Night Vision Binoculars

Image intensifiers

Night Vision Binoculars for Marine & Boating uses. If you are looking for more navigation equipment and spend a good portion boating at night then a pair or set of Night Vision optics are worth looking at. The ability to see especially in crowded areas, navigational channel markers and other boats at night will greatly enhance safety.

Night vision Binoculars types

  • Thermal Imaging
  • Image intensifier

Thermal Imaging

Thermal Imagers detect heat sources, Warmer objects emit greater infra red energy than cooler objects. Due to thermal Imagers capturing heat sources they can work in complete

Thermal Imaging

darkness. Because of the cost of thermal imaging, most Night Vision devices use Image Intensifying. Night Vision optics come in a variety of types; Binoculars, monocular and special devices that look like and are military in nature.

Prices of night vision technology has come down due in part to the research in military fields which makes the older generation devices much cheaper and the competing eastern continents producing low cost knock offs. Many of the high tech products produced in the US cannot be sold overseas.

A lens captures the infrared energy or light emitted by all of the objects in its view. The captured light is scanned by a phased array of infrared-detector elements. The detector elements create a thermogram. The thermogram is created from several thousand points, in the field of view. The thermogram created by the detector elements is translated into electric impulses. The impulses are processed and the information translates into data for the display. The data appears as various shades depending on the intensity of the infrared emission.

Thermal Imagers are also known as infra red. This split image shows a daylight thermal image next to a normal image. You can see the thermal image is like a black and white negative.

Image intensifiers

Easy to spot by the green images

Image intensifiers
Image intensifiers

Most of todays image intensifiers work by taking the small amount of light produced by starlight, moonlight or ambient light from man-made sources and converting it from photons to electrons – visible light to electrical energy. Electrons then pass through a microchannel plate. These plates contain millions of channels that propagate even more electrons as the first electrons pass through. Finally, this avalanche of electrons strikes a phosphor screen that converts them back into photons visible to the human eye. Image intensifiers need some light and cannot work in complete darkness

 

Wiki types of night vision

Image Intensifiers, light amplifiers work by taking the ambient light which is made up of photons and passing it through a photocathode tube that changes the photons to electrons. The electrons are amplified via a chemical and electrical process. The amplified electrons are then passed through a phosphor screen, which changes than back into photons. The amplified image is seen in green, as its this color which the human eye can distinguish between various shades the best.

image and description courtesy of Morovision.com Prices of Night Vision Monoculars or Binoculars range from a few hundred dollars to $5,000 plus. So what do we get for the price difference. That is easily explained by the generation of the devices. The generations are shown below

Generation 0 – The earliest (1950’s) night vision products were based on image coversion, rather than intensification. They required a source of invisible infrared (IR) light mounted on or near the device to illuminate the target area.

Generation 1 – The “starlight scopes” of the 1960’s (Vietnam Era) have three image intensifier tubes connected in a series. These systems are larger and heavier than Gen 2 and Gen 3. The Gen 1 image is clear at the center but may be distorted around the edges. (Low-cost Gen 1 imports are often mislabeled as a higher generation.

Generation 2 – The microchannel plate (MCP) electron multiplier prompted Gen 2 development in the 1970s. The “gain” provided by the MCP eliminated the need for back-to-back tubes – thereby improving size and image quality. The MCP enabled development of hand held and helmet mounted goggles.

Generation 3 – Two major advancements characterized development of Gen 3 in the late 1970s and early 1980s: the gallium arsenide (GaAs) photocathode and the ion-barrier film on the MCP. The GaAs photocathode enabled detection of objects at greater distances under much darker conditions. The ion-barrier film increased the operational life of the tube from 2000 hours (Gen 2) to 10,000 (Gen 3), as demonstrated by actual testing and not extrapolation.

Generation 4 – See the Night Vision Equipment Expert Blog for a good explanation of this commonly misunderstood advancement in night vision technology. See also: Gen 3 PINNACLE® Tube Development

Generation 3 PINNACLE® – See the ITT Night Vision PINNACLE® Image Intensifier Tubes for a good explanation of this commonly misunderstood advancement in night vision technology. See also: ITT Commercial Intensifier Tubes

Range is increased with later generations. In overcast conditions (0.0001 lux) a generation 1 device can recognize a person at 100 yds, with a generation 2 device that distance increases to 150 yds and finally to 200 yds for a generation 3 device.

Now you may get a generation 1 device and be quite happy at night, but only with a good amount of moonlight. Its not until you get very dark nights that the differences in generations becomes more apparent.

 

Combination Thermal Imaging & Image intensifiers

This from VEI show a Night Vision Camera with Image Intensifier and Thermal imager.

The cost however this unit is one of the cheapest on the market and yet is $12,000 plus.

 

Features to look for

Monocular or Binocular

Many of the least expensive night vision devices are monocular types. These can work very well and take up less storage space and can be kept conveniently in a pocket. It will take a little getting used to looking through one eye, but a monocular can prove to be very handy

Binocular types have one objective lens and one image intensifier tube. Even though you are looking through two eye pieces there is only one image intensifier tube. Therefore you are looking at the same image in each eye piece doing away with depth perception. Binocular types may be better for some as they feel and handle like binoculars, even though they are not.

There are binocular types with two image intensifier tubes, but at a much higher price.

The other type is the Silence of the Lambs type of a night vision device you can strap to your head. This device may be a bit disorientating however.

Other important Features to consider;

  • Performance characteristics of NV devices are sensitivity, SNR and resolution
  • Sensitivity or photoresponse is measured in microampere per lumen. Sensitivity measures the ability of the image intensifier to detect available light.
  • SNR is the signal to noise ratio, and measures the light signal reaching the eye, divided by the noise. US military standard for SNR is 20 minimum.
  • Resolution is the ability to distinguish between objects. Resolution is measured in line pairs per millimeter (lp/mm). US military standard for resolution is 64lp/mm.
  • Gen 1 cheap but needs some light to work.
  • The generation 2 picture is several times better than a generation 1 picture in very dark conditions, so to find out which is for you you should try them in similar conditions to that which you operate in.
  • Most NV devices use a IRI (infrared illuminator) to add a supply of light in extreme dark conditions.
  • Waterproof and ruggedness are important to boating use in the Marine environment.
  • When you use the night optics you will need to push buttons switches. Practice this in daylight so you know where they are.
  • Read this instructions on how to use the device and focus your eye. Most suggest you adjust the eyepiece first to get used to the eyepiece focus. Lens caps of Night Vision optics have small holes or filter in the center to facilitate this. The idea is in daylight you can look through the filet or hole and adjust the focus of the eye piece and then remove the cap in darkness.
  • What kind of batteries do the devices use so you have spares. AA batteries are simple cameras batteries are more difficult to replace.

 

Manufacturers of Night Vision

FLIR First Mate

The First Mate MS is the latest Handheld thermal night vision camera from FLIR. With this small monocular style camera you can see clearly in total darkness. The thermal imaging from FLIR lets you see in the dark for navigation or spotting a man overboard. It has also been noted that you can even use it to detect leaks in your refrigerator.

SM-3DB is a Day/Night Vision Binocular

specifically designed for use in marine applications. The digital night vision binocular uses CCD technology and can be used at night and day in bright sunlight without damaging the device.

The SM-3DB Series comprises 3 models; 8x, 11x and the Vario with 0.6 – 8x magnification. The SM-3DBs electronic accumulation & signal multiplication system, helps provide the best image. A high powered IR Illuminator is supplied as standard for viewing in complete darkness.

The Video Shows the images seen at night with a SM-3DB8 (without the IR illuminator) recorded via video output to recorder. The far side of the harbor is approximately 380 meters away. It is pretty cool to be able to capture the images to play back later.

 

ATN Image Intensifiers

NVM14 3rg generation Night Vision Monocular waterproof $2,995.

The NVM14 is a small waterproof and light monocular with great reviews. Suitable for boating use the 1:1 magnification and single AA battery with rugged construction.

5.5 inches, 11 ozs, 40 degree field of view.

Yukon
Yukon

 

Yukon

This Generation 1 Waterproof night vision Monocular from Yukon is a cheaper option retail around $350.

 

Fujinon 12 X 40 with gen 2.5 night vision

These must be very cool to have if you have the money. The Worlds ONLY High Power, Internal Gyro-stabilized Binocular 2.5 generation Night Vision Binocular, Waterproof and Buoyant. $14,995

 

Conclusion

These are fun to use plus they can offer specific navigational benefits. Try out any night vision devices beforehand as you may spend a small amount and get disappointed or spend too much and get no additional benefit depending on your circumstances.

Do not confuse Night Vision Binoculars with magnification. They are intended to show you a night image not magnify the image. Note the magnification number in the specs of the device you are looking at. Single tube devices do not provide depth perception.