Biggest Difference between 12x50 vs 12x56

[HullinPhx]

Regardless of brand I understand the FOV but as far as letting light in or distance would you spend the extra and get the 12x56 instead of the 12x50's?

Thanks

 

[cbeard]

I recently read an article by a respected hunting writer that on riflescopes, the human eye's pupil could not accept any more light than could be let in by a 40mm objective up to a 12X setting. In other words any objective larger than 40mm was useless up to 12X (and only marginally useful above that).

I assume this is true with binoculars but am not absolutely positive.I do know there are steadiness problems above 10X and a tripod is most likely needed but you are probably already aware of that...

 

[CDN]

cbeard- Not correcting you, but let me explain this in a different way.#1- the human pupil is approximately 2mm to 8mm in diameter. Typically, the younger you are the pupil dilates and reacts better to low light conditions. In my experience, this is why guys like my Pops are always grabbing for 8x56's instead of the 10x42's-More light coming in into his pupil makes his eyes work less.#2- The optics in question have an exit pupil of 4.6mm for the 12x56(56 divided by 12) and 4.16mm for the 12x50(50 divided by 12). The optics in question don't fit this scenario about light being wasted. They actually are about optimum. There is a point of diminishing return though. Take the 8x56's I spoke of. The exit pupil is an incredible 7mm, just slightly less than the biggest of the human pupils when dilated. This why you don't see bino's that are 10x100, 10mm exit pupil is too much light for the human eye to except. HullinPhx what binos are you looking at? Personal favorite is the Leica 12x50 HD. They are pricey, but well worth it. If cost is an issue the Nikon 12x56 Monarchs are a great piece of glass for the money. Hope this helps. CDN

 

[HullinPhx]

The Bino's in question are the 12x56 Nikon's and the 12x50 Leopaulds. Basically the same price. I have heard that Leo's are not quiet there when it comes to Bino's and their Bread and Butter are single eye glass IE: Spotting scopes and Rifle Scopes.