Thread: 8x32 is the new 8x42 binos

I say 'hang up those bulky and heavy 8x42s' and grab yourself a nice compact and light 8x32'.

Why? Well with binos it's about size, weight, image quality, brightness, FOV, and price.
The 8x32 are a better size and weight, the 8x32 field of view is larger than the 8x42, they are usually cheaper than 8x42... BUT the brightness and hence image quality should be better on the 8x42...right?

Well, I've been comparing a mate's 8x42 HD Diamondbacks with a new pair of 8x32 HD binos I've just bought. I had expected to be able to quite easily observe a brighter image with the 8x42, which I thought would become more pronounced as it grew darker. But in reality, I've narrowed it down to only 1 minute of extra light in the 8x42s at dawn or dusk over the 8x32s.
1 minute only...

So why is this? The theory tells us that the 8x42mm should have been quite a bit brighter for longer due to the larger objective lens and hence exit pupil:
8x32 bins produce an exit pupil that is 4mm wide
8x42 bins have an exit pupil that is 5.25mm wide.

Therefore with 8x42s, you have the potential to produce a brighter, better quality view. However, during the day in normal light conditions, a good quality 8x32 binocular is perfectly capable of capturing and transmitting more than enough light to your eyes (as it has a 4mm exit pupil) so that you will observe that bright, high-quality image.

But what about in low light?
Well, the 8x42 does transmit more light through your pupil and onto your retina (5.2mm vs 4mm), so they should be brighter than the 8x32.

However, we are assuming that your pupil is at its maximum diameter of 7mm for those under 25 (smaller size the older you get), which I am not sure it reaches when looking through binoculars at twilight? But even if one's pupil dilates to 5mm, the image produced by the 8x42 model is only brighter to me (and probably to others my age) by 1 minute before dusk or dawn compared to the 8x32.

This difference is so slight that I think having the 32mm objective versus the 42mm is worth it especially for the 250gm weight saving, larger FOV, smaller size, and lower price.

Any opinions?

when comparing apples with oranges you will always get a different flavour.
you say the 32s have wider field of view than the 42s...but they arent the same model.....what do specs of the SAME model say for FOV of the two sizes????

a old nikko stirling gold crown 3x9x40mm will quite simply shit over other 3x9x40mm scopes for field of view.....not 100% sure how but believe its to do with front lens being closer to exit end of scope body...but it is a fact the fov is more...some 2 fence pailings at 30 yards more..... again thats not apples with apples
two leupolds is closer test....but again must be same model and vintage. the 3 different M8 4Xs I had were all different spec...so different in many ways...again not apples with apples.

Both Vortex Diamondbacks.

FOV of 393 feet at 1000 yards, for the Vortex Diamondback HD 8x42
Vortex Diamondback HD 8x32 have a 426 feet field of view at 1000 yds.

I think you will find that the 8×32, has the widest field of view among all types of binoculars on the market.

well they are true to specs then...... all is well..... apples and oranges still apply,let the buyer beware.....read the fine print before handing over your dosh.

It depends. As MD says, "what do specs of the SAME model say for FOV of the two sizes". I prefer an 8x32 to 8x42, 10x32 and 10x42. It's just a good all round size and weight. Currently using Swaro 8x30 CL Companions. Excellent lightweight bino, not quite as good as the Swaro 8x32 EL I once had but not too far behind. I gave up on big, heavy binoculars such as my Swaro 10x42 EL Range some time back.

Have tried 32s before and felt like holding a kids Toy, not enough weight in them, did not like.

Interesting post. I actually wanted Diamondback HD 8x32, but ended up with 8x42 since the latter came with a pouch/harness. Given that binoculars are next to useless for most of my hunting and I use them infrequently, didn't want to spend 25% of the cost of the binoculars on a pouch.

Had a pair of 8x30s for quite a few years and really liked them, especially the superior field of view compared to 10x40s. I changed to 8.5x42 a couple years ago and there was quite a step up in low light performance (admittedly some of this is due to better glass rather than objective size), same FOV (well, 3m less @ 1000m), and the extra 250g in the bino bivvy doesn’t worry me

I think if the weight/bulk of 8x42s is pissing you off, better to drop down to a quality 8x25

I (mainly) use 10x30s as a good compromise of size/weight/performance for all round hunting. Also use 8x25s in the bush.

Got a pair of 8x30 SLCs and trinovid 10x42s.

The heavier 10s dit more stable in the hands and give less eye fatigue when used for long periods.

Just upgraded to ultravids.
My experience may differ from your.
Maybe apples and plums but that’s how it goes in the real world.


Sent from my iPhone using Tapatalk

Originally Posted by Dicko

Got a pair of 8x30 SLCs and trinovid 10x42s.

The heavier 10s dit more stable in the hands and give less eye fatigue when used for long periods.

Just upgraded to ultravids.
My experience may differ from your.
Maybe apples and plums but that’s how it goes in the real world.


Sent from my iPhone using Tapatalk

I had 10x32 ultravids and found them fatiguing when using for long periods too, I found the bigger objective lense much more comfortable to look through whether this is imagined or not its definitely a thing for me.
there's no denying the glass on modern high end binos is fantastic even with smaller objectives I just find them tiring to use for long periods.

I went one step further. I have the 8x32 ultravids and swaro 8x25 cl pockets and always carry the 8x25's.
The time diff is stuff all between them at last light and if it's that dark its time to make tracks for camp.

Originally Posted by Ryan_Songhurst

Have tried 32s before and felt like holding a kids Toy, not enough weight in them, did not like.

Ideal for people with small hands

Yeah right

You are making the classic mistake of just looking at the numbers and trying to convince yourself. Much like guys doing a mini thesis of internet research trying to convince themselves one caliber is superior to another.

For hunting, first and last light is KEY. 42s have a real advantage during that small window. Don't believe me ? Go look through different binos (hopefully of similar optical quality) in real world conditions, and compare actual results. For me the noticeable difference lasted a lot longer than 1 minute.

IMHO, 8x42 is just about the perfect balance between light gathering and fov.

I guess it really depends on what is most important to you:

weight : get a pair of 8x2n mountain binos, or buy chinesium compared to solid euro (always lighter, haha)
light gathering : 8x42, with the best euro glass you can afford