Having the capability of measuring distances through binoculars is not a new concept - I read with great interest about rangefinder binoculars in articles more than a decade ago. But the recent breed of laser rangefinder binoculars appeared to be exclusive to high-end European manufacturers so with a premium price to match were well out of reach for myself and the average hunter.
Kahles have released their affordable rangefinding binoculars, the Helia RF 8x42 and Helia RF 10x42, and David Duprez of Kahles Australia loaned me a pair of the latter for review. Being one of the world’s oldest optics manufacturers, Kahles are familiar to Australian shooters and it would be hard to find an old roo shooter’s rifle that wasn’t topped with a fixed power 8x56 scope.
A professional roo shooter mate of mine has two of them and uses his 15-plus-year-old Kahles scopes to this day and reckons from all the years of being knocked about in his cruiser they haven’t let him down.
Out of the box
The binoculars came supplied with a custom-made Waldkauz brand leather and woollen felt neck-strap and protective lens covers. It’s hard to fault Kahles’ effort to present their product and for those who don’t have a binocular harness the leather neck-strap would do the job but it’s more suited to the bird-watcher than serious hunter.
Out of the box and in the hand you’d expect binoculars with all their inbuilt electronics to weigh a substantial amount but at 880g it’s a negligible difference compared to the ‘non-rangefinder’ binos I’ve carried for the past 12 years.
Unlike others available, Helia RF binos are not an open bridge design but this doesn’t detract from their overall feel. Most of the rangefinding electronics are housed in the closed bridge and the power on/measure-and-mode buttons are accessed easily on the top right of the bridge. I have ‘ape-like’ fingers but the grip and feel to me is comfortable. The centre focus wheel is easily found in the middle hinge section of the bridge with dioptre correction adjustments on the ocular lenses. Both eyecups are click adjustable by twisting them anti-clockwise.
There are three additional positions available to set for your correct eye relief. Interpupillary distance (single image) is adjusted by hinging the barrels to suit the operator’s eye width. The binocular chassis and lens barrels are made of alloy and the external surface coated in a durable rubber with integrated grips, making it easy and firm to grasp. This is an important consideration in harsh weather conditions.
Unlike Kahles’ European competitors, Helia RF binos are predominately brown in colour and blend in well when hunting camouflage is important. The lenses are sealed within the barrels and purged with nitrogen for water resistance and to prevent fogging.
The nitty-gritty (electronics)
Most people are privy to how a laser rangefinder measures distance but it’s important to note Kahles quotes a realistic rangefinding minimum of 10 yards to 1600 yards - or 10m out to a maximum 1500m - as opposed to a competitor’s advertised 1500 yards, a slight but handy advantage of around 150m. The distance display can be altered from yards to metres using the mode setting.
The Helia RF binoculars also include a ballistic mode or what Kahles calls EAC-function (Enhanced Angle Compensation) that takes into account the target angle and distance, providing a realistic target range measurement for the hunter.
A scan mode enables you to have updated measurements as the binoculars are scanned across the target area, an advantage when following a moving target. For instance, when a target pulls up momentarily you can make an informed decision as to whether it’s still within your capability to shoot or not.
All the head-up display of the modes and rangefinding is lit in red and located in the right-side eyepiece with the aiming mark occupying the centre position. The brightness of the display is adjustable to five levels in the mode setting and can be altered depending on ambient light. This was evident during field testing and as daylight began to fade I dropped the brightness setting and it didn’t interfere with the view of the object I was observing.
The sharpness of the head-up display is corrected using the dioptre adjustments and information on all necessary alterations are in the supplied user manual. These electronics don’t come solar powered and like all their competitors the Helia RF binoculars are powered by a CR2 battery.
While the lenses are of a high standard they’re not made in Austria like previous Kahles binoculars. The Helia RFs are made in China, a strategy to provide a premium product at a more achievable price than their close competitors. This didn’t deter me as the binoculars I’ve used on many hunts and paid well over $1000 for more than 12 years ago, have lenses made somewhere in Asia and I still can’t fault them optically.
Kahles doesn’t have a fancy marketing name for their lenses but they’re coated to provide superior light transmission for hunting in all conditions as was evident during my field testing. A field of view of 59 degrees from the 42mm objective lenses allows for a broad area to be observed.
In the field
Before I went hunting with the Helias I mounted them to a harness with protective pouch that sits comfortably on the front of my chest. Being a loan item I was conscious of my responsibility to return them as close to new as could be expected.
Before my annual red deer roar hunt I took the Helia RFs to the range on a friend’s property close to home where I was able to familiarise myself with the functions, rather than messing around on an important stalk. Setting up targets for sighting-in, the rangefinding binoculars proved their worth as I sat back and took ranges at other objects around the countryside with ease. By keeping my finger on the range button and scanning the binoculars across the landscape, the display was rapidly updating me with distances of various targets, reinforcing the Helia RF’s specification of laser/range reading processing speed of 905 nanometres (+- 10nm). Put simply, super fast!
The furthest range taken freehand was 1215m ‑ a vast improvement on the old RF monocular I’ve owned for years. I suspect to reach full range-reading capability of the Helia RF’s claimed 1500m would require the aid of a rest such as a pack and a ‘binocular tripod’ would be a handy addition (there’s has a screw port for a tripod adaptor in the front of the hinge section).
The impending roar came with much anticipation and I couldn’t wait to put the RFs to the test in a real hunting situation. As with all hunts the weather can be unpredictable and while our first day was fine it went downhill from there. The rain wasn’t going to stop us from looking around, so my son and I stepped off from camp to check for sign. Apart from the usual external fogging common with all lenses in rain, moisture was easily wiped away.
The lenses pierced through gloomy conditions giving a clear image and I was able to successfully take ranges in the thick scrub to distances of around 120m. But I found that mist hampered the ranging performance of the binoculars, when the mist disappeared the ranging was back on but as soon as another cloud swept through, ranging was affected again.
On further investigation back home, the user manual does state that misty conditions will affect the range-finding ability as does bright sunlight and snow. I’ve been reliably informed this is not unique to Kahles, as most models of laser rangefinder are similarly affected. Anyway, the sky cleared and with the aid of the Helia RFs I secured a large mature red stag on a steep slope.
As expected of a Kahles product they performed admirably, the look, feel and functionality of range-finding and quality of the lenses making glassing a breeze and the EAC gave an accurate actual range to allow for when shooting in mountainous terrain. The Kahles 8x42 and 10x42 Helia RFs are great pieces of hunting kit, manufactured to a high standard and both retailing for $1990, a fraction of the cost of other similarly capable models. They carry a 10-year warranty on mechanical parts and two years for electronics and service. More at kahles.at or email [email protected]