Zhumell 25x100 Tachyon Astronomy Binoculars for Deep-Sky Observing

OK so not easy to grab and run out and view. I doubt seriously if anyone is steady enough to hold these still in their hands for astronomy type viewing. I have em on an Orion Telescopes Monster parallelogram and they work pretty well. Still I get better views when I get on target and take my hands away. No vibration at all that way. The moon is awesome. Looking tonight with maybe a quarter moon we could easily see crater and mountain details and easily see the mares in the shadow. M42 is realy nice. I haven't seen this much with aging eyes in a while. 4 moons of Jupiter were really clear. My minds eye thought I could see some color on the disk but I was never super clear about that. Pleiades were absolutely fantastic. They take up almost exactly the whole field of view through these and are amazing to look at. You get a depth of field through these that you would never get with one eye on a telescope. Everythings is nice and bluish. I've got or had 2.1x41s, 2x54s, 10x502, 8x60 & 20x80s binocs. Telescopes that range from the silly 35mm up to 13". I make a lot of my own stuff and I'm working on a set of DIY 100mm f4.5 binoculars that I started right before my wife bought me these. I may never finish those because these are so good I can't imagine coming close. Cons: 1) They are expensive but not so much compared to other similar astro binocs. I doubt I would have bought em myself cause I would never have thought they were so much better than my 20x80s. They are. 2) They are heavy. You won't freehand em and do well so plan on building or investing in a BIG mount. 3) My wife thought she was getting me a birthday present but they were basically useless until we got the mount. It was $500 and she bought me that for our 31st anniversary. I was planning to build one but her's is better. Just expensive. 4) The mount and binoculars are almost too heavy to run out and look at something quick. I have a bad back and I often want to go out to view but I can't justify the pain caused by totin' that mount so I have to wait for one of my boys to take em out. I want to make a permanent safe place for them on my patio so I can just go out and view. Problems to overcome... If you are the kind of person that only wants the best then these may not be for you. If you want some very good binoculars for the night sky then I think you will be happy with these. If it weren't for the costly and necessary mount I would recommend these for a first scope. You will definitely see more than I ever did with my first 5 scopes.

The Binocular is well built and robust. It was in good collimation. The views through the large 100mm Aperture is amazing. I also own 50mm and a 35mm binoculars, so the difference in viewing is very noticeable. Be aware that you cannot hold this in your hand. Need a heavy duty tripod capable of holding 15lbs to be reasonably stable. Also look for a tripod that can reach at least 72” height for comfortably viewing stars. I purchased a Neweer 77” heavy duty tripod to mount this binocular. I replaced the Tripod’s standard 1/4”-20 0.25” screw with one that was 1.5” long, as the standard short screw has only 3 or 4 threads, so insufficient to attach this heavy binocular. The mounting post on the Binocular is threaded to accommodate a long mount screw so use it to its full depth. Overall very pleased with this Binocular. It is now permanently in my car with the tripod, so that i can grab any star gazing opportunity i get when i am travelling.

The collimation went out all of sudden, and you see double of everything, and that ain’t a good thing! It was not dropped or shaken to my knowledge. There’s no way to fix it and the company offers no such service. User manual is pretty useless beyond basic kindergarten-level information.

The rumor is that Zhumell is made by Celestron, which could be a very good or very bad thing because Celestron has run the gamut of making incredibly good and bad stuff (their cheaper stuff is not so great unless it's your first pair of binos). Well this shipped from Torrence CA and that happens to be where Celestron is, so I'd bet the rumor is true. However the optics and construction are excellent, I was very pleasantly surprised. This is a nice professional grade set of binoculars, they are ridiculously heavy and it's not fair that people reviewed them poorly based on this, because that is the nature of the beast. If you want giant binoculars, they are going to be heavy. Don't buy a big truck for offroading and then complain it won't fit in your garage lol. If you are attempting to use these without an astronomy tripod you will be disappointed. Even many camera tripods can't handle this weight and you'll stress the head and joints and permanently loosen up your tripod. Get an astronomy one, Orion makes a nice affordable one and perhaps some heavy duty camcorder tripods can handle the payload. I found stars to be crisp and sharp, with some edge distortion expected on the further outreaches of the view which is acceptable in binos of this size and price. Focusing was precise with the oculars a bit hard-turning. Eye-relief for glasses wearers is also ok, it's usable but not the huge eye-relief you'll get in some lower powered binos. The big NEGATIVE for me was how Zhumell designed the eyepiece as an eyeglass wearer. They made it metal (which I believe can accept threaded color filters like a telescope) and with a serrated outcropping which knocks against your glasses, and this is why I ended up returning these. You WILL scratch your glasses eventually using these over time, so you probably will need a separate pair for stargazing. I think this was something easily remedied by the Zhumell design team and I'm really kinda shocked they didn't address this issue. Metal contacting your glasses isn't a good thing, especially since all other bino manufacturers use a rubber eyeguard. That's really my only complaint. These are good quality sky-eating binoculars. If you are wondering if you should go this big or get something a little smaller, I would say it depends on your sky condition, and if you live in a dark sky area. These binos WILL reveal more stars and deeper objects, but only marginally over a good pair of 15x70s or 80s, and I do mean a good pair (not a $100 pair). You are not going to see a ton of Messier objects or gigantic planet views as it's only slightly better than a smaller pair of binoculars. But it is better, and brighter. Andromeda is more noticible, and you see more stars in star clusters and constelations than you'll see in a smaller pair. These will reveal more, period. In dark skies, even more so. You'll see Jupiter and it's moons a little better, and you can barely make out Saturn's rings (it's still a small object in the view) but it's not anywhere like a good telescope. However the stereo vision of a binocular is in my opinion better than most telescopes, even most expensive telescopes. What I am saying if you think these binos are going to open up the heavens so you can see M-51 and other deep sky objects, it's only slightly better than smaller binos and most of these objects still appear as smudges or dim marks in the viewfinder. Couple that with the hassle of needing not just a tripod but a big tripod, and I wouldn't take these out as often as I would a good pair of 15x70s or 80s. So that's up to you. These are spectacular binos if you can get past the eyeglasses issue and have a great tripod and you are aware of the viewing limitations. They are the quality of something $500-1000 and at this price are a steal.

The binoculars themselves are really quite amazing. They are much bigger than I had imagined. I knew that they were going to be big, but you really have to have them in front of you to appreciate the size and weight. You absolutely have to have a heavy duty tripod to properly use these bins. Be prepared to spend another $100 or more on that. These are definitely not for casual, handheld use. Great views. Great lenses. My only complaint would be the case that they come in. It looks good, but its looks are deceiving. Mine was completely broken on one side, like it had been dropped. Or sat on. Not a good first impression for sure. Thankfully, the bins were not damaged.

I am an amateur astronomer of 62 years experience. I own 10 " and 5" catadioptric telescopes. I purchased the25x100 tachyon binoculars to see wider fields and retain good light gathering ability. They arrived in excellent condition, and in very good collimation. The moon and venus were well imaged. Chromatic aberration is minimal for refracter optics of this size and fast focal ratio. I have used nebular filters in the eyepiece, as they are made to use them. The views of galactic nebulae, open and globular star clusters, and galaxies is very good. Larger nebulae, like the Orion nebula, M42, the lagoon, M8, and the veil nebula, NGC7009 are spectacular in this size binocular. The open clusters like the Pleiades and the double cluster in Perseus are at their finest in this size binocular. This also is an excellent optic for viewing comets. I use it with heavy duty tripod mounts as well as a good monopod. This binocular excels in the night sky. Can also image the major planets well given the magnification, which is minimal for planetary imaging.

Large amount of chromatic aberration in the blue. Have attached photo and very visible in upper right. Shot with iPhone 11 max, high res. Nice and sturdy unit and wanted to like but between lens shift and overall weight just not going to work out.

Seemed to be well made from a materials standpoint; however, the chromatic aberration was terrible - my expectations weren't unreasonably high given the price point, but at the end of the day the purple fringing around even planetary viewing was not acceptable. I viewed Jupiter, Saturn and Mars with these and even at those distances and this magnification there was a lot of fringing - I tried some high quality filters, but even they couldn't overcome the issue. View of Jupiter's moons was good as their magnitude was low enough that they did not fringe, and off-center viewing did allow me to discern light banding shadows on the planet. Stars were fairly sharp, so it wasn't a collimation issue, just seems like the lens quality is not where it needs to be. I really wanted to like and keep these, but at the end of the day I couldn't justify it.

La calidad del producto es muy buena, no he tenido problemas de colimación, o cualquier otra cosa tras dos años de haberlo comprado. el que incluya estuche rígido para guardarlo es un gran extra.