Reviewed by Brian Mullin https://www.gramslightbikes.com/
I have been putting the Julbo Dirt sunglasses through the paces from close to a year now while mountain biking. They have dealt with wind storms, rain, snow, and light varying from the bright desert, to the dark woods, and everything in between. They have gotten bounced around while riding through rock gardens, ridden at Mach 1, been dropped on the ground a number of times and been worn under assorted helmets (even full face). They have turned out to be comfortable, durable, fog free, and offer excellent wind protection, great varying light capabilities and superb optical clarity.
Julbo was founded in 1888 by Jules Baud in a little town close to Morez France, which resides in the Jura Mountains. The company has 70 employees, and is wholly owned by the Baud family, and is currently run by the brothers Christophe and Matthew. They originally started out making optical (corrective) lenses, but they evolved into sunglasses and action sports wear. In 1950 Julbo was the first company to produce true mountaineering glasses (the Vermont Round), so they have a rich history in high altitude optics.
The Julbo Dirt is a bit of a departure from the average sports eyewear, and instead of the atypical thin or skinny frame, its built beefier, with a very wide section by the hinge and temple, which offers additional side protection from sunlight. The hinged wraparound frames have a nice sculptured curve, and has soft rubber shock absorbing material for the nose and ears, offering grip while doing athletic movement. They mainly come with the Zebra lens made from the indestructible NXT, which offer anti-fogging, impact resistance and light-sensitive Photochromic features. They also comes with a nifty hard case to carry, and protect them. The Dirt come in several versions and colors, the Zebra (NXT, Photochromic 2-4, Antifog) in White, Black, and Chocolate, the Camel (NXT, Polarized, Photochromic 3-4, Antifog) in Khaki and the Polarized 3 in black. If it's required, you can order them with corrective lenses.
Weight: 40 grams (1.4 ounces)
Lens size: 65mm x 40mm (2.5 x 1.5 inches)
Arm Length: 71mm (4 3/4 inches)
Frame Width: outer 145mm (5 3/4 inches) inner 130mm (5 1/8 inches)
Zebra Photochromic Lens
The Dirt's use Julbo's Zebra photochromic lens made from the unbreakable, lightweight and very transparent NXT. They quickly darken with a light brownish tint or lighten with an amber tint depending on light intensity, and have an anti-fog coating that has been laser etched into them. Per Julbo fodder "adapts to varying light conditions from Category 2 (59-percent visible light coverage) in low light conditions to Category 4 (95-percent visible light coverage) in powerful light in as little as 30 seconds".
The NXT polymer technology was born of the successful efforts to develop advanced transparent armor for U.S. Army helicopters. Commercial applications for the new transparent polymer material led to the production of lenses and shields for sunglasses and sport eye wear. The NXT lens is manufactured by pouring resin into a low-temperature glass molds. This reduces the tension in the material and gives better optical quality, excellent transparency and improved long-term stability. The NXT lens meets the ANSI Z87.1 standard for industrial application impacts, meaning it must withstand a pointed 17.6 ounce projectile dropped from a height of 50 inches, and 1/4 inch steel ball traveling at 150 ft/sec! I did not test either compliance, but I am glad it can take a wallop. Julbo lenses offer 100% protection against UVs: UVAs, UVBs, and UVCs.
For some in-depth fodder on Sun and Eyes, refer to https://reviews.mtbr.com/blog/sunsunlight-101-and-human-eyes-101/
Next » Impression
What I really like about them is the full coverage they offer, giving good field of vision, aerodynamics and excellent wind coverage. I do hate eyewear that makes your eye water when you go ride into a strong headwind, or when you start to boogie going downhill. The Dirt offer incredible wind protection, almost like wearing a pair of goggles. I think wind protection is due to the large lenses, wrap around frames and that they sit close (but not to close) to your face.
Another per peeve is lenses that fog up on you, like when you go into a dense section of trees that might be humid, after a rainstorm, or when you start sweating, and then pop into a cold spot on the trail. The Dirt never seemed to fog on me in any of the adverse conditions that I dumped them into, so the anti-fog coating works amazingly well. The side sun coverage that the frame offers are quite nice, and cuts down on eye fatigue and scattered light entry, and the frame and lens curve around enough that the sides don't interfere with your peripheral vision. The curve and shape of the frame, along with rubbery shock absorbing nose and ear coverings, keep the sunglasses stuck to my head no matter how rough the terrain tossed at me. They fit nicely within helmets, but bow out a bit much for a full faced helmet. With any pair of sunglasses, I can never decide whether to wear them under or over the helmet straps? They have been comfortable, with a nice fit and feel. One issue is there is no adjustability since the frame is not pliable (stiff frames) nor offers any adjustment features.
Thanks to the durable NXT, the lenses have been bombproof, and I have gotten no scratches, which is pretty amazing, since I always seem to do that with any eyewear, even the ones that are supposed to be unscratchable (marketing hyperbole). They have excellent varying light capabilities due to the Zebra photochromic lenses, and the amber tint has been especially nice on the cloudy and foggy days. Sometimes buzzing in and out of trees in the bright afternoon sunlight the lens did not change fast enough for those conditions, but it is a very minor issue. If I was doing a lot of desert riding, or was going to be constantly out in bright sunlight, I might prefer a somewhat darker lens. I usually ride in places in which I am going in and out of the shade, into wooded areas, and I also ride a lot in the late afternoon, so I appreciated the photochromic lens. The lenses have phenomenal optical quality, and they're distortion free with a high degree of clarity. The lenses are large and curved enough for a nice panoramic field of view.
Next » Bottomline
They also look fashionable enough to wear around the pool, hot springs or about town without looking like an outdoor sports geek or even a roadie! Ok, I still look like a geek?
I really like the Julbo Dirt sunglasses, they are comfortable, stay put, have exceptional clarity, and offer excellent wind and side sun protection. The lenses' photochromic capabilities are great in varying conditions, while the anti-fog actually works in real world conditions. The durable, scratch and impact resistant NXT material is pretty amazing, and offers outstanding safety. The Dirt is expensive (like a lot of the competition), the frames are a bit stiff, and do not offer any method of adjustment. Julbo has a winner with the Dirt, and they are ideal for mountain biking, having many of the functional features that work nicely for this niche.
-Side sun protection
-Excellent wind protection
-Frames not adjustable
Overall Rating: 4 Flamin' Chili Peppers
Lens: Zebra - NXT + Photochromic 2-4 + Antifog
Color: White, Black and Chocolate
Lens: Polarized 3 / Lens
Lens: Camel - NXT + Polarized + Photochromic 3-4 + Antifog / Lens
Julbo Dirt url: https://www.julbousa.com/performance/dirt/