Features May 15, 1998 Issue

ITT Night Vision 260—A Star Among Night Vision Scopes

When the only thing that keeps you from going aground at night is an unlit channel marker buoy, a night-vision device suddenly becomes less of a luxury and more of a necessity. They’re not cheap, but since their introduction to the civilian market a few years ago, quality has been going up, and prices have been going down.

We last reported on night vision devices in the March 15, 1995 issue. Since then, several new scopes have been introduced; some of the models we had discussed are gone from the scene, and one has found a new home and a price that’s about double what it was in 1994. We felt it was time for a fresh look at what’s out there.

A Little Background
Night-vision scopes originated with the military, which is hardly surprising. The earliest models—”Snooperscopes” and “Sniperscopes”— were developed during World War II. They were relatively crude devices that consisted of a spotlight that “illuminated” the scene with a beam of infrared light that was invisible to the unaided human eye and a sensor that converted reflected infrared to visible images. They were heavy, had poor images, and a very limited range. Their vacuum-tube technology required a lot of power at a high voltage, so that vibrator power supplies and bulky transformers were needed to boost the voltage of the heavy lead-acid storage batteries available at that time.

By the time of the Vietnam war, transistors and improved tube technology made it possible to amplify the low levels of available light without the use of a separate infrared source. The early “Starlight Scopes,” like their predecessors, were very expensive, with a great deal of this cost incurred during initial development. As time passed, much of the technology that made them work was declassified, and prices dropped enough to make the devices available, first to law-enforcement agencies and other groups, and most recently to the public at large.

While this was happening, the Soviet Union was disintegrating, leaving former suppliers of optics to the Soviet military turning to Western civilian markets for customers. The result has been a fairly dramatic reduction of prices, particularly for lower-end models.

The Generation Gap
Development of night-vision devices has occurred in discrete steps, referred to by the industry as “Generations.” The earliest models, which depended on an infrared spotlight as the primary light source (some newer models have auxiliary illuminators to help when it’s really dark), are referred to as Generation Zero. Limited range and low sensitivity make this equipment almost useless for marine use, and none is reviewed here.

Today’s equipment, whether it be Generation I, II, or III, functions by amplifying existing light; it responds to both visible light and a portion of the spectrum that’s not normally visible, such as the infrared and ultraviolet ranges. The basic component of all these systems is an image-intensifier tube, with a photocathode at one end and a phosphor-coated screen (like a TV screen) at the other.

In a Generation I device, a photon—the smallest unit of light energy—strikes the photocathode, causing it to emit an electron. The electron strikes the phosphor-coated screen, which glows at the point of impact. Two factors make this system produce an image that’s brighter than the original scene that’s being viewed. The phosphor produces several photons for every electron that strikes it, and the original photon that started the process may have been in a wavelength that’s normally invisible. There’s an objective lens at the front of the device that gathers light and focuses it on the image-intensifier’s photocathode; an objective, or eyepiece, lens focuses on the face of the phosphor screen for viewing.

There’s an inherent limitation in Generation I devices: The multiple photons emitted from the phosphor screen scatter, producing a fuzzy image. Greater light amplification means more photons; more photons cause poorer image quality.

Generation II devices addressed this problem by adding an additional stage of amplification between the photocathode and the phosphor screen. This stage consists of a “microchannel plate,” a bundle of very fine open tubes (the ITT Night Mariner microchannel plate has over six million of them) that are oriented so that an electron emitted from the photocathode can’t pass through without striking a tube wall, which is electrically charged. Electronics passing through pick up others, while the tube architecture keeps them from scattering, so that the electrons leaving any one tube all strike the same portion of the phosphor screen. Result? A bright, sharp image.

Generation III units became available for non-military use in late 1994. They function the same as G-II units, but use a different material for their photocathode—gallium arsenide—which makes them capable of greater light amplification. Which means you can see where you’re going in even dimmer light.

In the past, there have been a number of conflicting claims concerning which scope belongs to which generation, particularly among discounters peddling Russian imports. The fact is that most of the imports were Generation I models, and the few that used Generation II technology employed a cruder and less effective form of it than did the US-made devices. There are no Generation III imports —in fact, while it’s legal to take a personal unit out of the country, it’s illegal to sell one overseas.

What We Tested
We went through boating equipment, fishing equipment and hunting and outdoor equipment catalogs in search of night-vision scopes that would be suitable for a marine environment, and came up with a total of 10 models, seven of which we had looked at before. The field was dominated by ITT with seven models. Tasco, a new entry in the field, was represented by one model. The venerable Russian-made Night Hawk MPN 40K is still around, and the Intevac Night Mate Nav-3 is still with us, though it’s now manufactured by Litton Electronics, sold by a distributor called Night Line, and lists for twice what it did in 1994.

How We Tested Them
While some units make claims for gain (light amplification), we’ve found in previous tests that the best way to evaluate a night-vision scope is to go out on a dark night and try seeing things. This we did, supplementing our field tests with viewing a regular rectangular grating that acts as a security door on an underground parking garage—we’ve found that this makes an ideal grid for evaluating brightness and distortion of the image produced by the various scopes. We found that we could make independent judgments on brightness and image clarity (freedom from distortion). We also checked out items like battery life, lens interchangeability, water-resistance, and whether or not the unit floats—a consideration when hand-ling expensive equipment in the dark under less-than-ideal sea conditions.

What We Found
To nobody’s surprise, the Generation III models clearly outperformed the Generation II and Generation I models in terms of brightness. They also cost more. ITT, which dominates the field, makes most of its models with either Generation II or Generation III tubes. Across the line, the Generation II units list for $500-$600 less than the Generation III counterparts.

ITT Night Mariner 260
This G-III unit is a single-objective binocular—it’s a monocular that splits the light path so you can view things using both eyes. It’s a flexible unit, with a manual brightness control (supplementing an automatic gain control), independent focusing for both eyepieces and the objective and adjustment for interpupillary distance.

Controls are nicely grouped on the scope’s upper surface, permitting easy one-hand operation. Push-buttons that control the electrically actuated adjustments are large enough to let you operate the scope while wearing gloves. There’s a right side handstrap to help keep it from wandering away when in use. The Night Mariner 260’s bright yellow and black case is easily visible, is waterproof, and it floats. It’s powered by a 6-volt lithium camera battery with a claimed operating life of 13 hours; batteries should be commonly available. There’s a low-battery indicator and an automatic shut-off if the unit is operated in light bright enough to damage the unit. For not-too-dark conditions, you can operate the 260 with the objective cap on; there’s a pinhole in the cap that admits enough light for effective operation without any risk of damage.

It’s very difficult to fault any aspect of the Night Mariner 260’s performance. It produced a very bright, low-distortion image even on starless, moonless nights, allowing our testers to pick out lighted buoys several miles away, and unlit ones at distances of several hundred yards. There’s no magnification, although an auxiliary lens kit is available. Unless you’re planning to go in for infrared night photography, we don’t think that it’s necessary. Also available is a focusing-beam infrared illuminator, for relatively close-up work in extreme darkness.

Bottom Line: The ITT Night Mariner 260 is excellent in terms of brightness, image quality, and convenience. On the basis of performance alone, it’s our clear winner. Downside? Well, at more than 28 ounces, the 260 is one of the heavier models tested. And, at a list price of $2,495, it’s one of the most expensive. And we wish that ITT would captivate the lens caps because they’re just too easy to lose.

ITT Night Mariner 250
If it weren’t for a small logo on the Night Mariner 260 that reads G3, the Night Mariner 250, from the outside at least, would be indistinguishable from the 260. Inside, as far as we can tell, the only difference is that the 250 uses a Generation II tube. Everything we said about the 260 applies to the 250, with the exception of brightness, which we judged to be very good rather than excellent, and price, which is $1,995.

Bottom Line: The 250 has sufficient light amplification to get you safely home in any but the very darkest of nights.

ITT Night Mariner 160
The 160 is a straight monocular, stripped-down version of the 260. It has the same G-III tube, so that brightness and image quality are both excellent. Our testers found that one-eye operation wasn’t as comfortable as the two-eye operation possible with the 260, but there may be an advantage in using a scope that will only spoil the night vision capability of one eye. Focusing is purely manual, instead of the electrical system on the 260. There’s an automatic brightness control, but no supplementary manual one; interpupillary distance adjustments is, of course, unnecessary when you’re viewing with one eye.

Again, there’s no magnification unless you purchase an auxiliary lens. Unlike the 260, the 160 runs on two AAA batteries, which provide 30 hours of operation. The unit is considerably lighter at 16 ounces and less expensive at $1,595 than the binocular version. The case is also yellow and black. It’s waterproof and it floats. And the lens caps (including the one with the pinhole for brighter-light operation, are captivated. The same lens kit and illuminator sold for the 260 and 250 models fit the 160 (and 150).

Bottom Line: Rated excellent in brightness, image quality, and convenience, the 160 isn’t quite as comfortable for viewing or quite as adjustable as the binocular/monocular 260, but it’s a lot less expensive and a good deal lighter. The image is just as good.

ITT Night Mariner 150
The Night Mariner 150 is a Generation II version of the 160. The image isn’t as bright, but the units are otherwise identical.

Bottom Line: At a list price of $995, the Night Mariner 150 has a definite appeal, particularly if the background light levels in your area keep your viewing scene from utter darkness. We rated it excellent in image quality and convenience and very good in terms of brightness. We think it’s a good choice if you don’t insist on the very best.

ITT Night Mariner 210
The 210 is one of ITT’s newest models. Like the 260, it’s a single-objective binocular, but it’s smaller and much lighter than the 260 at 15 ounces. The 210 is a Generation III unit, so the brightness is excellent. We found that the lenses used aren’t up to the high standards set by the 260, 250, 160 and 150 models. Image quality was rated as very good. We’re told that optical performance will improve with the optional lens kit, but we’re not convinced. Adjustments on the 210 are manual, not electrical. The Night Mariner 210 is supplied with a headband holder that permits no-hand operation once the unit is focused. It’s also equipped with a “C” lens mount that will accept a wide variety of lenses. If you use the existing lens, there are rubber lens boots that will keep the unit waterproof; if you opt for a change of lens, it’s not. The Night Mariner 210 is waterproof and floats (if you use the lens supplied). It uses the same camera-type DL223A battery that the 260 and 250 do.

Bottom Line: The major advantages of the 210 over the 260 are lighter weight, changeable lenses, and its capability to be used with a headband. If these factors aren’t of vital importance to you, we think you’d be happier with the 260’s better image at a very slightly higher price. The ITT Night Mariner 200 is the Generation II counterpart of the 210. Not quite as bright, $1,895 instead of $2,395, and otherwise identical.

Tasco NV245
Tasco is a newcomer to the night-vision scene and, after studying their NV245, we’re not sure why they bothered. It’s a Generation II device made in Russia and is very similar to the old Russian Baigish B-6 we reviewed several years ago, except for a Pentax screw mount for lenses. Neither image quality (fair-good) nor brightness (fair) come near matching the less expensive ITT scopes.

It was the least convenient scope we tested—at 57 ounces, it’s heavy as well as poorly balanced, and the controls are awkwardly located. The screw-mount lens precludes it from being waterproof and it carries a lofty suggested list price of $3,039 (although we’ve seen them discounted to $1,350 or less).

Bottom Line: Why bother?

Night Hawk MPN 40K
The Night Hawk dates back to 1961. It’s a Generation I unit that’s a true binocular with two eyepieces and two objective lenses. Its major claim to fame at this point is its low price—$460, down from $750 a few years ago.

Brightness is about what you’d expect from a Generation I unit—better than no night vision, but not as good as other scopes tested. We rated its image quality only fair, due to a generally fuzzy image with distortion that increased towards the image’s edges. Although the Night Hawk is heavier than any of the US-made units, we found the handling good.

Bottom Line: The Night Hawk is a good example of obsolete technology. Its low price is tempting and its performance is just good enough to be a help if your harbor isn’t too dark. On the other hand, it’s nowhere near as good a scope as, say, the ITT Night Mariner 150 monocular, which lists for $535 more.

Night Mate Nav-3
We tested the Generation III monocular Night Mate Nav-3 in March 1, 1995 and concluded that, although its optical and electronic performance was excellent, and its light weight and small size were tempting, the fact that it wasn’t waterproof made it a poorer choice for marine use than the ITT Generation II scopes (ITT hadn’t introduced their G-III models at that time). After some years of consideration, during which time the Nav-3 moved over to Litton Industries, and is now marketed by Night Line, our opinion hasn’t changed. It’s a fine scope, but not, we think, for use on small boats.

Technically, the Night Mate has some interesting features. Night vision scopes normally produce an inverted image, and rely upon an arrangement of lenses or prisms to produce an upright image. The Nav-3 uses a “twisted” microchannel plate to erect the image, saving both bulk and weight over the more usual arrangement. There’s a built-in illuminator for close-up work in very dark conditions, and a “C” mount that will accept a wide variety of commercial video lenses. The price of the Nav-3 has jumped from $1,600 to $3,114 since 1994.

Bottom Line: The Night Mate Nav-3 is lightweight, versatile, convenient, and expensive. It’s also not waterproof. We don’t recommend it.

ITT Night Mariner 190
Considering the incestuous relationships that are common in the electronics industry, we suspect that there are more than a few common technological genes shared by the Night Mariner 190 and the Night Mate Nav-3. They look similar, utilize fiber-optic image-inversion technology, and work pretty much the same (although the Night Mariner 190 doesn’t come with a built-in illuminator). The 190 lists for $1995. Like the Nav-3, it uses “C” mount lenses. And also like the Nav-3, it’s not waterproof.

Bottom Line: The Night Mariner 190 is a fine scope, particularly if you’re interested in night photography. For marine conditions, however, we think that a waterproof night vision scope, such as ITT’s Night Mariner 160 at $1,595, is a safer choice.

Considering the number of night vision scopes ITT makes, it’s gratifying to say that we haven’t found a bad one in the bunch. Our top choice is the Generation III Night Mariner 260. The binocular viewing is extremely comfortable, the electrically actuated controls are extremely convenient, and the performance is excellent. If $2,495 is more than you’d care to spend, the monocular G-II Night Mariner 150 lists for $995, is handy, and will do fine under all but the darkest nights.

The Night Hawk is tempting, solely because of a $460 list price; if we couldn’t afford a Night Mariner 150, and we really needed a night vision aid, we might be tempted. Probably, though, we’d be better off saving our pennies for something better.

Contacts- Night Hawk, Moonlight Products, 5965 Pacific Center Blvd., San Diego, CA 92121; 619/625-0300. Night Mariner, ITT Electro Optical Products, 7635 Plantation Rd., Roanoake, VA 24091; 800/448-8678. Night Mate, Night Line, Box 16-089, Miami, FL 3316; 800/319-4977. Tasco, Tasco Sales, 2889 Commerce Pkwy., Miramar, FL 33025; 800/368-2726.

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