Print Page | Close Window

8x vs 10x (I know, I know)

Printed From: OpticsTalk by SWFA, Inc.
Category: Other Optics
Forum Name: Binoculars
Forum Description: Anything that requires two eyes to look through it
URL: http://www.opticstalk.com/forum_posts.asp?TID=43774
Printed Date: October/23/2017 at 19:31


Topic: 8x vs 10x (I know, I know)
Posted By: wesgar
Subject: 8x vs 10x (I know, I know)
Date Posted: December/22/2016 at 08:42
I know, it's been asked and answered again and again, but please allow me to clarify. For the sole purpose of judging antlers in poor light, all else being equal (same model from same mfg with same obj. size), does the added magnification of a 10x outweigh the smaller exit pupil of the 10x bino. I realize that the 8x may have some advantages with regards to scanning for game, e.g. wider field of view, less apparent shake, less weight, etc., the question pertains solely to the ability to resolve antlers in failing light.

I have only ever used an 8x bino, a Pentax SP 8 x 43. I love the bino in good light and for finding game, but lose the ability to resolve antlers when the good ones typically come out. I plan to upgrade to better glass and would like some input on the better choice. If it matters, the main contender at this point is a Swaro SLC in 8x42 or 10x42. I of course realize the benefits of a larger objective lens for low light viewing, but I have to carry these things around, so I don't plan to go larger than 42 mm. Thanks.



Replies:
Posted By: Steelbenz
Date Posted: December/22/2016 at 09:05
Okay I'll let you answer your own question! Can you count the horn on the deer with the naked eye from 10 yards away but not 12.5 yards away? Because that's the difference!

-------------
"Don't argue with a fool! From a distance you can't really tell who's who!"


Posted By: Rancid Coolaid
Date Posted: December/22/2016 at 09:15
With same glass and same objective size, lower power will be brighter.  If this is genuinely a failing light question, the 8X will get you a minute or 2 more usable light time.  

But, seeing well enough to identify with an 8X bino is very different from seeing well enough to take a shot in that same light.


-------------
The plural of "anecdote" is not "data."


Posted By: Steelbenz
Date Posted: December/22/2016 at 09:25

RC is correct that your going to get 1mm more light through the 8x and with a 42mm objective lens it should be a significant difference. 25% more useable light!

10x  = 4.2mm

8x = 5.25mm

5.25 - 4.2 = 1.05

1.05 / 4.2 = .25

ergo 25% more light and still below maximum usable. Make me think about helps both of us! I stand corrected!



-------------
"Don't argue with a fool! From a distance you can't really tell who's who!"


Posted By: jonoMT
Date Posted: December/22/2016 at 11:30
I've had 3-15X scopes with the best glass possible that would out-resolve a cheap spotting scope on 30X. I'd bet on an 8X upgrade over going to 10.

-------------
Reaction time is a factor...


Posted By: JGRaider
Date Posted: December/22/2016 at 12:09
The fact is, given the same binocular in 8x42 vs 10x42, the 10x will out resolve the 8x every time, allowing you to see more detail.  


Posted By: Bitterroot Bulls
Date Posted: December/22/2016 at 12:13
Originally posted by JGRaider JGRaider wrote:

The fact is, given the same binocular in 8x42 vs 10x42, the 10x will out resolve the 8x every time, allowing you to see more detail.  

This is true, and the benefit is greater at greater distances ... until atmospheric disturbance (conditions dependant) interfere.  Then the lower magnification has a small advantage, IME.

As a western hunter, under most conditions, I prefer 10x (especially tripod-mounted).  However, I am content with 8x as well (I like 8X32 for 8x bins).


-------------
-Matt


Posted By: WJC
Date Posted: December/22/2016 at 13:21
Almost all of the answers on binocular forums deal exclusively with the mechanical side of optics. And, considering that, you have been given some reasonable answers. However, there is a physiological side of the matter that is—considered or not—quite weighty. Not only does visual acuity change from person to person, it changes for the SAME person due to a constantly changing set of conditions.

A few years ago, Steiner ran an ad showing a hunter on one knee looking through his Steiner binocular. The headline read "When every second counts." Yet, when EVERY SECOND COUNTS, playing with your binocular is tremendously foolish.

In the 8x Vs. 10x comparison, you will find many people who can make a concrete case for either. If it's a high-quality instrument, either will make you happy. Don't over think the matter. You will see more clearly looking through either binocular than you will looking through the debate.

'just Sayin'


-------------
"However elegant the strategy, you should occasionally look at the results.—Winston Churchill


Posted By: mike650
Date Posted: December/22/2016 at 13:24
Another western hunter here, if given the choice I'll take 10x every time.


That's what makes me happy.  Wink


-------------
Fish to Live, Live to Hunt


Posted By: supertool73
Date Posted: December/22/2016 at 13:34
I like 10x as well.  But I do love the compact size of my 8x32s. 


-------------
Lifetime warranty and excellent customer service don't mean a thing when your gun fails during a zombie attack.

"A Liberal is a person who will give away everything they don't own."


Posted By: 3_tens
Date Posted: December/22/2016 at 13:58
Originally posted by JGRaider JGRaider wrote:

The fact is, given the same binocular in 8x42 vs 10x42, the 10x will out resolve the 8x every time, allowing you to see more detail.  
This statement could be misleading. I learned about clarity while on an Antelope hunt in SD. Looking at some large whitetails with my 10x50 Nikon binocular. The Nikon failed to allow me identify the rack on the whitetails. Where the tiny 7x20 lens in my Leica rangefinder the racks were clear and countable. Glass quality trumps everything else.


-------------
Folks ain't got a sense of humor no more. They don't laugh they just get sore.

Need to follow the rules. Just hard to determine which set of rules to follow
Now the rules have changed again.


Posted By: JGRaider
Date Posted: December/22/2016 at 14:07
Originally posted by 3_tens 3_tens wrote:

Originally posted by JGRaider JGRaider wrote:

The fact is, given the same binocular in 8x42 vs 10x42, the 10x will out resolve the 8x every time, allowing you to see more detail.  
This statement could be misleading. I learned about clarity while on an Antelope hunt in SD. Looking at some large whitetails with my 10x50 Nikon binocular. The Nikon failed to allow me identify the rack on the whitetails. Where the tiny 7x20 lens in my Leica rangefinder the racks were clear and countable. Glass quality trumps everything else.


It's not misleading at all.   I specifically said "same binocular", as in same make and model.   You compared Nikon with Leica, not at all what I said.    


Posted By: 3_tens
Date Posted: December/22/2016 at 15:31
I said " could be" because many of today's genera that can't digest a multi faceted thought. They will only read that 10x will out resolve the 8x every time. So often things are taken out of context.  The 2x magnification increase will degrade the image quality using the identical same objective lens. Your eye may not see the difference. I know my eye couldn't. Your using "This is a fact" disqualifies your statement. Mathematically it is not a fact. Not even to bring in the 2x magnification of hand shake knowing binoculars are mostly hand held for use.


-------------
Folks ain't got a sense of humor no more. They don't laugh they just get sore.

Need to follow the rules. Just hard to determine which set of rules to follow
Now the rules have changed again.


Posted By: JGRaider
Date Posted: December/22/2016 at 18:30
Forget the math.  I've done it hundreds of times in the field.  That's good  enough  for me.  


Posted By: WJC
Date Posted: December/22/2016 at 18:44
"Good enough for me" takes us back to the personal physiological aspects of the matter, which rarely enter into it. We all have differing degrees in our thresholds of recognition (clinically: sensory thresholds). Thus, when getting that close to an answer, one is splitting ever-changing hairs with an ax.




-------------
"However elegant the strategy, you should occasionally look at the results.—Winston Churchill


Posted By: Rancid Coolaid
Date Posted: December/22/2016 at 20:27
Originally posted by JGRaider JGRaider wrote:

Forget the math.  I've done it hundreds of times in the field.  That's good  enough  for me.  


Forget the math... the earth is flat, I've seen it!

Knowing something absolves from the knower any need to think.

So awesome.

As said before. 8X will be brighter, all other factors being equal. Increased light will give you a few more minutes. When glass, make, model vary, lots of things influence.

"Forget the math", so awesome!

-------------
The plural of "anecdote" is not "data."


Posted By: JGRaider
Date Posted: December/22/2016 at 20:49
Thank you sir, glad I could help you out.  


Posted By: mike650
Date Posted: December/22/2016 at 20:53
I have 7x42 SLC's that are excellent in low light, very sharp, zero eye strain, etc. etc. but I still fall back to my 10x42 EL's when hunting.   Loco    Bandito


-------------
Fish to Live, Live to Hunt


Posted By: James@SWFA
Date Posted: December/23/2016 at 11:31
I personally have a pair of Zeiss 8x42 conquest hd's ( http://swfa.com/optics/browse/zeiss-8x42-conquest-hd-binocular.html - http://swfa.com/optics/browse/zeiss-8x42-conquest-hd-binocular.html ) and like them a lot.  Most of my hunting is done with a lot of brush in the background and low light can get pretty tough sometimes.  I've been able to more easily spot game and haven't had many problems counting their horns on the 8x vs 10x powers.  I am not as versed on all of the technical jargon or ins and outs with binos, however, I get a chance to look through a lot of them up here and for the money I went with these.


Posted By: koshkin
Date Posted: December/23/2016 at 12:55
A couple of comments: to present the same quality of the image, a 10x42 binocular needs to be a bit better than the 8x42.  That sorta come with higher magnification: alignment tolerances are tighter, etc.

Assuming the overall image quality between an 8x and 10x are comparable, and especially if low light is in play, I would suggest you consider a 10x50 instead of the 10x42.  Also, there is technique involved, so if you want to use a higher magnification binocular handheld, a little experimentation and careful consideration of fit are important.

10x50 is usually a little heavier and longer which helps keep it steady.  The lighter the binocular, the more hand tremor you will see.  Same for the length. Longer is typically steadier.

Increased exit pupil also helps.

When I have to use a binocular handheld, I try to anchor the eyecups on my eye socket bones.  That really helps me keep them steady.  However, how well I can do that really depends on the size and shape of the eyecups, so I am a bit picky in that regard.

Going above 10x handheld is difficult for me (although with any sort of support things change) for any sort of extended glassing.  If all I am looking for is a quick glance, I have learned to stabilize myself reasonably well (mostly because I have been testing SWFA's new 12x32 binocular and had to figure it out).

ILya
 


-------------
http://www.opticsthoughts.com - www.opticsthoughts.com
http://www.opticsthoughts.com - opticsthoughts.smugmug.com
Those who are merciful to the cruel, are cruel to the merciful.


Posted By: supertool73
Date Posted: December/23/2016 at 14:44
For steadying I like to have on a ball cap and I put two of my fingers on each side up over the bill of my cap.  When doing that I have almost no shake.  I can even hold 12x50s pretty steady that way. 


-------------
Lifetime warranty and excellent customer service don't mean a thing when your gun fails during a zombie attack.

"A Liberal is a person who will give away everything they don't own."


Posted By: PhilR.
Date Posted: December/23/2016 at 20:21

OP - you might research the term "twilight factor".  If you do so, you will find that JGRaider is correct.  Exit pupil is not the only thing that determines how much detail you can see.  And yes, I have tried the same exact scenario you describe, and I can tell you that you will be better off with a 10x.

And if brightness becomes an issue, you could always go with a 10x50, and be where you would have been with an 8x42.  Actually, IMO any hunter that is worried about 10x brightness should be going with a 50mm anyway.......



Posted By: koshkin
Date Posted: December/23/2016 at 21:22
Originally posted by PhilR. PhilR. wrote:

OP - you might research the term "twilight factor".  If you do so, you will find that JGRaider is correct.  Exit pupil is not the only thing that determines how much detail you can see.  And yes, I have tried the same exact scenario you describe, and I can tell you that you will be better off with a 10x.

And if brightness becomes an issue, you could always go with a 10x50, and be where you would have been with an 8x42.  Actually, IMO any hunter that is worried about 10x brightness should be going with a 50mm anyway.......


Twilight factor in this case is only applicable if you eye pupils do not dilate beyond 4mm or so.  If they do, you can throw the whole twilight factor business out.

ILya


-------------
http://www.opticsthoughts.com - www.opticsthoughts.com
http://www.opticsthoughts.com - opticsthoughts.smugmug.com
Those who are merciful to the cruel, are cruel to the merciful.


Posted By: oldfortyfive
Date Posted: December/23/2016 at 22:28
Originally posted by supertool73 supertool73 wrote:

For steadying I like to have on a ball cap and I put two of my fingers on each side up over the bill of my cap.  When doing that I have almost no shake.  I can even hold 12x50s pretty steady that way. 

I've been doing that for years also. It works great.


Posted By: wesgar
Date Posted: December/24/2016 at 06:52
Thank you all for your responses.


Posted By: Bird Watcher
Date Posted: December/24/2016 at 12:49
"I learned about clarity while on an Antelope hunt in SD.
Looking at some large whitetails with my 10x50 Nikon binocular.
The Nikon failed to allow me identify the rack on the whitetails.
Where the tiny 7x20 lens in my Leica rangefinder the racks were clear and countable.
Glass quality trumps everything else."


Clean glass also has its virtues. Perhaps the Nikon lenses just needed to be cleaned up. :lol: 





-------------
I prefer Porro prism binoculars especially those made in Japan. (i.e. Minox BD 10x44 BP) 8>)


Posted By: Bird Watcher
Date Posted: December/24/2016 at 13:06
Originally posted by koshkin koshkin wrote:

Originally posted by PhilR. PhilR. wrote:

OP - you might research the term "twilight factor".  If you do so, you will find that JGRaider is correct.  Exit pupil is not the only thing that determines how much detail you can see.  And yes, I have tried the same exact scenario you describe, and I can tell you that you will be better off with a 10x.

And if brightness becomes an issue, you could always go with a 10x50, and be where you would have been with an 8x42.  Actually, IMO any hunter that is worried about 10x brightness should be going with a 50mm anyway.......


Twilight factor in this case is only applicable if you eye pupils do not dilate beyond 4mm or so.  If they do, you can throw the whole twilight factor business out.

ILya


Here's some quotes, from "How to Choose Binoculars", by Alan R. Hale, 1991, regarding Twilight Factor:

This formula (T.F.) takes magnification more into account than the Relative Brightness Index (R.B.I.)
and is a better indicator of brightness.
It has been proven that when observing low contrast subject matter during twilight (not in the dark) higher magnifications will increase contrast and more detail will be seen.

The bold lettering was in his book.

Stan



-------------
I prefer Porro prism binoculars especially those made in Japan. (i.e. Minox BD 10x44 BP) 8>)



Print Page | Close Window