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Leica UVHD+... all I can say is that the view is simply "DELICIOUS" (1 Viewer)


mountain and glacier watcher
United States
I'm not such a big fan of deep depth of field with binoculars - I find it much easier to snap binoculars into sharp focus when the DOF isn't as deep (ex. 10x42 vs. 7x42). And, of course, in photography, shallow DOF has such a great "look", especially when one wishes to isolate the subject razor sharp and render the background in a soft, wonderful, colorful blur. For portrait photographers, especially, very shallow DOF is typically a hallmark of goodness - made possible by the selection of long and fast lenses, and large sensors. And, of course, distance between camera and subject being less than distance between subject and background.
Until recently I would have had little personal opinion on this, but the two things that I really enjoy about shallow depth is the focus that it puts on what you're actually looking at, and the ability to ignore things in the way, like branches for example, which would be far more intrusive if they were in as sharp a focus as the things we happen to be presently viewing. Yes, definitely one of the things I totally enjoyed being able to capture when I was briefly into photography and specialty lenses, razor sharpness coupled with soft, indistinct background/foreground.

Mike F

Well-known member
For me limited DOF (compared to normal vision) is exactly one of reasons why looking through binoculars such a magical experience, and shallower rather than deeper DOF can enhance that experience further.
The same is true of FOV to a large extent for me. I’ve never really understood the desire for the maximum possible FOV, especially at the expense of other qualities. Of course I understand it’s advantages in certain situations - birding, looking for markers when navigating at sea etc, but in general I find (relatively) limited FOV and DOF only help to isolate and concentrate attention on whatever the chosen subject might be.

henry link

Well-known member
From what I learned in photography, optics with identical specifications (magnification and exit pupil) should have the exact same depth of field (DoF), and that largely no other factor affects this, meaning that it is physically impossible for one manufacturer to produce optics with "better" depth of field than those of another (assuming the main general specs are the same).

There are a few caveats though:
1. It's possible that lenses with very high light transmission cause the pupil to shrink slightly, which in turn causes the perceived DoF to increase compared to less bright binoculars (pupil serves as aperture in a photographic lens, and the smaller the pupil, the sharper the image depthwise).
2. The character of the out of-of-focus background ("bokeh") may be different -- some optics may produce out-of-focus backgrounds that look "creamy" (high-quality photographic lenses do this), which causes the viewer to perceive DoF rendering as shallow, while other optics may produce out-of-focus backgrounds that look "busy" (cheaper photographic lenses do this), which causes the viewer to perceive DoF rendering as deep (while in fact in both cases, the DoF is exact same).
3. Optics with a large sweet spot may have different perceived (emphasis on perceived) DoF compared to optics with small sweet spot. For example, I consistently notice that my 10x42 NLs have better apparent DoF than my 8x33 Kowas (roughly similar exit pupil), which is counter-intuitive because normally it is the higher magnification optics that have shallower DoF. I attribute this to larger sweet spot in the NLs which tricks my brain a bit into thinking they have great DoF.
Hi Henry
The obvious question arising from this is: what does the binocular's focus wheel do if it does not bring the image to a focus?
Does it simply focus the image sufficiently that the eye can then finish the job of bringing the image into focus?


Excellent points to bring up, gentlemen. And here I was hoping I could stop thinking about DOF today. :(

I'll start with E_S three caveats.

1. This is certainly theoretically possible, and I've tried to observe it experimentally using up to about a 40-50% change in light transmission, but without much success. I've tried two methods, which I repeated just now.

For both methods I use the same defocused glitter point I described in post # 75. In the first method I simply compared the circles of confusion among a few 8x binoculars with different light transmissions. The highest transmission came from a 8x30 Swaro Habicht at around 95-96% and the lowest was from an uncoated 8x30 Leitz at less than 50%. Others in the group ranged from about 92% to the mid 80s. Unfortunately I've never measured the true magnification of the Leitz, but its circle of confusion did not stand out as especially large among this group which I know to range from 7.8x to 8.2x.

I've used another method that eliminates any differences in optics or magnification. I simply cover a little less than 1/2 of one objective lens of a binocular with black tape, so that it transmits almost 50 percent less light than the other side while still allowing me to see the full diameter of the half moon shaped circle of confusion. Using this method and switching my left eye back and forth between the two sides I just can't see any reliable difference between the sizes of the circles of confusion. My conclusion from this that it must require a bigger change in the amount of light reaching the eye to trigger a change in the pupil dilation of my eye than we normally see from even quite large differences in the light transmission of binoculars.

2. Yesterday when I mentioned differences in aberrations masquerading as differences in DOF this is one example I was thinking of. The desirable soft bokeh behind the point of best focus in a camera lens is achieved by the application of a type of spherical aberration, specifically spherical overcorrection, which causes point sources of light on the far side of focus to form diffraction disks with bright centers that diffuse out to a fuzzy edges. Meanwhile on the other side of focus the diffraction disks appear hollowed out in the center with bright hard rings at the edges, which are not so pretty. Both forms of SA cause a loss of resoluion and contrast at best focus, but in a photo that may go unnoticed because the limit on resolution may come from the sensor rather than the lens.

In binoculars SA is not desirable because of its bad effect on image sharpness, but nearly all of them have it, almost always in the form of undercorrection with puts the nice looking bokeh in front of best focus. How much undercorrection is present affects the appearance of unfocused objects but not how unfocused they actually are and that may lead to the impression that there is more or less DOF in one binocular than other of the same magnification even though there is no difference in the true DOF.

3. If we ignore off-axis astigmatism and just consider a sweet spot limited by field curvature it seems that many people react to a large amount of field curvature is if it's the same thing as wide DOF because the ground plane of focused objects in front of best focus will gradually change to closer and closer objects as you look down toward the bottom of the field. I can also understand E_S opposite impression of objects in the same plane remaining in focus at off axis positions representing better DOF. This is why for purposes of evaluating DOF objects should alway be perfectly centered so that field curvature (and/or off-axis astigmatism) at other positions in the field don't influence the result.


Good catch. I thought about addressing this messy bit yesterday, but I wanted to keep it simple. The binocular focuser could be thought of as an almost infinitely adjustable pair of eyeglasses for correcting the terrible refractive errors imposed on the eye by the magnification of binoculars. It adds positive correction to the eye when moved toward close focus and negative correction when moved toward infinity, all in the interest of keeping the eye's optics happily focused on the retina just as if there were no binocular involved at all.

The only possible small effect of a focuser on DOF I can think of would occur with simple focusers that work by varying the distance between the objective lens and the eyepiece, thereby changing the magnification (and the DOF) slightly for different distances.

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Mike F

Well-known member
Thanks for another fantastic and informative post, @henry link. I enjoy reading the hands on experiences of laymen (with regard to binoculars) like me, but it is the experienced and knowledgeable posts from members like you that make BF the gem of a site that it is. I’m sure your input is greatly appreciated by many! Kiitos!


Well-known member
Hi experts! Just interested, I'm going to offer my Leica UVHD (not plus) 10 x 42 up for sale soon. Optically and bodywise excellent condition, the only declarence would be the focus wheel does not seem as smooth as it should be although it has been serviced by East Coast Binoculars. What sort of price should I expect to get in UK?

Alan Wrightson

New member
United Kingdom
I received a pair of Ultravid HD Plus 10x42 today.

I've enjoyed the Conquest HD 8x32 and 10x42 for many years. They really are excellent, all-around bins! No peer, at their level, I guess.

But recently, I decided to step up and sample some "alphas".

And all I can say is... I won't be needing those wonderful Zeiss Conquest HDs any longer. Fortunately, Conquest HD just HAPPEN to be my wife's favorite bins! They fit her eyeglass wearing needs and she's thrilled with them. She isn't a binocular fanatic, like I am, either. That's all well and good!

My recent Ultravid HD PLUS sampling includes the 8x32, 7x42, and joining today is the 10x42. The UVHD+ 7x42s certainly have impressed me, and the super compact UVHD+ 8x32 are stunningly nice! And so far, I'm even MORE impressed with the UVHD+ 10x42. I think my impressive UVHD+ 7x42's may see a lot less action, now. o_O

In every case, that Leica "look" is stunningly satisfying to me. And while the flat-field sharpness all the way to the bleeding edge offered by some other options isn't undesirable to me, I don't consider that characteristic to be "all that and a bag of chips". Not everyone places high value on flat-field sharpness, all the way out to the edges.

The sweet spot for me - if it covers about 70% from center out, is fabulous. Honestly, I am much less interested in what the very edges look like, than how the sweet spot looks. I DO understand that it is quite a technical accomplishment to get great sharpness all the way out to the edges, but such an accomplishment is not necessarily all that important to everyone who uses binoculars.

I don't scan my binocular view by scrutinizing the image quality at the extreme edges... I move the central area (sweet spot, perhaps 70%?) of whatever bins I am using to MY area of interest. I don't spend my viewing time, staring at the edges.

If something of interest shows up closer to your edge of binocular view, do you keep looking at it, at the edge of your binocular view? Or do you move the binoculars, placing that subject of interest in the center of your binocular view? Yes... the latter, of course!

A wide field of view can be nice to have, as well. But not necessarily nicer to have than a stunning, visually inspiring picture quality "look" presented to your eyes. Perhaps it is the artist/photographer in me that responds to the picture quality that Leica bins present. They are, after all, a premier camera company, renown for stunningly beautiful picture quality.

While some competing options may rate higher on "technical" scoring, or technical "achievement"... Leica still brings that beautifully rich, uber-sharp clarity, pleasingly warm color-character, punchy-color look, contrast, and "sparkle" to the eyes.

In a word... the Leica view is simply visually "DELICIOUS." And, with UVHD+, the clarity and sharpness of detail in the sweet spot is truly stunning! I noticed this right off when I got the UVHD+ 8x32. Then again when I got the UVHD+ 7x42. And today, even MORE so with the UVHD+ 10x42.

In my view, Ultravid HD+ (particularly for those of us who do not wear glasses and don't NEED long ER!) is VERY much in the running, among all the "latest" alphas. The build quality is stellar, they feel great in the hands, the view looks amazing to the eyes... and they are priced SOMEWHAT reasonably, compared to the "latest, greatest" alpha bins. There is a lot to love about ALL of that.

I certainly do enjoy my Zeiss 8x32 SF bins, but they aren't what I most want to reach for. I love the SF ocular balance, the light focus wheel feel, and the wide field-of-view, but as wonderful as the SFs are (and kudos to Zeiss for SF technical achievement!) they come off more "technical" than artistically alluring. The SFs lack the personality and charisma that Leica glass so excels at, and presents to mine eyes. Neither is better than the other, of course, as they are each SO very different from each other.

Bottom line: There are great alpha glass options available to please each and every comer, and every unique preference.

I do enjoy having bins from the BIG THREE (I have two pair of Swaro CL Pockets, also, the 8x25 and 10x25), but the photographer and artist in me is gravitating toward Leica!

One more pair of bins are arriving Friday, to compare to... Zeiss Victory SF T* 10x42. I'm eagerly awaiting this "lauded" pair of bins - I expect they will be quite similar, in quality and attributes, to my pair of 8x32 Victory SF bins.

Yes, I am on quite a roll. :rolleyes: But it's a really fun one.
I totally agree with your comments regarding the Leica view, I own a pair of Leica Noctivids 8 x 42 you would definitely definitely like those as well

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