Objective lense size vs minutes gained

[Whitetail74]

Hey everyone, I had a few questions for our glass aficionados here. The Main one is this, I was wondering if anyone could quantify in minutes how much time is gained going up in objective lense size? Obviously going up in exit pupil size by staying the same on magnification will lend to more minutes at low light but how many? For example 10x30 vs 10x42 vs 10x56? Is it 2 minutes? 10? Or perhaps more? I have the same curiosity for spotting scopes as well. I’m not sure if many on here have had examples like this side by side but would be curious for any experiences you all have in this realm.

 

[Fartrell Cluggins]

There are too many other variables at play to answer the question.

 

[BRTreedogs]

Optics 101: Light Transmission Explained!

Regardless of what kind of optic you have -- a spotting scope, a rangefinder, a pair of binoculars, or a rifle scope, there may be subtle tweaks and changes

outdoorempire.com

 

[Whitetail74]

So the article posted only explains exit pupil , objective lense and eye relation ship etc.. I was looking for for an experience quantified into minutes. However I appreciate the input. Additionally I don’t think the variables are too great. What variables would be present if someone took say a certain lineup and tested all of the sizes on a given day? Such as Zeiss conquest where you could use 8x32,8x42 and 8x56 in the same optical lineup? Or slc 42 vs 56 etc..

 

[wyosteve]

I guess I'm a realist, but my thought is: Does it really matter? Just because you can see an animal for a few minutes more or less with a certain glass, where I hunt, it doesn't mean the difference between shooting or not.

 

[Whitetail74]

Good point, I guess I should specify my interest is because I use my glass mostly for whitetail and muleys in the east/Midwest where when on a feeding pattern you can glass right into the night and then make a play the next evening. Or glass them into the evening hours leading up to season. So for me squeezing the very last minute out of my glass would make a difference.

 

[BRTreedogs]

I guess I'm a realist, but my thought is: Does it really matter? Just because you can see an animal for a few minutes more or less with a certain glass, where I hunt, it doesn't mean the difference between shooting or not.

I think it can make a difference in finding/knowing a big buck is in the vicinity they are on out for 15 minutes sometimes.
Can make or brake if you choose to stay in that area or move on.

 

[BRTreedogs]

Good point, I guess I should specify my interest is because I use my glass mostly for whitetail and muleys in the east/Midwest where when on a feeding pattern you can glass right into the night and then make a play the next evening. Or glass them into the evening hours leading up to season. So for me squeezing the very last minute out of my glass would make a difference.

I'm not sure if there is alot of people comparing exact models but different powers and objectives side by side. Other then maybe your buddy sitting over there saying he can still see or not.

Had to do with coatings, glass quality etc.
Not sure if you're gonna get a minutes answer but it does matter

Best I can tell ya is buy the absolute most expensive glass in the lowest power and biggest objectives you are comfortable with.

 

[SomeJackassOnAForum]

Conditions make a difference. Ambient light makes a difference. Are there clouds? Has it snowed? Is the moon out?

That's assuming that the coatings on the binoculars are all equal.

 

[Elkangle]

Lol do minutes matter...heck yes they do !!!


Don't think of it as spotting an animal just before dark and being able to get a shot...but think of it as being more LIKELY to spot an animal in the shadows in the hour before dark... you will never know what you don't see...

Go for the best you can remotely afford...good glass can turn a 14 day hunt into a 5 day hunt...whats that worth ??

 

[*zap*]

you cannot shoot what you cannot see and even if you do not get a shot you get valuable intel.

 

[cbeard64]

Too many variables to quantify as said above. This includes any of a dozen factors. Just know that the better the glass, the bigger the objective, and the lower the power - the longer you will be able to see.

But then:
1)Do you really want to spend $3K on the highest quality glass?;
2)Do you really want to carry a 56mm binocular?
3)Can you see the detail you want to see with a lower power binocular?

See where this is headed?

Everyone wants an easy answer, but there are no one-size-fits-all answer to every question. You have to decide your parameters and try different optics to see what works best for you.

 

[prm]

C’mon folks, it’s a reasonable question. Yes there are variables, but if you compared a Vortex LHT 3-15x42 next to a Vortex LHT 3-15x50, you’d have an idea. Or any number of similar designed binos such as Meopta B1 Plus 8x56, 8x42, and 8x32.
Nightforce SHV 4-14x50, SHV 4-14x56 and even the SHV 3-10x42.
Quite the contrary to “too many variables” I believe it would be rather easy to get a good feel for what the low light benefits of a larger objective would be. Just use two of the same design and you’ve eliminated all the major variables. So, who has two or more of an otherwise similar design optic that can compare?

 

[Whitetail74]

Well stated @prm this is essentially what I’m looking for even just a comparison of two same family optics. El 10x42 vs 10x50 perhaps? Someone on here must have some examples.

 

[83cj-7]

My experience is more with rifle scopes, but the principal applies:
In my opinion, the only way to know is to compare side by side at the same time in the same light and conditions. I have been fortunate enough to work as a firearms instructor at a school and see literally hundreds of optics a year. The most eye opening experience(no pun intended) was a low light rifle class with about 15 guys with good kit. We setup a target at 200 yards and set every riflescope to 12x. All of the students and instructors walked behind the optics and picked the scope that had the best light transmission. We were all shocked by the results. I’m not gonna bash or call any names out openly, but it made everyone Re-think the $ spent on optics, good or bad. The riflescopes in this class were very diverse, ranging from $400 to $4500. Let me just say, most of the time you get what you pay for, but sometimes you get hosed.

 

[deerhunt1988]

My experience is more with rifle scopes, but the principal applies:
In my opinion, the only way to know is to compare side by side at the same time in the same light and conditions. I have been fortunate enough to work as a firearms instructor at a school and see literally hundreds of optics a year. The most eye opening experience(no pun intended) was a low light rifle class with about 15 guys with good kit. We setup a target at 200 yards and set every riflescope to 12x. All of the students and instructors walked behind the optics and picked the scope that had the best light transmission. We were all shocked by the results. I’m not gonna bash or call any names out openly, but it made everyone Re-think the $ spent on optics, good or bad. The riflescopes in this class were very diverse, ranging from $400 to $4500. Let me just say, most of the time you get what you pay for, but sometimes you get hosed.

You can't leave us hanging like that!

 

[83cj-7]

Lol, ummm. I really don’t want to start a big debate on optics or possibly insult someone or there gear. This is another thing I have learned working at the school.
I’m a newbie here, if I could PM, I would discreetly send you the results.

 

[Matt Cashell]

C’mon folks, it’s a reasonable question. Yes there are variables, but if you compared a Vortex LHT 3-15x42 next to a Vortex LHT 3-15x50, you’d have an idea. Or any number of similar designed binos such as Meopta B1 Plus 8x56, 8x42, and 8x32.
Nightforce SHV 4-14x50, SHV 4-14x56 and even the SHV 3-10x42.
Quite the contrary to “too many variables” I believe it would be rather easy to get a good feel for what the low light benefits of a larger objective would be. Just use two of the same design and you’ve eliminated all the major variables. So, who has two or more of an otherwise similar design optic that can compare?

This test would just tell you the effect the larger exit pupil would have for the tester, and likely would change for a new viewer.

Some people see different wavelengths better than others. Some people have eyes that dilate wider than others, which would be extremely important in this scenario.

It isn’t that it wouldn’t be useful information, just that it wouldn’t necessarily translate to another viewer. This would be a good comparison to do for yourself, and would likely tell you what size exit pupil is ideal for your uses.

 

[prm]

But that’s exactly what the question the OP asked; increased viewing time with increased obj size. It might vary a bit person to person, but it likely has bell curve and you could easily start to define that with some simple comparisons of like designs.

 

[Matt Cashell]

But that’s exactly what the question the OP asked; increased viewing time with increased obj size. It might vary a bit person to person, but it likely has bell curve and you could easily start to define that with some simple comparisons of like designs.

It could vary a lot person to person. It could vary a lot between makes/models of scopes.

The apparent brightness with a 7mm exit pupil would be much different for a person who has pupils that dilate to 8mm versus a person that dilates to 4mm.