Compared to what, when and where...?
Leica Ultravid HD Plus 7x42 vs Swarovski SLC 8x42 vs Leica Noctivid 8x42 vs Leica UVHD+ 8x32...
22-9-2021, more added 14-11-2021
Returning to Iceland for a film project I had the pleasure of comparing an all time favourite, the Leica Ultravid HD+ 7x42 - the very sample I used to own and which I sold because the Zeiss Victory FL 7x42 seemed more exciting - to my workhorse, the Swarovski SLC 8x42.
First impression: Damn, now I need to get that Leica glass again. What a gorgeous image.
In direct comparison though, the Swarovski seemed to be technically the superior optics:
- images looked brighter
- colours seemed more neutral instead of orange as in the Leica.
- edge performance was slightly better
- field of view felt much wider in the Swarovski than the difference on paper, which I attribute to the better off axis correction of the SLC, which is also a possible reason for
- a more immersive image in the SLC.
On axis, both glasses had superb contrast and sharpness, but the Leica seemed quite a bit darker.
Take home message: Never underestimate Swarovski. They are the leading manufacturer of binoculars, no doubt, and the SLC optically is a great binocular.
Shame though the SLC does not have a mechanical and industrial design rivalling the Leica and doing justice to its optics. The Leica is better mechanically, and much more attractive. A real classic. The new owner says she is never going to part with it.
Moreover, let´s consider the where and when, too. Iceland, always close to the sea, and a lot of sunshine - that means a lot of blue light, reflected from sky and sea, which makes the blue cut off in the SLCs transmission curve less conspicuous and the image look neutral instead of slightly yellowgreen as the transmission curve would suggest. Moreover, not many red subjects, so no obvious issues with the reduced red spectrum in the SLC transmission curve.
Ester Rut Unnsteinsdóttir, world expert on Arctic foxes, mammal ecologist at the Icelandic Natural History Institute, protagonist in my film "The Fox Whisperess", and happy owner of a Leica UVHD+ 7x42.
Autumn at home, a good time for direct comparisons in the garden, having a break from my work in postproduction. Last roses, last flowers, and a lot of yellow, orange, red leaves in the landscape.
I really love to use the plants in my garden for binocular testing. They provide the full spectrum of colours, combined with a 1000 shapes and a lot of textures of all sizes.
I do a lot of close up observation, but can cover all distances with a church tower about 500 meters away.
I use the SLC 8x42, the Nikon EDG 8x42, the Noctivid 8x42 and the Leica UVHD+ 8x32 in direct comparison.
The problem about colour rendering in binoculars is that the designers have a conflict here, especially when designing a glass for nature observation, not hunting. They need to decide between colour accuracy and a perceptual boost in contrast and brightness by skewing the transmission curve and introducing colour casts.
A green or yellowgreen cast increases the perception of both contrast and brightness. This "glow effect" can be really amazing, especially in low light. I saw it best in the Zeiss Victory FL 7x42 (green cast) and Swarovski SLC 8x42 (slight yellow-green cast) compared vs. the Leica 7x42 UVHD+ (yellow with a touch of red). For hunting glasses, this colour inaccuracy absolutely makes sense and they will be harder to sell without it. This "glow effect" probably in combination with high contrast of textures is what I wrongly called "high transmission sparkle" in 2015.
Zeiss has always been heavy handed with their green cast and unfortunately continue to do so in their SF line, which is advertised as being designed for nature observation, where colour accuracy should be important. I can´t force them to be more subtle, and they can´t force me to buy their stuff. Fair enough.
The SLC uses a well balanced slight yellowgreen cast to great effect, the contrast and especially the brightness boost are amazing. Well balanced because the predecessor seemingly had a stronger cast (see transmission curves on allbinos). Swarovski used to advertise the SLCs as "contrast optimized". I would avoid older Swarovski models, as most of them had a strong yellow green cast being contrast optimized for hunting.
I perceive the SLC as the brightest 8x42 with SP prisms. The disadvantage is that the image lacks in blue and red, whereas the Ultravids deliver full red. This is very noticeable in autumn landscapes. The Ultravids still have a bit of "glow effect" from their yellow cast compared to more neutral glasses (Swarovision, EDG). For my taste, this is the sweet spot of colour rendition and contrast in binoculars, and this autumn proved it again and again.
But compared to the SLC, the UVs seem to have a darker imagery, because the "glow effect" is reduced. With the SLC, I always think the image is even brighter than what I see with naked eyes, with the UV7x42HD+ or 8x32 I always feel it is a bit darker.
The Nikon EDG and Swaro SV are more neutral, neither cutting of a lot of blue nor red. This can be very beautiful, especially in brighter scenes, but in low light they lack any "glow effect". I have a rose with creamy pink flowers, it looks most gloriously natural viewed through the Nikon EDG, but it does not glow in twilight with the Nikon.
The Leica Noctivid in my view has introduced a bit more green compared to the Ultravids, giving it a stronger glow in lowlight at the expense of magical Leica reds. They could have pushed much harder, like the SLC, but colour accuracy was obviously more important. I can assure you that the SLC images look much brighter than the Noctivid in low light. The Noctivid is a very good compromise colourwise, but that can´t be fully appreciated due to other issues (flat field, diffuse flare).
The Leica Geovids definitely have hunting coatings with a green cast in the image, which makes total sense.
- I just came back from 20 minutes observation in the garden, in the blue hour. The SLC glowed most, seemed brightest, but clearly desaturated the oranges and reds. The colours just did not feel quite right. The Nikon EDG view was compelling with neutral colour and impeccable contrast and transparency. The Leica 8x32 had worst ease of view due to the smaller exit pupil, but the balance of warm colours and a slight glow was striking again.
Interestingly, Swarovski tried something else with the NL Pure: Neutral colour with highest transmission. It will be interesting to see how this works out, but I bet against it. You can´t get a strong "glow effect" with neutral colour, and a small percentage of more brightness will be hardly noticeable.
I appreciate the SLC more in low light and blue light, as it is hands down the brightest glowing 8x42 available new and the very best 8x42 for hunting - the Zeiss Victory FL and HT are no longer produced. Very bad move from Swarovski.
My love for the Leica Ultravid line remains. 7x42, 8x42 and 8x50 are high on my wishlist.
A very nice nice dwarf sunflower blooming in October 2020. Unfortunately it was short lived. I need to try again.