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PlugROCKSTAR
08-04-2005, 04:24 PM
Title Says it all. What do i look for?

thanks in advance
916

ghostfish_slayer
08-04-2005, 05:26 PM
hot chicks on the beach..

PlugROCKSTAR
08-04-2005, 06:20 PM
hot chicks on the beach..

besides that you smart arse :P

Oxbow
08-04-2005, 06:31 PM
Power is cheap, don't be impressed by it. Definition is expensive i.e. clarity or lack of "fuzziness" is what you want to look for. Make sure you take the unit outside for a look see. If you have good definition, you have a good lens. Compare an inexpensive unit to an expensive one and you should easily be able to tell the difference.
Good luck!

PlugROCKSTAR
08-04-2005, 09:39 PM
i was leaning more towards one with a Leica Lens. thanks for your input Oxbox.

Oxbow
08-05-2005, 07:59 AM
Leica is an old standard noted for fine camera and other lenses but the Japanese lensmakers passed them up quite a few years back with some of the best grinding and lens coatings in the business. Your best bet is still to take the unit(s) outside and compare for yourself. It's not the manufacturer but the definition that you want to look for. I would never buy binoculars by mail order, looking through that lens is the best way to compare. Hope you find what you are looking for!

FreshwaterFrank
08-05-2005, 02:08 PM
This is a subject I know a bit about, I'm an amateur optician & astronomer & have owned dozens of bino's over the years. With all optics, the intended use is critical. Like boats, there are different standards for different uses. If you need good low-light performance, you're going to have to have larger main optics...the second # in the description...as in 7X50. The "50" refers to the diameter of the main optic (lens) in millimeters. 50 mm. is 2". This is the standard for low light conditions. The first # indicates the magnification. For practical handheld use, 7-10 power is the max. Anything more is impossible to hold steady.

There are bunches of cheap bino's out there these days, it's tough to find a really good unit. Certain brands are known for quality, however...but as per usual you gotta pay for that quality. "Bargain" bino's are invariably pieces of crap...take my word for it. High quality optics are expensive. Names you can rely on, following my disclaimer (*) are.....Nikon, Canon, Bausch & Lomb, Zeiss, Leica, Orion, Svarkowski. The disclaimer follows....

(*) As Oxbow says, never buy bino's W/O trying them out first. Here's the reason. Bino's are basically two small telescopes, pointed at an object...one for each eye. Both small telescopes must absolutely point at the exact same spot...or the view will be distorted. This distortion can vary from just irritating, to headache causing. The alignment of the two optical paths is called "collimation", and the difference between quality bino's & bargain models, is the degree of accuracy & permanence of the collimation, and the perfection of the design & manufacture so that they will stay in collimation. Attaining perfect collimation, and maintaining it with use, is an expensive thing to do....there is no way around it. You can find cheap bino's that are well collimated when new...but they won't stay that way for long, because they're cheaply made & just normal use will over time "un-collimate" them. You get what you pay for, as usual. The brands I listed are known for high quality manufacture.

The best way to buy a good pair of bino's is to simply test them with your own eyes, and buy a pair you like...made by a quality manufacturer...that are well collimated. This is easy to do. If possible, use a tripod...but if unavailable, rest the binos on a flat surface and look at a distant object with both eyes. You should have no trouble getting a sharp, clearly defined image...in good focus. Place a distinct object or point in the center of the field of view (FOV). Then alternately open & close one eye, then the other. The chosen object should stay in the exact center through both eyes. Any shift, or difference, is the result of improper collimation. Only buy a pair of binoculars which exhibit perfect collimation! No exceptions.... Simple. There is no short-cut, poorly collimated bino's will never get better, and having them re-collimated is only worthwhile if you're dealing with top-of-the-line models...or vintage collectibles. In any case it's very expensive, and you cannot "do-it-yourself".

If money is no object, I recommend the Canon Image-stabilised bino's...they are unbelievable! You can stand on a pitching deck, and look at a boat a mile away & the image will be as steady as a tripod mounted bino on land...no kidding. At the moment, I am using a classic pair of Bausch & Lomb, 7X50 aluminum frame military model M7's...Korean War vintage. These are just a sweet pair I scored for peanuts, very lightweight. On the boat I use my trusty 7X21 Nikons...30 years old & still perfect collimation. They fit in my pocket.

A good place to look at binos & see what's out there commercially, is @ Orion. Check them out @ telescope.com

Orion has retail outlets in N.Ca. so you can check out any potential purchase B4 you put your money down. They're a good outfit, I highly recommend them.

SideJump
08-05-2005, 08:44 PM
FreshwaterFrank,
Wow... very informative. Makes me want to go out and look at binoculars now. This board is great because you learn something new everyday.
SJ

ghostfish_slayer
08-05-2005, 09:26 PM
yep, thanks for the info because i was thinking of buying a new pair also.sorry 916 i just had to throw that in there.. ;D

FreshwaterFrank
08-06-2005, 09:25 AM
Because I'm bored & someone may find some further info usefull.

A thing it's important to know prior to looking for binoculars, is what they will be primarily used for. The main distinction is going to be the low light conditions performance. "Night glasses" are defined as units which have an "exit pupil" of ~7. This fancy term is easily explained for the laymen. The exit pupil is the actual size of the image coming out of the eyepieces...in millimeters. The average human pupil (the black part of your eyeball), dark adapted at night, is 7 mm. diameter. Thus, an exit pupil of that size will provide the optimum view possible in low light conditions. All one needs to do in order to figure out what the exit pupil is, for any binocular...is divide the power into the diameter of the main optic. 7X50's are traditionally the standard night glasses...7 divided into 50 equals ~7. For practical purposes, any exit pupil over 5 will provide decent low-light performance, but more than 7 is a waste because your eye cannot take advantage of it. The drawback to 7X50's or larger bino's is weight & size. The larger/heavier the bino's get, the more difficult to hold them steady. I would strongly advise against any bino's over 7-8 power, or 50mm. lenses for hand-held use.

For daytime use, an exit pupil need be no more than 3, thus 7X21's are entirely adequate & can be superior in use, because they're so small/light & easily held. At night however, they are virtually useless. 6X35's are a good compromise.

The new image stabilised bino's are different, because they can be held so steadily on target by their electronic stabilisation. 15X40 is perfectly usable, and because they're so steady they even work well at night, despite their lower exit pupil. These new-fangled bino's are fantastic, if you can afford them...I wish I could. I have used them however, and can testify that they're a quantum leap beyond regular bino's....so long as the batteries are charged!

Other things to look for...

Coatings: Lenses should be "fully multi-coated" for optimum performance. This means that every surface of every lens has been given a coating of magnesium flouride, or another anti-reflection agent. You can see the coatings, as a coloration on the lenses. The best bino's will be "fully multi-coated", and will so state right on them. If they just say "multi-coated" or "coated lenses" then only the outside surfaces have been coated, so beware of the tricky terminolgy.

Prisms: prisms are the heart of any binocular. They're what turns the view through the eyepieces rightside up, and seperates the light paths to the proper inter-ocular seperation for a pair of human eyeballs. Bak-7 prisms are considered the best. Bak-4's are fine for daytime use, inferior for night-glasses. "Roof prisms" allow smaller, lighter & more compact design, and are favored by bird-watchers etc. but inferior for low-light use. They're also more expensive.

Mickey_Thomas
08-08-2005, 05:15 PM
Most binoculars are not build waterproof, if you take them on your boat put them in a sealed bag, or do what I do, I buy the 29.00 ones so if I dunk them I don't feel like I lost my best friend. Portable phones are the same, get them wet and they're toast. ??? 916 you never told us what you're going to use them for, FreshwaterFrank know's his stuff, good info there FF ;)

FreshwaterFrank
08-08-2005, 10:33 PM
Good point there Mickey. I'd go even farther and say that no binoculars are really totally waterproof. Especially for saltwater use. I never use my really good bino's on the boat. My Nikons have lasted so long because they are so compact I can just slip them in a pocket. German WWII U-Boat bino's are virtually waterproof, but they go for $1000+ these days. Oh well.....

HOOF
08-11-2005, 05:53 PM
Leopold,Ziess