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Zhumell Z10 Dobsonian
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Why I chose Zhumell
I looked at Meade, Sky Watcher and Orion dobs and carefully weighed all the options. Seeing as they are all either Synta or GSO made, they should offer similar optics and after reading many forums and reviews on the subject, that seemed to be the case. The pricing is similar between the above mentioned brands so what do you get from Zhumell that you don’t get from the competition? A 2 speed crayford focuser, a wide field 2” EP, a laser collimator, a 50mm RACI finder and cooling fan standard. Some of the other brands give you some of those features, but no one offers all of them except Zhumell. At under $600 shipped, it’s a bargain.
The OTA came in one box, and the base came in a second box. Both
were single boxed, and all the contents survived without a scratch.
Everything was well packed, and I was impressed overall with
Zhumell’s packing job.
The instructions were pretty worthless, but a quick look at the parts and a glance at a picture of the finished product only required a little common sense to put it together. Assembly of the base brought back memories of putting together Ikea furniture. It’s cheap particle board laminated with a solid black veneer that’s a little heavy, but it works. The OTA only needed the bearings to be installed, attach the finder and you’re good to go. It took about 30 minutes from start to finish. All you need is a screwdriver and the supplied allen wrench.
Complete Scope! (+Telrad)
New Bearings: This is my first dob, but I like the bearings. The OTA drops in nicely to the base and the bearings give you something to hold onto when carrying the OTA. They feel well made and allow smooth movements. The base motions are smooth as well. Overall movements are better than I had anticipated. The scope needs counter weights to balance when pointed towards the horizon, but anything higher than around 45 degrees, it works great. I think this will easily be fixed with a few magnets. No big deal.
Fit and Finish: Overall, I am pleased. The base is nothing special, but the paint on the OTA looks nice and the optics were 100% clean and dust free. All of the accessories are decent quality and comparable to other major manufacturer’s products. There are no obvious flaws that I can find.
Included Items: The 2” 30mm 68 degree EP included is quite a step up from the 25mm plossl included with most other dobs. Yes, it does feel cheap and the views are soft around the edges of the FOV, but the coatings look good and the views are decent in the center. It’s quite comfortable to look through and I would prefer it to a plossl for most DSO’s. This is a sub-$100 SWA EP in an F5 scope, so don’t expect Panoptic performance, but I’m keeping it anyways.
The Laser Collimator (with a set of extra batteries!) is a nice touch too. The laser beam was centered from the factory so I didn’t have to adjust it. It worked great out of the box. Surprisingly, the optics were only a little out of collimation. Was Fed Ex actually nice to a telescope for once? I consider myself lucky. It only took a few minutes to achieve perfect collimation and the primary mirror is centered marked as to be expected.
8x50 RACI Finder: This is a lifesaver. It’s great to have a finder that actually matches star charts and doesn’t require you to have to put the side of your face against a cold OTA. I can’t seem to figure out why some folks are still putting a straight through finder on a dob. It makes no sense to me. The finder combined with a Telrad (and some good charts) is a wonderful combination that makes finding targets easy. Alignment was easy and stars are tack sharp.
So far, the optics have exceeded my expectations, but I have not done a direct side-by-side comparison with other dobs. It’s great to have so much light gathering power compared to the scopes I’ve had in the past and that’s where the Z10 really excels. DSO’s that were once faint smudges only seen with averted vision jump out like never before. This thing pulls in A LOT of light. There’s no substitute for size. Views are little soft near the edges with the 30mm included EP, but I’m blaming the EP, not the scope. The detail on the moon and Saturn is incredible. At 208x using a 12mm University Optics HD ortho and a 2x barlow, I could see no noticeable breakdown of image quality and was sharp to the edge of FOV. It can challenging to track at 200x, but with a little practice it can be done. I will probably use my 102ED on my go-to mount for most planetary observation, but mostly for the convenience, not because the views are better. Overall, the views are awesome.
The Bad (and not bad, but worth considering):
There are a few issues, but most dob owners seem to “improve” their scope’s functionality with a few modifications no matter what kind it is. The Z10 is no exception and could benefit from a few minor tweaks. These are only my initial reactions and surely experienced dob owners can think of many more beneficial mods. This is more intended for the average user (like me) who wants to use it out of the box.
1) The screws/springs that adjust the primary mirror are a little small. The secondary mirror holds collimation well, but the primary does not. Luckily, it only takes a few minutes to adjust, but needs to be done each observing session. Many do this anyways, but stronger springs would be a good and inexpensive upgrade.
2) The OTA needs balancing help when viewing low targets and/or using heavy EP’s. It’s a dob…what else is new right?
3) The lens cap sucks. Maybe I’m spoiled by metal, thread-on lens caps, but the Z10’s cap is made of hard plastic and snaps into the inside of the OTA. My old C8 was also hard plastic and attached in a similar way, but it was easy to get on and off. The Z10’s cap is difficult to get back on. I suppose that’s why I see so many people with shower caps on their dobs? Perhaps…
4) Not a bad thing, but consider the size and weight of this thing before you buy one. The Z10 is bigger than it looks. It’s slightly awkward to carry (in 2 pieces of course) although not uncomfortably heavy. I can easily carry it down a short flight of stairs and 25 feet into the backyard. It doesn’t make much of a living room piece either (according to my wife). She much preferred my 80mm refractor on an EzTouch over the “big, black, empty tube”. I was considering the Z12, and I am glad I stuck with the Z10 for its size. Anything bigger or heavier is approaching the limit of what I consider reasonable to carry and set up by myself.
I am quite pleased with the Z10. The included goodies and great price-to-performance ratio make it an outstanding value. It’s well made, works well out of the box, and the views are outstanding.
While it’s not perfect, it’s quite good for the money for any level observer.
Thanks for reading and clear skies.