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Update!
After taking the binocs on a trip and having the alignment go out one time (from being knocked about a LOT), I DID find that it has alignment adjustment screws. 4 of them, just under the rubber cover on the prism assemblies (2 on the inside bottom near the focusing wheel, hard to locate). If you unscrew the main objective lenses and look inside the prism housing, you will see what look like very tiny pins pressing on the sides of the prisms, this will let you see where the alignment screws come out on the outside of the binoc housing. Otherwise, they are very difficult to find (very small) under the rubber sleeving. You will have to lift up a corner or 2 of the rubber to adjust the screws. I'm even happier with this purchase now that I found them. p.s. In real use for night-time and day, they worked great. I was especially impressed with how well they worked with the night-sky (I gave some short astro-lectures at some campsites for others with them). Even when used at 30x the image was rather crisp. In daytime at 30x they worked very well if supported on my knees or up against a tree. Who says you can't hand-hold binocs at 30x? It must be people with nerve disorders. :-) On Sun, 22 Jun 2003 13:21:21 GMT, HandyAndy wrote: Celestron 10-30x zoom 50mm objective UpClose-Series Binoculars Price: $49.99 from www.heartlandamerica.com (the cheapest price I could find). (An unconventional product review.) I will be heading out on a lengthy many-months backpack/kayaking trek and wanted to get a decent, all-around, every-purpose, knock-about, binoculars that I wouldn't mind losing if I fell down a cliff-side. I didn't want to spend much at all, but still wanted something usable with some decent power, zoom, and light-grasp. I ideally wanted to get some 8-24x zoom binocs with 60mm objectives but couldn't find any. Also, anything I looked into at 60mm objectives were ungainly huge in size, length, and weight. More than I cared to backpack for months. At 10x-50mm, when you work out the math, that's the same light-gathering power as 7x35 binocs. So I wasn't gaining anything by settling on 50mm objectives in this zoom range, but ... you do what you gotta do with what's available out there. I knew the drawbacks I was facing getting zoom binoculars, but thought, "What the hey, if I can get them cheap, let's see what they can do." I looked online at many models of zoom binocs (in the economy price ranges). The Barska 10-30x50 looked promising but they had that obnoxious ruby coating and I didn't know if there would be an easy way to remove that without destroying the lenses (and also an even narrower FOV). The Oberwerk 10-30x60mm from www.bigbinocs.com looked even more promising, fully broadband multi-coated, BAK4 prisms, etc, but the size was huge, and the FOV was an even narrower 3.5 degrees at 10x. I found another obscure-maker pair at the 8-24x60, JUST WHAT I WANTED, and they were even cheaper! (but can you imagine the construction and optics of those?) but alas, they had that damn ruby coating on them too which would negate any extra light grasp I could get from the 60mm's. Sigh... I received a thin catalog in the mail for the above company (Heartland America) one day, saw these Celestron ones with BAK7 prisms, fully-coated optics, a 4.1 degree FOV (at 10x), only $49.99, and ordered a pair. After all, they had the honored Celestron name on them! (Yeah, I know, Tasco owns them. :-) If you are not a handy-man with optics and mechanics, save your money!!! I would have sent these back, no questions asked -- IF I was not who I am. Quality of these are more on your Tasco-level of construction than Celestron. But more of the Celestron optics quality (after repair) than Tasco, an odd mix. However, after: 1. Resetting one of the objective lens housings that was screwed in crooked to the prism housing. 2. Digging out one of the objective lenses from its plastic housing. (No easy task going through glued plastic without doing some damage to the plastic. The other lens was not glued in and was easy to readjust.) 3. Recutting the lens housing plastic threads with a thread tap. 4. Adjusting the objective position in each lens housing so that the travel at one end of focus would stop at infinity. (They were set into the barrels too far and were hitting infinity at about 1/2 the focus adjustment range, cutting down my close-focus to about 80 ft. And originally each one was set for a different focus too.) 5. Using quite a bit of strength to remove the last vestiges of miscollimation in a vertical axis by bending the whole pair of binocs in one direction every so slightly to get rid of the slight offset at the 30x zoom setting. (There are no collimation adjustments other than if you shim the front lens assemblies with foil or something, I had not had to do that yet. The permanently affixed prism assembly itself seems to be very well adjusted as-is. Any initial miscollimation disappeared if the lens housings were screwed into the prism housing as tight as I could go. I only had that slight miscollimation at full 30x show up and used the brute-force method to remove it. One view higher than the other just enough to be noticeable and annoying. Laterally they were perfect. Exact collimation at 30x for 2 optics assemblies is quite a feat, you have to admit.) After all of that horsing around I got some pretty decent optics out of this inexpensive puppy. If only they were assembled properly in the first place. All that rotten quality control was hiding some decent lenses and optical performance. After the objective lenses were readjusted for proper infinity focus then I could get a close focus of about 25 ft. The zoom eye-pieces, while having a rather short eye-relief (and you need precise eye placement at 30x), are usable and the rubber eye-cups fold down to give you a little more working room. Their zoom mechanism also seems to be very well synchronized (tied to each other internally by a strong spring-steel metal band), with no (to nearly no) readjustment of focus throughout the whole zoom range. I've not used them at night, but daytime views afford a very bright and crisp image at the 10x setting with no chromatic aberrations at all. When viewing clouds within 15 degrees of the noon sun I notice no lens-flare at all. The image dims rather rapidly as you zoom-in (normal and understandable) and the FOV widens to keep pace with the zoom setting (you're just enlarging the original FOV view), up to a point (at about 18x) where it vignettes on the sides within the optics internal eye-piece and housing limits, if your eyes aren't close enough. If you fold down the rubber eye-cups then the FOV widens during the whole travel up to 30x. The view is crisp and clean all the way up to about 20-22x power, then it tends to get a little soft. But I've noticed new details in the 30x view (when steady on a tripod) that could not be seen in lower magnifications, showing that it's not just empty magnification. It's useable, but a tad softer. At powers of 22-30x I also notice some violet flaring around bright high-contrast objects in daytime views. As previously mentioned I've not used the binocs at night yet so I can't tell you what kind of star images it will provide (going by daytime views I surmise the lower power views will be more than usable, the narrower than usual field of view in all zoom binocs providing a challenge for night-time use anyway). Focusing is tight, both physically and adjustment-wise. Just a little movement is critical on higher-power views. It also doesn't take much movement to adjust it for it's whole focus range, the focus adjustment only has to turn about 90 degrees of a full turn from closest to infinity. There was originally some slop in the focusing adjustment. I tried to dismantle the focusing mechanism to see if I could insert a washer or shim to tighten that up, but couldn't get into it easily even after taking apart all the screws and things that I could. So instead I took some 20lb-test nylon monofilament fishing-line, and wrapped a few turns of it down inside around the axle between the focusing knob and the binoc hinge/housing, tied off a suture-knot, and trimmed the ends out of sight. It was just enough to act as a thin nylon washer to remove all play. Works *really* nice now with no backlash nor slop. It comes with 4 soft plastic lens caps (that I put small slots into, and strung black nylon shoe-lace through so they are attached on tethers to the binoc body (through the neck strap mountings) so I don't lose them while hiking). A soft nylon, square, binocular case (flimsy, slightly padded, but usable) with velcro closure. A soft nylon neck strap. And a micro-fiber lens cleaning cloth. A tripod mounting for it is an additional accessory found online for about $18-$30 depending where you shop. It's a simple L hunk of metal attached to a 1/4-20 thread hole in the end of the binocular's hinge front, under a plastic cap. I'm not going to pay $20 for a little elbow of metal, so I bent one of my own, drilled two holes in it and used some 1/4-20 thread nuts & bolts. 15 minutes of piddling around and for less than $1 I have something just as good if not better than what they sell at over-inflated prices. If you do want to buy one you can find a cheaper in-house brand-name at www.adorama.com for (if I remember) about $15. I didn't want to bother, making my own was faster and cheaper. Hand-holding is doable up to about 18x if you're very steady (as I am), but anything beyond 14x would probably have to be on a tripod for the average person. 30x for me is okay if I'm leaning up against something, but the view is still jittery. (There's a nice scale printed on the left eye-piece that shows you what zoom setting you are at (marked as 10, 14, 18, 22, 26, & 30x). Zoom is adjusted by a well placed, wide, and easy to use thumb-lever on the right eye-piece. A "+" and "-" diopter adjustment is also on the right eye-piece.) Considering the the narrow 4.1 degree FOV (@10x) and you will have to learn to aim them well if trying to find a bird in flight on your first attempt before it's flown out of range. The binocular body itself is rather light for their size (a major plus for my backpacking needs), the main objective barrels being strong plastic coated in a thin but strong rubber sleeve (which I removed and put back during repair). The rest of the binocs are metal and are also coated in that rubber coating (or rubberized flat-dark-gray finish). They seem to be rather durable and solid. They feel and behave like much more than $50 worth (after my fix-ups), that's for sure. Conclusion: If you just love to rebuild things, tinker 'til your heart's content, save money in the process, and take pride when you can save that poor unloved and unkempt puppy from the dog-pound -- then by all means GET A PAIR! I love them as they are now. Very functional, nice, sharp, precisely collimated, views, etc. etc. If you're not like me and you expect top performance right out of the box -- save your money. Or take a chance and hope you get a pair that was assembled properly (though I bet your chances of that are slim to none). The front objectives are some pretty hefty looking achromats (about 1/2" thick at the edges) when I removed them during repairs. I was impressed. I definitely got more than $50 worth in optics parts out of this deal. And was even happier when I could make them work as their designer had intended. Why didn't I send this pair back and try another you ask? 1. They were out of stock after their first shipment. 2. I didn't want to hassle with shipping and waiting at all. 3. I love a good repair challenge. 4. I love saving something that others would throw away. 5. How else could I have told you in such detail on how they are built and what's inside and what's wrong and right with them? 6. I would have eventually taken them apart anyway to tweak them. To me, a "No Serviceable Parts Inside" label is like waving a red-cape in front of a bull. There's not one thing I own (even SLR cameras, VCR's, analytical lab balances, and microscopes) that I've not taken apart and made much better. All the while shaking my head and going "Tsk tsk, who designed/built this piece of crap, this needs to be like this and this should be like this....." and then I do it. A patent-hound would be in heaven if they ever found my home and took apart all my toys to see what's different inside. :-) |
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