Leica Ultravid 8x32 HD Plus review (1 Viewer)

Tobias Mennle said:

Ed,Chosun, Hermann, last posts regarding photographing through objectives and brightness.
...
A 8x32 should have the same light density in the image as an 8x42 at full aperture, otherwise we could not reasonably use them, they would always be much darker than the 8x42s - which is only the case when our pupil size becomes bigger than the exit pupil. Or am I missing something here. I don´t see yet what stopping down to 2.5mm would improve.

Click to expand...

Tobias,

To keep this as simple as possible, your photographs appear to simulate a nighttime comparison when the observer's pupils are open to at least 42/8 = 5.25 mm. Under those conditions the 8x42 Leica transmits 72% more light than the 8x32 model (5.25^2/4^2 = 1.72), which would account for why its camera image is brighter. The comparison is most appropriate for astronomers.

Following the same reasoning, birders operating under daylight conditions typically have 2-3 mm pupils. Hence, in order to simulate such a daytime comparison, it's necessary to stop down the binoculars to a common exit pupil size, e.g., 2.5 mm. I presume this is the same stopped down condition you mentioned with regard to your own daylight observations. Perhaps you'd like to comment on whether Chosun and I are reading this correctly.

Henry has commented often about how to stop down binoculars to make similar comparisons for similar reasons.

Ed

Hi Ed,
5.25 divided by 4 is 31% more
5.25 squared divided by 4 squared is 72% more.
Did not use a calculator so may be a bit out.
I suppose at night 72% more light assuming the eye is not more imperfect at 5.25mm compared to 4mm.

Binastro said:

Hi Ed,
5.25 divided by 4 is 31% more
5.25 squared divided by 4 squared is 72% more.
Did not use a calculator so may be a bit out.
I suppose at night 72% more light assuming the eye is not more imperfect at 5.25mm compared to 4mm.

Click to expand...

:t: Right on, it's an area function, ... and I've corrected it (using my calculator).

Not sure what you mean by the assumption about the eye. Please expand.


Ed

The eye might not be uniform in transmission with a larger pupil size.
Going to extremes a 9mm pupil is unlikely to transmit 4x as much light as a 4.5mm pupil.
This is aside from the imperfections working at f/2 instead of f/4.

P.S.
Going to slumberland soon.

A Happy New Year to all.

I just noticed this thread. I believe Tobias is using the same technique to make his images that I have used in the past. If so, then he is right about exit pupil and aperture having no bearing on the brightness of the images. Just now I quickly made some photos to try to demonstrate this because I think it is easier to show than to explain.

The two on the left were made by pointing the camera into the eyepiece of a 7x50 binocular at full aperture and stopped down to 18mm. Notice that the exit pupils are different sizes, but the light intensity inside each is more or less equal (and would be exactly equal if I had been more careful). If done properly the smaller exit pupil would completely disappear if it were cropped out and placed at the center of the larger one, since after all, it IS the center of the larger one.

The two photos on the right are the same binocular photographed through the front. Now the "aperture" is determined by the field stop of the eyepiece and, for practical purposes, the exit pupil is the size of the binocular objective lens. Once again one of these was made at the full 50mm aperture and the other with the objective stopped down to 18mm. Any small differences you see have to do with haste and sloppiness rather exit pupil size. The card behind the binocular is not perfectly evenly illuminated and the camera was handheld, so not perfectly aligned with the binocular's optical axis.

Henry

Henry, Tobias, (and Ed), I agree that the light intensity will be the same regardless of aperture, but I am also in agreeance with Ed that there is a systematic dimming of the brightness illustrated in the photographs shown correlating with reducing aperture. There is definite truncation of the exit pupil shown in the 8x32 UVHD(+?), and like Ed posted above I am thinking that the differences in brightness photographed are likely due to something along the lines of the camera 'seeing' the image as a fully dilated pupil would, thus making the smaller exit pupil sizes seem dimmer. I don't know exactly the equipment used, and it's modes of processing, or how the manual settings set-up Tobias is using has been affected, but given the systemic nature of the variance shown I would go looking in the metering arena, to see if somehow the dark surrounds of the smaller exit pupils are being integrated in the evaluation.

There are also the effects of truncation and vignetting to consider, and it may indeed be very valid to include these as important consumer information (Note to manufacturers: If you don't want the brightness of your binoculars reduced by these - then design them out! I don't think there is really any excuse for truncated exit pupils .....). In terms of outright brightness, I agree with Ed's suggestion that a masked aperture to represent say a 2.5 -3mm exit pupil should eliminate any of these effects. It would be v - e - r - y interesting to compare the results of the two methods.

Finally, Tobias, I am a bit floored by the notion that the 8x32UVHD+ would not contain any actual HT glass!, although like you, I am thinking it has to be a consideration. Perhaps you could double check this with the factory in general for this 32mm model, and particularly in reference to the unit you tested? :cat:

Just a reference (and acknowledging the vagaries of the internet and specification updating delays /inaccuracies), here is a link to the UVHD+ series that comes up from the main Leica site that comes up by searching from here .... note that the 32mm UVHD model is not listed as a 'Plus' ???
https://uk.leica-camera.com/Sport-Optics/Leica-Birding/Binoculars/Leica-Ultravid-HD-Plus

Curiouser, and curiouser, ....... :cat::cat:


[EDIT]: I just double checked the photos of the physical bins in your x42, and x32 UVHD+ reviews, and the badging on the bins is indicating them as "Plus" model - The difference being the "HD" is in Red which indicates the "Plus" model. Source: http://www.birdwatching.com/optics/2015_titans/review.html


Chosun :gh:

All,

My mistake. I agree to the "exit pupil and aperture having no bearing on the brightness of the [pupil] images." The reason, as Tobias implied, is that as the aperture changes the exit pupil (area) changes proportionately. Assuming uniform photon arrival, therefore, the density per unit area at the exit pupil remains constant. This can be stated mathematically, but it’s overkill.

How does the instrument's brightness, so defined, relate to the observer's perception of brightness? As mentioned earlier, the best approximation to perceived brightness is thought to result from weighting the instrument’s spectral transmission with the standard photopic human visual sensitivity function. I’ve never encountered reports that actually did this, which makes rationalizing anecdotal evaluations such as Tobias' a mystery. No offense intended.

Ed

according to this leica video the 8x32 HD-Plus have HT-glass,
see the attached screen "schott"

https://www.youtube.com/watch?v=uIZqhQt8JYA

Gijs measurements of the HD-plus vs HD will be very interesting to see.
My guess is 2% higher transmission. Perhaps more at 450 nm.

Tobias,
Thank you for the effort, fun though it must have been. This is exactly the way I would compare my 8x 42 and 30mm binoculars, optically. My 42 is a Zeiss FL, closely comparable, I reckon, to the latest thang from Leica. My 30 however is the dramatically different Fujinon FMTR-SX (whose humongous prisms pretty much take field illumination out, although nobody has mentioned it, as a possible suspect in the mysterious perceived brightness effect).

Of course I can't certify the transmissions of these two of mine. Advertising aside, the Zeiss may simply be more transmissive. Your comparison, however, is about as good an "all other things being equal" between 32 an 42 as possible.

I have tested my 42 FL boosted by 7x, and know it to have a little astigmatism in one barrel, which although only limiting the resolution to the very good low 3-arcsec range, is apparently noticeable. I have not tested the Fujinon, but would guess that it doesn't have such an error, cripes, you ought to see this thing. So I'd guess that your, as well as my, sharpness difference may just be a tolerance/defect thing. But although less than perfect optical adjustment doesn't stop Zeiss, it is NOT what Leica is known for...

Individual unit adjustment tolerance/defects can make or break sharpness, but the brightness thing is puzzling. Could there be something here that even we don't understand? Tolerance/defects in coatings? I hope that along with his transmission measurements, Gis will give his subjective impressions of brightness.

Ron

PS. From post #46 above it's clear that Chosun is a clear thinking experimentalist ... and that's a very good thing in my book :t:

Wherever possible one should attempt to eliminate confounding effects, even though they may appear dubious. In this case, masking would also mimic the transmission testing procedure, which sends a uniform narrow beam down the optical center of an instrument regardless of its configuration.

Ed

Fascinating technical discussion, some of which is a bit over my head.

I've just got a pair of 8x32 HDs in a rather fetching green colour. I was vaguely aware that an HD plus is now available, which probably accounts for the fairly good price I paid for my 'regular' HDs. What are the differences between the two? I kind of think I'm not missing out on much compared with the plusses, but maybe I'm wrong?

First impressions are that my new HDs are awesome - the sharpness is incredible. Like my ordinary (pre-HD) Ultravids, the view is 'easier' than with my Victory FLs. Focusing is a big improvement on the old Ultravids, but still not a patch on the silky smooth FLs. The focus is stiffer than that of the FL, but very smooth - the problem is there's a bit of detectable slap/play when operating it. I showed them to Steve in South West Optics in Truro, and he said he'd send them straight back if he received them as stock. I tried two other pairs of the identical model in his shop: one was perfect, but the other displayed the same characteristic as mine.

Should I just acknowledge that no one binocular is perfect, and put up with it? Or do they go back to Leica for adjustment?

First world problems, I know!

Tobias mentioned the 8x32 FLs and how he like to compare them with the Leica - that would be very interesting. Regarding eye relief, I wear spectacles all the time and have never had an issue with the Ultravids, but I appreciate that everyone's particular facial/eyeglass lens characteristics are unique. The eye relief on the FLs is so great, that I actually wind out the eyecups a couple of millimetres to avoid blackouts!

Cheers
John

Again, thanks for all your input. Good to see some sample images from Henry so I am more entitled to feel that stopping down to a 2.5mm pupil will not solve the issues discussed by Ed and Chosun.

About my photographic brightness comparison, I measured the focus distances to the field stop/aperture, they were identical for Zeiss HT, SF and Ultravid 8x42 as well as Zeiss West 8x30 MK2 pro (just below 60cm), but shorter for the Ultravid 8x32, below 40cm, so there should be some light loss due to higher magnification/macro mode. I admit I am not convinced though why the 32s generally should be so much darker.

Ed, comparing binoculars´ brightness with regards to our visual spectral responses can very simply be started with by looking at the colour photographs. It might be another issue to convert them to black and white and then judging brightness.

I plan to further compare the 8x32 and 8x42 Ultravids in brightness by stopping them down to the same 3.5mm pupil size. But there is no way around it, the 8x32 is quite a bit darker even in bright conditions. It is a bit brighter than the Nikon 8x42 EDG though. To be honest, I will not have sleepless nights, the 8x32 is a great package in the field. Today I had a kingfisher 10 meters in front of me and it was sheer beauty...

Generally, flare brightening up the image is now one of my main concerns in comparing brightness. I suspect the 8x42 has higher flare levels than the 8x32, that might be a real issue affecting brightness.

Chosun, these truncated exit pupil may not be nice, but they are certainly not a bit thing, especially as they affect the peripheries only. Compare with the Nikon EDG 8x32, it is way bigger and 90g heavier than the Ultravid, enough space for round pupils, but size and weight could be a real deal breaker for many buyers.

About the HT glass issue, the Leica description clearly says that Plus models feature new coatings AND best lenses AND HT glass prisms, so this is unambiguous. This makes it a bit hard to ask Leica about the truth of this statement. I hope Gijs can shed more light on this when repeating his transmission measurements.

About the Leica PR infos, one quote: "the perfect balance between transmission and contrast ensures rich colours, clear vision and the sharpest detail resolution." In the video linked by vespobuteo, what I tend to call macro contrast (which depends on good flare suppression) is called "dynamic range". Well, contrast (both macro- and micro-) should of course be as high as possible, but I do really believe lower transmission/less brightness makes images look more crisp and colors definitely more saturated. Again, the Nikon EDG 8x42 is a good example for that and the 8x32 Ultravid may well follow the same philosophy.

John, #50, about your Ultravid 8x32, I would definitely have them serviced to get perfect focusing.

Interesting to hear you find them "easier" than the FLs, shows once more how personal and subjective these things are...

I have my eyecups unscrewed for more than a millimeter now and this is the best configuration for me.

Hi Tobias

You're right, I should get them serviced. It's just such a hassle to send them off, but the focuser's bugging me now.

Regarding the HD plus 8x32, what are the differences between them and the regular HDs? Bizarrely, I've seen the new bins advertised at a lower price than the 'old' ones in a UK birding magazine!

Cheers
John

Hermann said:

I've also got one of the old Trinovids, an 8x32 BA dating back to 1993, and I'm still not sure if I really "need" the upgrade. But it is an upgrade, no doubt about it - contrast and transmission are clearly better.

Hermann

Click to expand...

I've got the 8x32 BAs too, but lately I've been finding the image either too small or too dark. I'm wondering if it's time to upgrade and would appreciate others' recommendations.

Some history. I purchased the 10x42 Trinovid Ultras back in the 1980s when Leica first introduced its revolutionary new mechanical design. At the time most of the top birders in my area were using 10x40 Zeiss binoculars. I decided to finally splurge on some alphas, and the Leicas were the most advanced on the market then, so I went with those and was never disappointed.

In the 1990s though, I managed to damage them and decided something lighter would be better so I went with the 8x32 BAs. Ten power had gone out of fashion and I was worried that a 3.2 mm exit pupil would be too small, so I got the 8x rather than the 10x.

Over the years I've begun to miss the old 10x42 image. So I was considering purchasing 10x42s or even 10x50s. With more thought, though, I'm beginning to wonder whether what I really need is more field of view, more brightness and a larger exit pupil rather than more magnification.

So now I'm considering an 8x42 model. I'm tempted by all five of the alpha models. Leica, Zeiss SF, Zeiss HT, Swaro ELs, and Swaro SLC. As I read more, I'm less enamoured of the flat field binoculars, so my choice is rapidly narrowing to the Zeiss HT and the Leica HD Plus. Still debating 8x or 10x too, but leaning toward 8X.

I'd appreciate others' advice. I may not have the opportunity to compare before buying, so advice is very helpful.

The SLC doesn't have field flatteners, but it does have a wide sweetspot.

soloflyfisher said:

I've got the 8x32 BAs too, but lately I've been finding the image either too small or two dark. I'm wondering if it's time to upgrade and would appreciate others' recommendations.

Some history. I purchased the 10x42 Trinovid Ultras back in the 1980s when Leica first introduced its revolutionary new mechanical design. At the time most of the top birders in my area were using 10x40 Zeiss binoculars. I decided to finally splurge on some alphas, and the Leicas were the most advanced on the market then, so I went with those and was never disappointed.

In the 1990s though, I managed to damage them and decided something lighter would be better so I went with the 8x32 BAs. Ten power had gone out of fashion and I was worried that a 3.2 mm exit pupil would be too small, so I got the 8x rather than the 10x.

Over the years I've begun to miss the old 10x42 image. So I was considering purchasing 10x42s or even 10x50s. With more thought, though, I'm beginning to wonder whether what I really need is more field of view, more brightness and a larger exit pupil rather than more magnification.

So now I'm considering an 8x42 model. I'm tempted by all five of the alpha models. Leica, Zeiss SF, Zeiss HT, Swaro ELs, and Swaro SLC. As I read more, I'm less enamoured of the flat field binoculars, so my choice is rapidly narrowing to the Zeiss HT and the Leica HD Plus. Still debating 8x or 10x too, but leaning toward 8X.

I'd appreciate others' advice. I may not have the opportunity to compare before buying, so advice is very helpful.

Click to expand...

If I wanted to avoid flat field bins then I would also short list the two models you have mentioned: HT and Uvid HD+. You won't be disappointed by either of those. But if you are really interested in a bigger field of view I wouldn't rule out the SF. Its flat field is said to be a 'milder' version than Swarovski's and it seems fewer people report rolling ball. Remember that FOV is a disc not a line at 1,000 m so if you calculate the SF's FOV advantage of 8m or 10m as an area it is significantly larger compared with HT and the Leica. SF also has some handling advantages too.

That said, HT and the Leica are both first class.

Good luck with your choice.

Lee

Troubador said:

If I wanted to avoid flat field bins then I would also short list the two models you have mentioned: HT and Uvid HD+. You won't be disappointed by either of those. But if you are really interested in a bigger field of view I wouldn't rule out the SF. Its flat field is said to be a 'milder' version than Swarovski's and it seems fewer people report rolling ball. Remember that FOV is a disc not a line at 1,000 m so if you calculate the SF's FOV advantage of 8m or 10m as an area it is significantly larger compared with HT and the Leica. SF also has some handling advantages too.

That said, HT and the Leica are both first class.

Good luck with your choice.

Lee

Click to expand...

I had trouble holding my 10x42 HT's steady, but if they were 8x42's I would have kept them. The optics are excellent. I can hold my 10x32 UV's steady fairly well, but I ended up getting 8x42's because the 10x32 isnt bright enough for woodland birding. I think an 8x32 UV would be the best all around binocular both because of the optics and ergonomics. Its a small binocular, but its bright enough to use almost anywhere you would use an 8x42.

soloflyfisher said:

..... So now I'm considering an 8x42 model. I'm tempted by all five of the alpha models. Leica, Zeiss SF, Zeiss HT, Swaro ELs, and Swaro SLC. As I read more, I'm less enamoured of the flat field binoculars, so my choice is rapidly narrowing to the Zeiss HT and the Leica HD Plus. Still debating 8x or 10x too, but leaning toward 8X.

I'd appreciate others' advice. I may not have the opportunity to compare before buying, so advice is very helpful.

Click to expand...

Troubador said:

If I wanted to avoid flat field bins then I would also short list the two models you have mentioned: HT and Uvid HD+. You won't be disappointed by either of those. But if you are really interested in a bigger field of view I wouldn't rule out the SF. Its flat field is said to be a 'milder' version than Swarovski's and it seems fewer people report rolling ball. Remember that FOV is a disc not a line at 1,000 m so if you calculate the SF's FOV advantage of 8m or 10m as an area it is significantly larger compared with HT and the Leica. SF also has some handling advantages too.

That said, HT and the Leica are both first class.

Good luck with your choice.

Lee

Click to expand...

Hey Solo,

Try not to be too freaked out by flat-field designs and any propensity they have for exhibiting the 'rolling ball' phenomena when viewing, purely by reading alone. In reality, less than ~20% of people will have a problem, and not all of those would be deal breakers. You really have to view them for yourself to see how they gel with your eyes/brain.

Swarovski has been widely thought to have 'tweaked' their optical distortion formulas in recent years to make them more friendly to more people.

I would also caution that some reports contradict what Lee has said about the SF ...... ie while the field is indeed 'milder' in that it isn't as sharp to the edge, any translation of that into reduced RB effect has turned out to be more marketing than reality with some people bothered by RB in the SF that have no problem with it in the SV ...... It really will be important to eyeball them all yourself.


Chosun :gh:

Good stuff all. Thanks for all the suggestions. Lots to think about. I think I may have to find a store here in the Toronto area where I can get some in hand.