In the strong sunlight of high altitude you need decent category 4 sunglasses. But what about when it's overcast at lower levels? Here's where a photochromic lens comes into its own, changing to suit the available light. Becky Coles and Simon Verspeak have been putting these men's and women's shades from Julbo to the test in a variety of settings from the sunny UK to the rainy Alps, and from the Nevada desert to the Himalaya.

Monte Bianco with Cameleon Lens - Simon

Spending long days outside soon makes you realise that even on gloomy days you sometimes require sunglasses to protect your eyes. Glare off snow or water quickly tires your eyes and over time I have realised that despite their obvious advantages if you break them or lose them, cheap sunglasses simply don't have good enough lenses (also since having had laser surgery to correct my vision I am more aware of the need to protect my eyes). Therefore I believe investing in good sunglasses is essential.

This is the second pair of Julbo Monte Biancos I have had and once again I have tested them to the max, from rock climbs and hill walks around Britain, and big routes and ski tours in the Alps, to the desert states of the US and high altitude peaks in the Himalaya.

Frame

From the very first moment I put these glasses on my head they have been comfortable. The arms sweep back, enclosing themselves around your head. I also like that they have small holes in the ends of the arms allowing you to add a small piece of cord or elastic to help with keeping them in place. This is something I did very early on and has made a real difference to both comfort and retention on my head. Removable side shields allow you to tweak the level of protection depending whether you're basking in the UV of the high mountains or back down in the town.

Lenses

Both the Monte Bianco and the Monte Rosa come with the choice of either a fixed lens cat 4 or a photochromic option. We had the top of the range mountaineering-adapted Cameleon lens, which is also polarising. This is the part of the glasses which has most impressed us. The Cameleon lens is a clever concept, adjusting the protection of the lens by polarising photochromic technology to change from category 2 protection to category 4 depending on the strength of the sun. These adjust extremely fast when moving from shade to sun; however, they seem to change more slowly the opposite way. This is easily rectified in most cases by pushing them for a minute or so on to your head to let them reverse, but it's something to be aware of when you're out in conditions of high contrast.

Accessories

The glasses came complete with a hard case and a soft bag. The case is a really good idea; I have lost glasses, even dropped them in lakes, but the main danger seems to be sitting on them in my bag.

Verdict

A mark of a favourable test is whether you would spend the money to purchase the product yourself; in this case I certainly would. These are are a great versatile product for use in the mountains and for me this versatility is largely in the Cameleon lens system. I'd highly recommend any of Julbo's glasses that offer this option.

What Julbo say:

Monte Bianco – from Mountain to Valley

A great classic for mountain lovers on familiar terms with the peaks… but who also return to the valley! Ideal for medium to large faces, the removable protective side shields offer perfect adaptability to climatic conditions. Lightness, technical excellence and high protection are combined with style and simplicity on this model.

• Price: £140 with Cameleon lens; £65 with Spectron 4 lens; £105 with Zebra lens (available 2017)
• Weight: 32g
• Cord attachment holes
• Curved temples for good hold on face and head
• Removable side shields
• Grip Tech - flexible inserts adhere to the temples for maximum hold and comfort
• The frame can be equipped with corrective solar lenses

Choice of lenses:

• Cameleon 2-4 photochromic: This polarizing, anti-fog and photochromic (cat. 2 to 4) lens is ideal for mountaineering, ski, etc.
• Spectron 4 polycarbonate: Cat. 4 lens with flash +AR coating. It is suitable for all sports where there is exceptionally bright sunlight.
• Zebra 2-4 photochromic: Available in the UK 2017: This photochromic (cat. 2 to 4) anti-fog lens is ideal for mountain biking, trail running, climbing, cross-country skiing, etc.

For more info see julbo.com

Monte Rosa with Cameleon Lens - Becky

I'd not owed a pair of white framed sunglasses before; it was like I'd never been part of the outdoor instructor fraternity. These sunglasses turned up and suddenly I had the ability to strut, look down my nose at the knots people were tying at the crag and have the right to jump the queue beneath classic routes because, obviously, I'd climb faster.

So, the colour of the frames was a winner to start with, and the fact that they fit my pea head really well. The lenses are also very dark, therefore obscuring my inner thoughts when assessing people's belaying. These glasses came with the new Cameleon lenses which were superbly clear. They adapt to the brightness of the light and were very easy to wear. The only problem I did have with them was, when I'd put them on my head, maybe to emphasise my disapproval of their gear placement or if I thought someone needed to see my eyes because they looked like a particular dim-wit who couldn't possibly comprehend an instruction unless I did so, then once I'd slide the glasses over my eyes again they'd be very dark, rendering me with a sight impairment until they adjust.

I had much experience of wearing them in darker conditions as, whilst the UK basked in glorious sunshine, I was in rainy, cold Switzerland. There sunglass wearing conditions were pretty marginal but, being a dedicated gear reviewer and on my first assignment for UKC, I battled on. And in my experience, just as in Simon's, the Cameleon lenses do seem to take a little time to adapt from light to to darker conditions. This leads to either the risk of walking into something and as such undoing all the cool that you gain from wearing white framed sunglasses, doing the eye/head shuffle with the glasses, again not cool, or, what I ended up doing, putting them in a pocket to get them to lighten before putting them on.

To be honest the changing speed of the lenses from dark to light was pretty minor and won't stop me buying them. What might get on my nerves however is that though the Cameleon-lens version are predominantly white framed, Julbo just couldn't help slipping a little ickel bit of pink in them. Then with this ickel, wickel pink is also a lovely, wovely bit of lilac. Am I annoying you yet? I'm annoying me. Which is how it feels to be a woman in the outdoors when your only choice of clothing and equipment is in pink or purple or both! Some less 'feminine' colour frames are available, but only with the Spectron 4 lenses.

What Julbo say:

Monte Rosa – Feminine from Peaks to Streets

For those ladies who explore the summits yet also enjoy the hustle and bustle of urban life, Julbo presents the Monte Rosa. With removable shields, high protection lenses and a curved ergonomic shape, the MonteRosa offers adaptability, versatility and complete protection.

• Price: £140 with Cameleon lens; £65 with Spectron 4 lens; £105 with Zebra lens (available 2017)
• Weight: 29g
• Cord attachment holes
• Curved temples for good hold on face and head
• Removable side shields
• Grip Tech - flexible inserts adhere to the temples for maximum hold and comfort
• The frame can be equipped with corrective solar lenses

Choice of lenses:

• Cameleon photochromic: This polarizing, anti-fog and photochromic (cat. 2 to 4) lens is ideal for mountaineering, ski, etc.
• Spectron 4 polycarbonate: Cat. 4 lens with flash +AR coating. It is suitable for all sports where there is exceptionally bright sunlight.
• Zebra 2-4 photochromic: Available in the UK 2017: This photochromic (cat. 2 to 4) anti-fog lens is ideal for mountain biking, trail running, climbing, cross-country skiing, etc.

For more info see julbo.com