15-9-2015, last revision 1-12-2015

Test period: starting 21-04-15
Serial Nr: 39780402
Origin of sample: Zeiss Germany demo

The 8x42 HT is a Zeiss masterpiece and optically the best of the classic curved field 8x42 designs - which I came to prefer over the modern flat field binoculars. It is an outstanding binocular that embodies the legendary Zeiss brand better than the SF, as it is the most recent model in a long series of evolving designs. No other binocular in the comparative review has Abbe König prisms. Apart from edge sharpness the HT is optically as close to perfect as I ever had a binocular, with spectacularly sharp, contrasty, bright and naturally coloured images. I´m astonished how quiet, almost free from flares the view is even under difficult light conditions. If highest image quality and a most natural view is paramount, the HT surpasses the other five 8x42s I tested.

Mechanical quality

Body
The magnesium alloy body feels very solid, and the big double hinge has perfect friction. Weight is about 830g as stated by Zeiss.

Focusing
The focusing wheel has a very low but even friction, a good performance, although I´d prefer a bit of more friction. Length of the gearing is about two revolutions from infinity to close.

Internal blackening and baffling
look not as good as in the SF, but the.small false pupils don´t seem to have much of a detrimental effect, as flare suppression is state-of-the-art.

Eyecups
have three click stops - four positions. Quite frequently one would unlock and slip back a bit which was a hassle.

Handling
The glass is big, and needs to be held close to the front end, which means a long leverage. The much more compact shapes of the Ultravid and Nikon EDG or Swarovski SLC which I grip with my hands close to the face feel more comfortable to me. With bulky gloves the Zeiss HT would work brillantly though. There is no dedicated tripod adapter except the old, huge and expensive Zeiss universal adapter, but the much cheaper Leica Ultravid adapter will work well enough with the HT.

Industrial design
is futuristic with nice textures and more pleasing than in the SF in my opinion.

Optical quality

Contrast
is superb, from macrocontrast to sharpness to microcontrast at the textural level. Images have an almost surreal clarity, punch and sparkle, I´d say really the best of all samples in the 8/8.5x42 test. Sharpness is high across 50% of the field and then gently decreases towards the edges, just as in other classic curved field designs as the Ultravid and SLC. The Swarovision is about as sharp in the center and much sharper at the edges but does not have that lovely high transmission sparkle of the HT. The Ultravid may have even a slightly higher contrast with blacker shadows generally, but seems a bit less biting sharp than the HT. Then again, the higher brightness of the HT may make it look a bit less contrasty than the Ultravid! Anyway, the HT really shines on a dull day and in the twilight.

Resolution testing with the chart showed this glass to be really outstanding. So did contrast check at 3x boosted magnification. Resolution at open aperture was 3.79 arcseconds at 8.56 m distance, and 4.06 arcseconds at 4 meters distance from the chart, surpassing the DIN ISO 1433-2 norm of 5.7 arcseconds by a good margin. Resolution with objectives masked to 20mm (2.5mm exit pupil size) was 6.77 arcseconds at 8.56 meters distance and 6.44 arcseconds at 4 meters distance as with all other tested glasses.

Flare and ghosting are extremely well suppressed, quite an remarkable achievement and visibly superior to the Swarovskis and Leica. Images are very "quiet" as a result, and this is a big part of the fun of using this glass - especially great for situations in contrasty woods or deep shadows under bright skies that hunters and birders often encounter. Only the SF might be a little better in this respect. Even with a bright street lantern in the frame the image remains flare free. Against a low sun, performance is lousy though, with a lot of flare, as with all others, too. Here there is much to improve still for all models and makers.

Distortion
This is a classic design, so we have visible pincushion distortion. Panning behaviour is perfect.

Field of view
is 136 meters in 1000 meters distance and feels surprisingly wide and very immersive.

Threedimensionality
of the images is exceptional and the best in any roof prism bino I have seen, although of course not matching a porro prism. The objectives are 6mm wider spaced than the oculars, this is the widest stereo base of all 8x42s on review. The Zeiss SF features 4mm, the Nikon EDG 2mm, the Ultravid 0mm.

Close focus
is extreme with 1.5 meters minimum distance. Performance remains spectacular, there is no trace of softness whatsoever.

Coatings
are high intensity red/tobacco on the oculars, and high intensity purple with some green on the objectives.

Colour reproduction
is neutral to my eyes, with just a tiny hint of green showing up in the studio testing - a real Zeiss heritage which is meant to increase contrast. Images have a natural colour saturation and that lovely, vivid high transmission sparkle that I see in the Ultravid and Habicht 8x30, too. Compared to the Nikon EDG and Leica Ultravid, the HT colours look a little bit less saturated, which I would explain with the brighter image of the HT.

Darkened to midtone, the HT looks neutral with a hint of green.

Brightness
is class leading, Zeiss claims 95%, to my eyes the HT is the brightest glass of the pack. I feel this is even easier to see in good light than in the twilight, so it is something to enjoy constantly, not only in twilight or darkness! Some people complain the HT image looks to bright, what they might mean is that the colours look a bit undersaturated due to the brightness of the image, probably a perceptual phenomenon (to brighten an image decreases perceived colour saturation).

Chromatic aberrations
are not an issue in the center, maybe just a little bit worse than in the SF and Swarovision, but much better controlled than in the Ultravid, and as always they do increase towards the edges.

Eye relief
is 17mm as stated by Zeiss.

Ease of view
is good, but the HT needs, similar to the Nikon EDG and the Leica Ultravid, much more exact placement of the pupils than a Swarovision.

Conclusion

Pros:

1. Best image quality of all models tested, probably due to the combination of superb contrast at all levels and highest transmission.

2. Best sharpness, together with Swarovision and Nikon EDG

3. Best microcontrast at textural level, together with Ultravid

4. Best resolution, together with Ultravid

5. Brightest glass, with lovely high transmission sparkle

6. Excellent, natural, reference colours

7. Most pronounced threedimensionality, half way between a roof and a porro!

8. Superb flare suppression, only marginally bettered by Zeiss SF

Cons:

1. Needs accurate placement of exit pupil/interpupillary distance and adjustment of eyecup length, SF and Swarovision especially are more tolerant in that respect.

2. Ergonomy: Holding the HT close to the front end has a long leverage and does not feel too good for my taste.

3. The HT is very bulky.

Opinion

The HT is an outstanding glass and optically the reference binocular in the 8x42 class. It´s images have a freshness and chrystal clarity the others cannot quite match. The Ultravid has maybe even more beautiful images and handles even better due to compactness, but cannot beat the HT if best and most natural image quality is paramount, especially when it comes to suppression of annoying peripheral flares. Comparing to the SF, I was prefering the HT anytime. The Swarovision is spectacular even at first glance with its extreme sharpness across the whole field and probably overshadowed the HT´s qualities quite a bit, although it lacks the high transmission sparkle, perfect colours and great threedimensionality of the Zeiss.

What could be improved in the next generation of the HT? While the size of the HT should be just right for hunters who often wear thick gloves, it will not appeal to many birders. The Nikon EDG and Leica Ultravid show what is possible at a fraction of the bulk. It would be great to have a compact premium line from Zeiss. And the Ultravid now proves the more compact SP prisms with HT glass can get very close to the bulkier AK prism designs in brightness. Unfortunately, compactness was neither implemented in the SF with its SP prisms.

A look through the HT is always what only the greatest binoculars manage to offer: Not just a view, but an experience, even a revelation. Has the 8x42 HT really gotten the attention it deserves yet? It is probably the best classic 8x42 design and in my opinion and for my taste optically the best of all five 8x42s on review.