Zhumell Dobsonian 10 in Telescope

This is a 10" (254 mm) Dobsonian mounted reflector from Zhumell - a company in Minnesota that used to be known for binoculars - but I think that these scopes will change that.

It has a 1250 mm focal length, and a ratio of F/4.92. The reported limiting magnitude is 14.52 and the reported maximum theoretical magnification is 600X. The resolving power is reported to be 0.46. The mirror is pyrex and aluminum oxide / silver oxide coated and center marked. With no extras you should get 139X out of the 9 mm. I bought a 3X barlow as well that takes it up to 417X and it handles that very easily. Nice and clear with good contrast. I'll likely order a 6mm eyepice soon to push the limit.

It came with a nice bright 8X50 finder scope, a fan (which takes 8 AA batteries), a great 2" dia. 32mm wide field lens and a 1.25" 9mm Plossl. It also came with a really useful laser collimeter and a moon filter for the short lens.

It is a large and heavy scope. It will fit in the back seat of your car but you won't want to move it much. Although you can carry it, it isn't the kind of thing that you want to move around the yard 20 times in a night.

I got this scope in 3 days with free shipping from binoculars.com - love that. It went together quickly (45 min.) and easily, and everything was there - great. It took less than a minute to collimate it with the included laser collimeter- awesome.

I looked at a lot of scopes before buying this one and it is really the best value for the money out there.

Unfortunately it has been quite cloudy since I got it so I can't comment much on the views except to say that in a small window I ran outside and saw an amazing number of crisp, clear stars for an hour. It is definitely able to pull in a lot of light and the limiting magnitude reported is likely on the money.

The focuser is beautiful, very stable and easy to use (both fine and coarse with locks on 2" and 1.25" lenses.

Dobs are what they are, but in that class, this base is as stable and easy to use as I've seen. It is easy to point and generally stays put.

One minor point, I had read about the (lack of) directions and printed them from the Zhumell web site before it arrived. I don't know why they don't just include them with the scope but they should. It was painless though.

Overall, this is a great value.

Note: I write reviews because I believe in the power of the internet to inform people and make life better. I don't read comments and I don't make them - or give ratings. Any meager earnings from my reviews go to charity. Thanks for reading my review

Update: After a couple of weeks of waiting - finally a clear night, a bit more info. The views of the moon are stunning, especially with a 3X barlow. The big lens is just awesome for general constellation and cluster viewing. Jupiter is confirmed present in the solar system and with significant color variation in the surface. It has been too close to the moon lately so I still haven't seen the dot but it looks like I could. It is also clear enough that I'm hoping to see ones of its moons cross it but I haven't been that lucky yet.

The only issue with mount has been that the bolts attaching the pivot ears to the tube all came loose last night. They have lock washers and were easy to retighten so they must have just not been as tight as they could have been from the factory. Not a problem, just something to watch out for.

Another Update: I've had this scope out for 2 seasons now and I'm still very happy with it. It still has a little issue with bolts coming loose now and then - I should probably just use threadlock. Some minor modifications have really enhanced the useability. I got a basic red, yellow, green, skyglow filter pack for it, the skyglow light pollution filter is useful, the other colored ones have not been of much use. I bought a $4 magnetic angle finder (for welding etc.) at Harbor Freight, it sticks on the side of the tube and gives a good reading on altitude (really cheap and simple). I also got tired of the inherent ambiguity in the altitude mechanism of the Dobsonian mount so I got an old crank type hand drill, adjusted all play out of it, mounted it with the crank gear bolted with its back to the left axle (ear) of the scope's pivot mechanism and the neck and handle attached to the base. I now have a very precise turning knob altitude adjustment (the knob is simply clamped in the chuck of the old drill) that makes it much easier to track and much more stable.

UPDATE:

We moved recently and a mirror mount bolt apparently vibrated out and was lost in transit. I emailed Hayneedle who is the retailer for these scopes and they don't sell parts but were kind enough to mail me two from a returned scope free of charge. Now that's customer service!