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Importance of exit pupil diameter for comfort (NL 8x32 vs 8x42) (1 Viewer)


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Good day everyone! My and my wife travel a lot for many years, hike and ski a lot, sail a bit and wanted our own pair binoculars for a long long time. Particularly my wife just loves watching animals - it's one of her greatest pleasures. Recently we started following some birders on instagram and that sealed the deal - I will buy my first (and hopefully last) binoculars primarily for her as a christmas present.

I pretty much settled on the NL 8x32 but ponder NL 8x42 for one reason.

My remaining question is about Exit Pupil Diameter which is 4mm vs 5.3mm on 8x42. I don't care about light that much as I am sure it will be enough for our needs. I am concerned about comfort and ease of use.

In particular my wife is not as patient as I am with fiddly things and is less precise in general. Also she wears glasses (with a slight astigmatism). Her hands shake slightly compared to mine which are rock solid.

I read that larger diameter provides more comfort and is generally easier to use as you don't need to align binoculars that precise with your pupils. This means that hands shake or wind or uneven surface have less effect on viewing comfort. I also don't know if it takes a lot to set them up against your eyes/face properly or do you just lift them up and they are pretty much good (if eye relief is setup beforehand).

I simply worry that she would like to use them in theory but in practice it would be too uncomfortable to use for her for extended periods of time. For example to sit down and watch birds feeding for couple minutes straight, move on and repeat.

What comforts me is that 4mm exit pupil diameter seems to be not that small comparatively. For example people on this forum often consider 10x42 which have 4.2mm or even 12x42 which gives only 3.5mm and they are still happy with their purchase.

Could you please advise? Just share your experiences regarding my list of worries? Is 4mm generally comfortable enough for people? I am unable to try proper binoculars because currently I'm on island, coming back to my country right before christmas which will be too late an so I fish for advise on internet :) Thank you!
I think you will not get any valuable advice in this forum since the beaviour you are describing is highly subjective.
The more exitpupil you have the more forgiving the eye placement will be but if you read a lot of reviews you will find that for some people a particular pair of binoculars works better that another even if the figures imply something else.
Any experience I might give you might be different from your experience when it comes to eye placement and ease of view. This may be due to the facial structur och because of haptiks or other factors. This also means that a pair that works well for you might not work as well for her.
If you are in the market for a binocular in the 2000+ euro price range you and your better half need to try them.

Personally I compared the 10x42 and the 10x32 model and found no difference in the ease of view and eye placement but the size of my hands made the lager model easier to hold. On the other side the smaller one is lighter and more compact. I am ususally on foot when i carry a binocular so I would choose the smaller model based on my needs.
I went from a 10X42 to an 8X32, due to my inevitably advancing age. The extra weight negated the bigger exit pupil for me.

The NL is undoubtedly a superb binocular, so your only decision is which one. Think carefully before you plunk down your money, since it’s likely to be a once only purchase.

Don’t base your purchase on what you read, try very hard to find a place where you can try a demo pair. I have no clue where one buys binoculars in Poland, but I’m sure someone here will know.
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Is 4mm generally comfortable enough for people? Yes!

8x32s are commonly used by birders. Eye placement in 8x42s is generally easier than 32s, but are also heavier, which is an issue for some people. As mentioned in another post bin evaluation is highly subjective.
I hardly see a difference in daily or even low light use: the pupil of a 8x32 is comfortable enough but I'm not 20 anymore.
Because I have glasses, I've noticed that positioning the binoculars in the best position is more important.
For instance, the NL Pure 8x32 and the Zeiss SFL 8x40 comfort is the same.
The NL Pure 8x42 is above but this is because the headrest helps me: same position each time, no pressure on glasses...
Strangely enough, I've never been able to get the headrest to work the same with the 8x32.
What is just as important as exit pupil size is if the eye cup length matches the eye relief of the binoculars, so the cone of light exiting the binocular hits your retina perfectly. So if you get an 8x32 that fits your eye socket depth perfectly they will work very well for you in the daytime in open country, and you will have the benefit of a smaller lighter binocular. The only way to know this is to try the binoculars. In general, though, the bigger exit pupil of an 8x42 will give you more flexibility in matching your eyes to the exit pupil because it is bigger. There are other advantages to a bigger exit pupil binocular also. If your eye dilates enough to use the bigger exit pupil, they will be brighter not only in low light but when looking into the shadows or under the canopy of a forest like Mount Verde in Costa Rica. If you do a lot of birding in low light or in the forest, I recommend at least an 8x42. There are other advantages to the bigger exit pupil also. They tend to have less optical aberrations, can be brighter on the edge of the FOV and show less glare because the glare and aberrations never reach your eyes because they go beyond the field stop of the binocular. That is why many purists carry the big eye binoculars like the Zeiss 8x56 FL, Zeiss 8x54 HT and Swarovski 8x56 SLC even though they are heavier. Henry Link carries a Zeiss 8x56 FL for these reasons, and he had a thread on why the Zeiss 8x56 FL is the best 8x42.
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I recently tried all of the NL's and the 8x42 was the clear winner for me in terms of comfort. If you or your wife wear glasses get the 8x42 it's simply much more comfortable. The 8x32 has slightly less eye relief I found. I had a table full of Swarovski binoculars outside and I tried all the EL's, SLC and the NL's and 8x42 was the only one where when I raised the binoculars to my eyes I didn't have to do anything it was very comfortable and immersive view. I was actually surprised how different the NL's felt in my hands compared to all the others.
I would go for the 8x32. The comfort of lightweight is bigger than the comfort of larger exit pupil. I have the NL 10x32 and the SCL 8x42 and almost always prefer the 10x32. The larger exit pupil of the 8x42 will only count in dim conditions, for me at least. Or your wife has really big hands. Than maybe the 42 would suite better. I think she would really appreciate lightweight. NL pure 42 is not really light.
Its good there is such a clear consensus. πŸ˜€
Amazon generally allows something like 30 days to return and there usually is no postage to pay. Buy both. Keep the best fit.
I’ve bought both. For me the 42mm is the clear winner in Comfort from EP, but also in picture quality. Is much more immersive. For me the 42 is a complete different animal. So I have sold the 32mm.
A very good compromise for a leight weight 42mm top Bino is the SF 8x42. This is my 42mm carry allaround Bino. The 780gramm ant the Ergo Balqnce concept is amazing. Also the Viewing comfort is for me perfect at this Bino.
The best all around Bino I think!
Hi @hyperscientist. As one member pointed out already, you will not find an exact answer from this forum. Because, face shapes, birding habits, habitats, and personal preferences vary among group members. As a few are already mentioned, since you are buying a very expensive pair of binoculars, the best way is to try different pairs with your wife if possible, rather than trying to impress her on her birthday. Trying a few different binoculars from different brands is even better because it seems this is going to be your first binoculars and you do not have much experience with binoculars. I think you shouldn't restrict your choices for NL. For instance, some people like flat-field binoculars such as NL, and others prefer optics with some field curvature. Flat-field binoculars can make some people sick πŸ˜€ So I thought to give an example from myself hoping it will be useful to you.

I also wanted to buy one of the best pairs of binoculars for birding. I read many reviews and finally decided on buying an NL pure. I bought an NL 8x42 after comparing it with a few other binoculars namely, NL 10x42, El 8.5x42, Noctivid 10x42, and Ultravid 10x42. Initially, I was looking for 10x42 binoculars but I chose NL 8x42 purely due to optical performance. Before that purchase, I had experience with a few other less expensive models. However, lately, I realized that I used NL 8x42 only a few times after the purchase especially due to the size and weight that doesn't suit my birding habits. Recently, I bought a used pair of Ultravid HD 10x32 which has a small exit pupil compared to the NL 8x42 and found out it impressed me more than NL with its' easier eye placement and immersive view. It has comparatively less eye relief that most people criticize but I found it to be perfect for me to have an immersive view (I am not wearing spectacles). Even though the optics of NL 8x42 is superior, the usability of it for me is rather less due to the less stability influenced by the weight. So, I can have a better optical experience with even smaller binocular formats including 8x20 due to the less weight that makes the view stable. As you are hiking more often the better option could be the 8x32. SFL 8x40 could be another consideration due to its' less weight and the larger exit pupil. I wish you all the best to find out the best binocular that suits you and your wife πŸ™‚πŸ™‚
Also she wears glasses (with a slight astigmatism).

first of all welcome to the birdforum... :)

With the NL it can also be decisive whether your wife is short or far-sighted, I have found that the distance between the eyes and the eyepiece is suboptimal for far-sighted people.

Many people, many opinions, I prefer binoculars from an EP. of 5mm. or more, glasses wearers in particular often benefit from a larger EP. but the best way is to try binoculars yourself, what suits one person may not suit another, binoculars are and remain very subjective.

Could you please advise? Just share your experiences regarding my list of worries? Is 4mm generally comfortable enough for people? I am unable to try proper binoculars because currently I'm on island, coming back to my country right before christmas which will be too late an so I fish for advise on internet :) Thank you!

Comfort wise, a 4 mm EP will be enough in daylight, as the pupil size for most people is smaller in those conditions.
My experience is that things starts to get a bit more fiddly at 3mm and less (in daylight).

In low light, a larger exit pupil (5mm or larger) will be more suitable,
and I guess that's why the "average bin" is 8x42, as you have some margin there.
I find Binoculars with exit pupils smaller than about 5mm uncomfortable to look through for more than a few minutes. For this reason, I seldom use my 8x32 EL unless I plan to do a lot more carrying than looking.

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