Experience with cheap binoculars?

March 25, 2008 10:57 PM

cheap ass chinese binoculars - worth the peanuts?

If you look on ebay or a more upmarket dollar store you can find binoculars with massive magnification for a few dollars.
When I were a lad, I would very much have liked such a pair for viewing the night sky.
I have kids now, and they dig looking at the moon with my old 8x50 pair. A more powerful pair might be fun, but not if it is hundreds or thousands of dollars.
Are ones like this or this any good at all? Would they be up to resolving Saturn's rings, for example?
I'd especially like to hear from people that own them, rather than people who own and recommend expensive alternatives.

posted by bystander to Science & Nature (6 answers total)

Oh...and assuming I mount them on a tripod as that magnification would be very shaky.
posted by bystander at 11:09 PM on March 25, 2008

I bought a pair of Oberwerk 20x80 binoculars a couple of years ago for about $120. They seem fairly well made, better than I expected. They are fairly heavy, but I can hold them and look at the moon fairly well without the image shaking too much. I got them not for astronomy, but used them on ships, and even with the motion of the vessel the image is OK. I had problems with them at first before I figured out the collimation needed to be adjusted. These have a fairly good tripod mount, but they seem like they might be a little awkward to use for astronomy on a tripod (from the one time I used a tripod).

I have no experience with the binoculars you linked to, but I have used a lot of lower powered binoculars over the years and have seen cheap ones that worked well and mid to high priced ones that were not so great. I think a lot of it has to do with whether or not they are adjusted properly, if they can be adjusted at all.

Again, I have little experience with astronomy, but from what I understand telescopes in your price range should have much better magnification and "quality" than binoculars since they are simpler and don't require lining up what are basically two telescopes. You'd probably have better luck with a starter telescope set which seem to come with star guides as well.
posted by Yorrick at 12:20 AM on March 26, 2008

Thanks Yorrick. The kids (7yro, 5yro and greasy fingered 2yro) have played around with telescopes, but they are quite difficult to use for little hands as they have a much smaller field of view and the image is reversed, both aspects of which make them hard to target compared to binoculars, at least until they are a bit older.
posted by bystander at 3:44 AM on March 26, 2008

I'm far from an authority on binoculars, but I did write a telescope review once, so feel vaguely qualified to tell you what little I know.

1: Binoculars certainly can be useful for astronomical observations, and not just for the kids. Light-gathering is more important for a lot of amateur astronomy than magnification; thus, low-magnification binoculars (10X, or even less if you can get it) with large objective lenses (at least 50mm) can work quite well. Large cumbersome models come with a mount for a standard photographic tripod, a cheap 'n' cheerful version of which will not cost you much.

2: Binoculars can actually make it easier to see things than a telescope, because both of your eyes are getting a picture, rather than only one. Provided the binoculars aren't delivering wildly different images to each eye (see Yorrick on adjustment, above), your brain will find it easier to see things through both eyes than through only one, all other things being equal. This applies to normal terrestrial observations, too.

3: Cheap zoom binoculars are almost certain to be garbage. And for astronomy, the alleged 100X-or-whatever maximum magnification of zoom units would be useless even if it were optically great, which it definitely won't be.

4: Non-zoom binoculars that at least look like astronomical units can be had amazingly cheaply on eBay. I'm looking at 20x80 "Sakura"-branded units with a tripod mount going for 59 Australian dollars, delivered, on ebay.com.au right now. At that price, even if they turn out to be pretty much toys, what've you lost?

5: That said, some cheap eBay binoculars are, apparently, fraudulently advertised. You buy a suspiciously inexpensive "20x100" set, but what you get only actually has 70mm objective lenses. But it does have "20x100" printed on it, and the seller of course professes ignorance of such technical trivia. A significant percentage of buyers are apparently so dumb that they will not notice being ripped off like this.
posted by dansdata at 6:15 AM on March 26, 2008

I'd risk it for $20.
One drop and those binoculars are toast. Unless you'll be supervising and cautioning with a more expensive pair...
posted by alicesshoe at 12:47 PM on March 26, 2008

I got a pair of 20x80 from ebay branded Sakura that dansdata mentioned.
They are of pretty good quality for such a paltry price, and good value for my limited requirements. One down side is the lens is coated with orange anti-reflective stuff, which cuts down light gathering slightly, but is no big deal.
They appear to have an adjustment for collimation, although they are OK with the factory setting.
The body is pretty rigid, although appears to be a dense plastic, coated with a non-slip material. The frame is metal. I wouldn't want to drop them, but they seem sturdy enough.
posted by bystander at 10:39 PM on April 24, 2008