GSCI Advanced Photonics, Image Intensified Night Vision

General Starlight Co inc

Canada based GSCI develops and manufactures some of the world's most advanced image intensified night vision and thermal imaging equipment.

Each device is made to exacting standards, which is why they are chosen by many police and military divisions worldwide. The equipment is also widely used for hunting applications, giving the user excellent clarity, quality and continued confidence with a 7-year warranty.

Choosing the right product can be a minefield especially when there are so many different variations and complicated terms, so we're hoping to make this easier for you by explaining some of the basics.

More recently we have been finding a huge increase in GSCI units supplied by us to the hunting market, and it's understandable as to why these have become so popular given the incredible performance.

There are two stand out units that we advise for hunting, the PBS-14 and PVS-14C. These are handheld tubed night vision monoculars, which can be mounted to the rear of a parallax adjustable dayscope using a day scope adapter (DSA) to convert your scope into a night vision scope - very handy if you don't want to tie up a rifle to be a dedicated night shooting set-up.

GSCI PBS-14 NV Monocular - From RRP £2,229.95

The PBS-14 is a fantastic choice to use as a rear add-on, it is by far one of the best value for money rear NV add-ons on the market today - it uses a basic housing and lens to keep the cost down, but still offers the impressive image quality and nighttime sensitivity from the photonis tube.

GSCI PBS-14 Night Vision Monocular / Add-on

What makes the PBS-14 stand out from the cheaper digital rear add-ons is the incredible build quality and simplicity - it's lightweight (330g), rugged, waterproof (IP66) and you can expect up to 40 hrs from a single AA or CR123A battery (you won't see runtime like that from a digital unit).

Clarity wise, the picture is incredible - we recommend the GEN2+ (Green Phosphor) if this is going to be used scope mounted for hunting, with an additional IR for that little extra ID / eye-shine you'll see much further than you'll ever pull the trigger on a safe shot.

GSCI PVS-14C NV Monocular - From RRP £3494.95

If you're looking for the next step up, the PVS-14C is the upgrade from the PBS-14 - it uses a higher quality housing improving the waterproof rating (IP67), plus different optics that will give you better image quality and nighttime sensitivity. Besides these differences in the casings, the PBS-14 and PVS-14C are the exact same in terms of size / weight etc.

What makes the PVS-14C an upgrade in terms of image quality, is the higher end tube options available - realistically you wouldn't want much more than the GEN3 or GEN3+ if you're using this as a rear NV add-on as you may find the unit becomes too sensitive (depending on what day scope this is going on, we recommend a parallax adjustable day scope with a low amount of coatings on the lens).

    Ordering process

    All GSCI products are treated as a custom order item, each night vision or thermal imaging device is ordered specifically for you and to the specification that you have selected. In most cases, we are able to dispatch within 2-4 weeks, but some units may take longer depending on the variations in stock with GSCI in Canada (in which case, we would contact you with an accurate stock ETA).

    As each unit is made to order, payment must be made in full (or via 0% finance and accepted with the deposit paid) before we go ahead and order your unit with GSCI. 

    • Step 1 - Place and pay for your order (we can contact GSCI for an ETA, before placing your order).
    • Step 2 - We will then place your order with GSCI, and have the manufacturing process started.
    • Step 3 - We will then fill out any customs requirements and forms, to get this to us here in the UK (if this is being shipped internationally, we will email you over forms to be completed and returned to us with a copy of ID).
    • Step 4 - Once your unit is completed, GSCI will ship this to us (or to you directly, if this is being shipped internationally) which usually takes 3-5 working days.
    • Step 5 - The unit will arrive with us, which we will then ship to you, via DPD courier.

    Generations in Night Vision

    Image intensifier tubes are classed by generation (GEN) numbers assigned by the US Army's Night Vision Laboratory. Each GEN denotes a new contract or manufacturing process.

    • Generation I: It started with electrostatically focused Generation I tubes featuring high image resolution, a wide dynamic range and low noise.
    • Generation II: Introduced the microchannel plate for much higher gain in the 1980’s. The original image resolution was less than that of the first generation intensifiers but the gain was much higher.
    • Generation II+: Later advancements in GEN II technology brought the tactical characteristics of "GEN II+" devices (equipped with better optics, SUPERGEN tubes, improved resolution and better signal-to-noise ratios) into the range of GEN III devices, which has complicated comparisons.
    • Generation III: In the late 1980’s an Image Intensifier with a GaAs photocathode was developed showing an enhanced sensitivity in the Near-Infrared. In the late 1990’s GEN-III tubes with greatly improved performance appeared on the market.
    • Generation IV: U.S. Army Night Vision and Electronic Sensors Directorate (NVESD) is part of the US governing body that dictates the name of the generation of night vision technologies. Although the recent increased performance associated with the GEN-III OMNI-VI (and above) components is impressive, the U.S. Army has not yet authorised the use of the name GEN-IVWeaver Mounting System for these components. This means the term GEN-IV is used more as a marketing tool than it is valid terminology, often used to describe high-end GEN-III tubes with an autogating power supply.

    Image Intensifier Tube Options

    Below is a list of all different tube options available from GSCI and their FOM factors, on each of our GSCI product pages you can find tube options that are available for each specific model.

    FOM is an abstract measure of image intensifier tube performance, derived from the number of line pairs per millimetre multiplied by the tube's signal-to-noise ratio (Resolution x SNR).

    Therefore the higher the FOM, the better the image

    • MA1 (Green Phosphor GEN2+, Autogated - FOM 1250-1599)
    • MA1 WP (White Phosphor GEN2+, Autogated - FOM 1250-1599)
    • GA2 (Green Phosphor GEN3, Autogated - FOM 1600-1799)
    • GA3 (Green Phosphor GEN3+, Autogated - FOM 1800+)
    • EC (Green Phosphor Echo, Autogated + Manual Gain - FOM 1600-2000)
    • ECW (White Phosphor Echo, Autogated + Manual Gain - FOM 1600-2000)
    • XR5 (Green Phosphor XR5, Autogated + Manual Gain - FOM 1600+)
    • XR5 ONYX (White Phosphor XR5, Autogated + Manual Gain - FOM 1600+)
    • 4G (Green Phosphor 4G, Autogated + Manual Gain - FOM 1800+)
    • 4G Onyx (White Phosphor 4G, Autogated + Manual Gain - FOM 1800+)
    Available for Professional Use
    • EC Elite (Green Phosphor Echo+, Autogated + Manual Gain - FOM 2000+)
    • ECW Elite  (White Phosphor Echo+, Autogated + Manual Gain - FOM 2000+)
    • 4G Elite (Green Phosphor 4G+, Autogated + Manual Gain - FOM 2200+)
    • 4G Onyx Elite (White Phosphor 4G+, Autogated + Manual Gain - FOM 2200+)
    EC Elite, ECW Elite, 4G Elite and 4G Onyx Elite Tubes are available for professional use only, please contact us for buying information.

    We have found that for the hunting market the MA1 (GEN2+) has been by far the most popular choice for nighttime shooting - paired with an additional IR illuminator to stretch it's legs you really will be seeing everything that you need to see and more.

    How far can you see with Night Vision?

    The chart below shows the detection range of various tubes, in different conditions without any additional infrared (IR) illuminator.

    GSCI intensified tube range of detections

    Technical data and terms, what do they mean?

    Automatic Brightness Control (ABC)

    This electronic feature automatically reduces voltages to the microchannel plate to keep the image intensifier’s brightness within optimal limits and protects the tube.

    This is most apparent when rapidly changing from low-light to high-light conditions; the image gets brighter and then, after a momentary delay, suddenly dims to a constant level.

    Auto-gated Power Supply

    Auto-Gating reduces the duty cycle of the cathode voltage by rapidly switching the voltage on and off. It is a proprietary means to preserve the high MTF (Modulation Transfer Function) and resolution that is obtained at the full operating voltage while reducing the strain of high illumination levels on the image intensifier tube. This is done by reducing the average current coming from the photocathode.

    Auto-Gating constantly operates to improve the quality of the image, not only during day-night-day transition, but also under dynamic lighting conditions such as military/law enforcement operations in urban environment which define many of today's missions.

    Daylight Lens Cover / Daytime Filter

    Generally made of a soft plastic or rubber cap with a pinhole that allows a small amount of light to enter the objective lens of a night vision device. This should be used for training purposes only, and is not recommended for an extended period of time. Near field focus only usable in this fashion.

    Eye Relief

    The distance a person’s eyes must be from the last element of an eyepiece in order to achieve the optimal image area.

    Field-of-View (FOV)

    The width or spatial angle of the outside scene that can be viewed through the intensifier tubes measured laterally and vertically.

    Figure of Merit (FOM)

    FOM is an abstract measure of image intensifier tube performance, derived from the number of line pairs per millimetre multiplied by the tube's signal-to-noise ratio (Resolution x SNR).

    Therefore the higher the FOM, the better the image. It is difficult to have an objective measure of quality for a night vision device since it is intrinsically reliant on external factors such as available light and weather conditions. Therefore the FOM is universally recognised as a measurable value to adequately determine the performance of the image intensifier tube.

    Gain (in Night Vision)

    Also referred to as brightness gain or luminance gain; this is the number of times an image intensifier tube amplifies light input. It is usually measured as tube gain and system gain. In any night vision system, the tube gain is reduced by the system's lenses and is affected by the quality of the optics or any filters; therefore, system gain is a more important measurement to the user.


    The magnifying power of the lens. Four power (4X) indicates that the image will appear four times larger than if viewed with a 1X lens.

    Phosphor Screen

    A very thin layer of phosphor is applied to the output fiber optic system, and emits light when struck by electrons. The purpose of the phosphor screen is to convert electrons into photons.

    Sacrificial Window

    A clear glass filter assembly designed to fit over the objective lens of a night vision device and designed to protect the optics against physical damage (chips, scratches, etc).

    Variable (Manual) Gain Control (in Night Vision)

    Allows the user to manually adjust the gain control (basically like a dim control) in varying light conditions. This feature sets the PVS-14 apart from other popular monoculars that do not offer this feature.

    We hope this has cleared a few things up on something that can definitely be very complicated, but if you still do have any questions make sure to get in touch with us on 01535 610066 / 01535 611688 or email us on - one of our knowledgeable team will be more than happy to help with any questions you may have or advise on what would be best suited to your needs.