
Newtonian ReflectorAlt-Az Tabletop3.6°225x5/54/5
Newtonian ReflectorAlt-Az Tabletop2.5°250x5/54/5

Max FOV figure doesn’t account for coma and other edge-of-field aberrations

Bottom Line

The Zhumell Z100, Z114, and Z130 are all great telescopes. Of the three, the Z114 offers the best value and is our favorite, but any of these telescopes is an outstanding pick for its price range. However, if you’re considering the Z130, it might be worth considering the equal and lower-priced 130mm or 150mm tabletop Dobsonian models from Sky-Watcher, Orion, or Celestron instead. Check out our dobsonian rankings page for a deeper dive.

Optics Comparison

The Zhumell Z100, Z114, and Z130 are all Newtonian-reflecting telescopes, as are most Dobsonian telescopes. All of these telescopes use parabolic primary mirrors to provide sharp images. The Z114 and Z130 are subject to slightly better quality control than the diminutive Z100, but all can yield sharp views at the eyepiece. These telescopes are far superior to common 60mm refractors or 76mm tripod-mounted reflectors, or the shoddy beginner Newtonians that come with spherical primary mirrors or Bird-Jones optical configurations coupled to wobbly tripods.

There are certainly a handful of mass-produced telescopes with better-performing optics for their apertures than the fast Newtonians sold by Zhumell and others. However, those telescopes are specialized Maksutov-Cassegrains or high-quality refractors and cost many times more than these telescopes (as well as lacking the ability to provide wide-field vistas of deep-sky objects like these fast instruments can).

The Z100 and Z114 have a focal ratio of approximately f/4, translating to a focal length of 400mm and 450mm, respectively. The Z130 is a slower f/5 instrument. An f/4 telescope is considerably harder to focus and collimate accurately than an f/5, though the former is hardly a concern with any of these telescopes at the typically low magnifications you will use them at.

Unusually, the collimation adjustments for each of these three telescopes are a completely different process (at least for the primary mirror). The Z100’s primary mirror is essentially not adjustable without removing the entire mirror cell and tilting it with respect to the back of the tube. The Z114’s primary mirror can be adjusted by simply turning the hand knobs at the back. The Z130 requires you to remove a pointless metal plate at the back to access the collimation screws, and these screws require a Philips head screwdriver to adjust.

The collimation of all three of these telescopes’ secondary mirrors is adjusted the same way: you use a hex key to turn three screws that tip/tilt the secondary. The Z100’s secondary mirror sits on a 3-vane spider, which yields six diffraction spikes (like the James Webb Space Telescope) on bright objects; the Z114 and Z130 have 4 vanes, yielding 4 brighter spikes like the Hubble Space Telescope.

The Z100, Z114, and Z130 all use a plastic 1.25” rack-and-pinion focuser to hold your eyepieces and adjust focus. This focuser isn’t the best; it will sag and wobble with heavier oculars, though you can shim and lubricate it to compensate. But for the relatively low prices these telescopes command, it is fine. It’s possible to add an aftermarket metal focuser to any of these telescopes, but I wouldn’t consider it particularly worth doing so unless one was also upgrading to a 2” focuser. The Z130’s secondary mirror is large enough to illuminate wide-angle 2” eyepieces and a coma corrector if you did drill holes for and install an aftermarket 2” unit.

Accessories Comparison

The Z series tabletop Dobsonians all come with a broadly similar set of accessories: two eyepieces, a red dot finder, and nothing else. The Z100 and Z114 come with a 17mm Kellner and a 10mm Kellner eyepiece. The 17mm yields 24x in the Z100 and 26x in the Z114; the 10mm provides 40x in the Z100 and 45x in the Z114. The Z130 swaps the 17mm Kellner for a 25mm unit (30x) and retains the 10mm (65x in that scope).

The Kellner eyepieces provided with the Zhumell tabletop telescopes are of good quality as far as Kellners go. There’s no plastic; the bodies are all metal, and the lenses are, of course, glass with full multi-coatings. However, they lack eye guards, and the Kellner design simply doesn’t work so well below f/6-f/8 or so. The Kellner design has some edge-of-field astigmatism (in the low-power 25/17mm variant) and slight chromatic aberration in these fast scopes. Their apparent field of only about 50 degrees lacks immersion, and shorter focal lengths (such as the provided 10mm) have rather little eye relief; you have to jam your eyeball right up to the 10mm’s tiny eye lens to take in the full field of view.

Of course, the trouble is that any wide-angle eyepiece actually designed to work well at f/4 or f/5 costs around as much as any of these telescopes themselves. The longer “redline/goldline” oculars are disastrous in a fast scope, even more so than a Kellner or Plossl. For what you’re paying, the provided Kellners work fine. If you want a low-power, wide-angle view, a good Plossl or well-corrected wide-angle eyepiece in the 22–26mm range works well with any of these telescopes. We would recommend replacing the 10mm Kellner with a 9mm redline/goldline for a wider field, more eye relief, and a slight bump in magnification.

Of course, a mere 40x or even 72x is not enough power for splitting tight double stars or close-ups of the Moon and planets with even a relatively small telescope such as the Zhumell tabletop Dobsonians. The little Z100 works best around 100–140x for high power work (maximum of 200x); the Z114 performs ideally around 120-180x (maximum of 225x); and the Z130, when not limited by seeing conditions, can go up to around 250x and provide sharp views of small, bright targets. As such, a shorter focal length eyepiece, or barlow, is needed. The oft-cited 6mm redline/goldline (67x, 75x, and 108x in the Z100, Z114, and Z130, respectively) is a good start, but a ~4mm ocular such as the Astromania/BST planetary (100/113/163x) or so is more appropriate for these telescopes.

All three of these telescopes come with the dependable “StarPointer” generic red dot sight, which runs on a CR2032 battery and is entirely plastic. Its base attaches directly to the telescope with two screws; no interchangeable bracket is provided. Given the wide-field nature of these telescopes, you don’t really need anything more.

No collimation tools are included with the Zhumell tabletop Dobsonians. Due to the nature of the plastic focuser, a laser won’t be effective (and cheap lasers tend to be of poor quality anyway). Any Cheshire or a “collimation cap” will do, and in a pinch, you can collimate on a star. Check out our collimation guide for more information. The good news is that none of these telescopes tend to lose collimation very often.

Mounting Comparison

The Z series tabletop Dobsonians are, in fact, not technically Dobsonians but are in fact utilizing a design known as the one-armed alt-azimuth fork mount. This is because these telescopes pivot up-down on a bolt and ball bearing, not supported by Teflon pads and gravity like a proper Dobsonian. However, this difference is arguably irrelevant from a nomenclature perspective. These telescopes operate like any other Dob, with a convenient knob on the side to adjust the tightness of the altitude axis. They pivot in azimuth on a set of three small Nylon pads, essentially like any other Dobsonian, with optimal friction produced by the melamine surface of the base gliding on the pads.

The Zhumell tabletop Dobs’ bases come fully assembled with the telescope tube attached when they arrive in the box. However, you can take the bases apart with a pair of wrenches and a hex key to pack them flat if need be, though this may not save a lot of space.

The way in which each model attaches to its base is different. The Z100 uses a stubby Vixen-style dovetail bolted directly to the tube, which in turn slides into a saddle on its mount. The Z114 is enclosed in a plastic clamshell and the Z130 sits inside a pair of felt-lined metal tube rings, which are in turn bolted to the mount. The Z100 can technically be attached to a different mount/tripod but without rings, the eyepiece/finder can end up at odd angles. The Z114 would need both rings and a dovetail, while the Z130’s rings can be bolted to any Vixen-style dovetail to attach to a third-party mounting.

The Z100, Z114, and Z130’s mounts are all constructed primarily out of particle board with a melamine coating. This material is fragile and can be easily damaged if dropped or abused. Additionally, the dense nature of particle board means the Z130 in particular has a rather heavy base. However, this is not much of a concern, and for the price of these telescopes, there is little to complain about in the construction or operation of these telescopes and their mountings. The motions of all three of these telescopes are buttery-smooth, even at high magnifications. 

Aside from their general size and the manner in which the bases attach to the tube, the only difference across the three models is that the Z100’s base features a plastic adapter with ¼ 20 threads, so it can be directly attached to a photo tripod if you wish.

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