Let there be light – actually, we don’t need it

Pete Kincade

Pulsar Accolade XP50 thermal imaging binoculars are distributed in Australia by ExtraVision, the same firm who handle Vortex optics and the first to supply thermal imaging products to the Australian market back in 2010. The Accolade series of thermal imaging binoculars, monoculars and telescopic sights must be experienced to be believed. I had the chance to use a set of these hi-tech wonders and am convinced that for culling of feral animals they’re superior to traditional spotlighting methods, but more on that later.

History lesson

To put thermal imaging binoculars into perspective, let’s briefly review the history of telescopes.

Holland 1608: Hans Lippershey invents the telescope and builds the first binoculars later that year.

Italy 1609: Astronomer Galileo develops a telescope that uses convex lenses for the objective and concave for the eyepiece, his first working model of 8x magnification.

England 1704: Sir Isaac Newton devises a radical concept in telescope design. Where others are using glass lenses, Newton uses a curved mirror which reflects incoming light back to the point of focus. This approach ‘collects’ light and sends it to the eye. By increasing the size of the collector, more light can be captured and light transmission efficiency increased.

Scotland 1740: James Short develops the ‘Short’ telescope, a significant advance. An optician and astronomer, he devises a distortion-less, parabolic and elliptical mirror, solving the problem of distortion which has plagued developers since Newton.

England 1800: Astronomer Sir William Herschel is an exception in the history of looking at distant things, famous for discovering the planet Uranus but less well known for discovering the electromagnetic spectrum or what we know as infrared. While Lippershey is the daddy of binoculars, Herschel is the daddy of thermal imaging.

Italy 1854: Ignazio Porro patents his prism system for binoculars and telescopes. His memory lives on in every set of porro prism binoculars.

No light, no image

Binoculars let us see into the distance and are an invaluable aid to hunters for spotting and identifying game and non-game animals. However, conventional binoculars and spotting scopes, regardless of whether they’re porro prism or roof prism by design, have one thing in common – they transmit light which passes to the viewer’s eyes and is translated into colour and shape in our brain. No light, no image. Conventional light-gathering optical devices don’t let us see much of anything when its dark so when its black it may as well be nothing.

How do they work?

Unlike conventional binoculars the XP50s don’t rely on light that can be seen by the human eye and while they’re very effective in daylight, their primary role is night-time use. Instead of capturing rays of human visible light, these thermal imaging binoculars do just as their name suggests, receiving and decoding heat energy (infrared radiation) that we see as shapes we understand and shows them on its high-contrast AMOLED display.

All living things emit infrared energy as heat and Pulsar Accolade XP50s detect even the slightest differences in temperature of objects and scenery. They enable you to literally see in the dark, even total, pitch-black darkness. I’ll forgive you if you don’t believe me but when it comes to using them, seeing really is believing.

The XP50 caters to all viewing conditions with an eight-colour palette, the most versatile mode being ‘White Hot’ though during night-time review I mostly used ‘Hot Black’. According to Pulsar this mode is “often favoured for detecting wildlife at night. Red monochrome helps reduce or prevent bright backlight from exiting the eyepiece. Sepia often improves long-range observation while ‘Red Hot’, ‘Rainbow’ and ‘Ultramarine’ enhance temperature differences of various object attributes. Violet helps identify objects faster”.

Pulsar developed thermal imaging equipment for the law enforcement market before recognising their application for sporting purposes. For the efficient and humane culling of feral pests, the potential of Pulsar thermal imaging equipment is undeniable.

Spotlighting of pigs, dogs, cats etc only lets us see a fraction of the number of animals within the arc and range of even the best spotlights, which can also alarm quarry and cause it to go to ground. My experience with the XP50s was amazing and providing I was mindful of the wind and maintained stealth, I could observe wildlife indefinitely.

The XP50s are built around an infrared sensor, intuitive in operation and have features which let the user capture digital stills and video. There’s 8GB of built-in storage providing up to 150 minutes of video or almost 10,000 images, downloading video and still images done via micro USB interface to your PC, Mac or Linux computer. While their primary purpose is night use, they can also see through serious weather such as snowstorms and heavy fog.

Unlike earlier generations of night-vision equipment, no external source of infrared light is required which may explain the excellent run-time from the rechargeable 3.7-volt Lithium Ion battery, Pulsar claiming run-time of seven hours on a full charge.

I gave the battery a complete charge and never recharged it during the night I reviewed it, running it for several hours and switching off during travel. If you need more than seven hours, Pulsar offer longer-charge Li-ion batteries which last up to 24 hours.

The XP50s have features in common with conventional binoculars such as dioptre and interpupillary adjustment, the former done in the same way as conventional binoculars, focusing via a central ring. Because they have a single sensor for both eyes, the need for two ‘barrels’ as in conventional binoculars is eliminated, nor is there any requirement for a central hinge as in roof prism binoculars.

While I didn’t go out my way to abuse them, when not in use they bounced around the front box of my Polaris 4-wheeler. They look and feel very strong and Pulsar’s reputation for supplying law enforcement with high-end thermal imaging kit is testament to their rugged construction and weather proofing. The sealed non-reflective polymer body has an IPX-7 waterproof rating and can endure a depth of up to one metre for 30 minutes.

The XP50 has a single Germanium objective lens, interpupillary adjustment done by merely sliding the eyepieces inward or outward to suit. The unit doesn’t have fold-down eyecups, rather soft rubber shields on each eyepiece to ensure no ambient light enters your viewing area, and as I wear glasses I simply folded these to the side. With a super-generous 16mm of eye relief, these are suitable for using with or without specs.

Optical zoom is 2.5x and digital zoom enables 2x, 4x and 20x magnification and I found images to be crisp and clear once I understood the importance of calibrating the sensor for each viewing session. Calibration is easy, merely close the hinged cover over the front lens and toggle the power button with a short press. Once calibrated, open the flap and start scanning.

Image resolution is 640 x 480 pixels and results in the highest quality at all distances. I found image quality a real advantage when looking for game in thick-with-oats paddocks, thermal detection 2000yds or 1829m. They come with a nylon carry pouch and shoulder strap, one Lithium Ion rechargeable battery, usb cable and charger and comfy neck strap.
Operating the unit is easy. The onboard 2.4Ghz wireless card lets you stream vision to your smartphone or tablet up to 15m away. On the underside is a 1/4-20 UNC embedded fastener for standard camera tripod mounting, handy for capturing digital stills and video. The stills shown in this article were taken offhand and don’t do justice to how sharp the vision is.

The XP50 under review didn’t include a Laser Range Finder which is available as an optional extra but stadiametric range finding is included and assists range estimation to an animal based on its size, the stadiametric display gradient pre-calibrated for hare, pig and deer.

Conclusion

Until you use a thermal imaging binocular or scope you really don’t know what you’re not seeing, literally. At first I wasn’t expecting much but you can’t find what you can’t see and compared to spotlighting for pests at night, thermal solutions are the way to go. Animals are not disturbed as with spotlights and more likely to be found out of cover. Hunters must still be mindful of stealth and wind when searching for game, but results are likely to be better than with a spotlight. If the game is there and you’re mindful of your hunting craft you’ll find it.

Something which became obvious after using the XP50s was just how much night shooting safety is increased. I could see not just the animals I was after but stock in the background, machinery and outbuildings near to and behind the game. Compared to spotlight culling I was enjoying a safer shooting experience.

Pulsar Accolade XP50 thermal imaging binoculars are clearly a high-end and rugged 50Hz piece of kit for night-time cull-hunters. When combined with a thermal imaging scope I believe they’d be phenomenal for efficient and humane eradication of all feral game.

These are not cheap and will be out of reach for many of us. The ExtraVision website lists a retail price of $7500 but an online search revealed Australian retailers listing them at prices which make them far more affordable.

If price is not an issue you won’t be disappointed. Head into the dark bush at night with these and you’ve put the odds of connecting with feral game firmly in your favour.

All News