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fritzthemoose

Vortex Razor 1-6 Exit Pupil?

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Did anyone ever measure it?

They dont list it in the specs at all not even the wrong and useless one like most other companies.

I am shooting right handed with my left eye. So the eyebox is the most important feature for me. Closest to be able to determine the eyebox is the exit pupil.

I am using a Tac30 and was thinking of upgrading. Compared it to a Kahles 1-6 a few weeks ago and also to a Swaro 1-6. Both have a signifacant smaller exit pupil then the Tac30. So no way to go that route. Not going to spend 8 times the money to end up with a smaller eyebox.

Unfortunately Burris lists the wrong and useless exit pupil in the specs but I measured it at around 20mm which would be even better than the TR24 which I have never seen first hand but lists the seemingly correct exit pupil in the specs with 17,5mm

Any info on the real exit pupil of other scopes would be appreciated too.

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I would not worry about it so much. Both the Swaro and the Vortex are excellent optics that are very fast to use and offer a huge field of view. Don't worry about the technical details so much and just shoot. I have shot from a TAC 30 before and its a good entry level scope but I think you will be far happier with the Vortex, Leupold or the Swaro.

Pat

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I am shooting right handed with my left eye.

Picturing this in my head, have you ever considered placing your scope in a 45 degree offset mount on the left side of the upper receiver? I would think right handed/left eye with a rifle would give a very difficult head placement.

You would have to decide how best to zero a scope that wasn't directly in line over a bore, but it might be workable.

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Damn missed that part about right handed left eye. IF you need to shoot with your left eye why not stop fighting nature and shoot left handed as well.

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I was taught that exit pupil equals objective lens diameter divided by power. So a 40mm objective on a 10 power scope has a 4mm exit pupil. In the case of the Vortex, it has a 24mm objective so the exit pupil at max power (6x) would also be 4mm which I was taught was optimum for the human eye. Surely other factors such as parallax based on occular size come in to play, but this is the only rule I've ever known to go by.

Was I taught incorrectly?

You are talking exit pupil and not eye relief, right?

Edited by Mberry

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I am shooting right handed with my left eye.

Picturing this in my head, have you ever considered placing your scope in a 45 degree offset mount on the left side of the upper receiver? I would think right handed/left eye with a rifle would give a very difficult head placement.

You would have to decide how best to zero a scope that wasn't directly in line over a bore, but it might be workable.

I constructed a mount myslef that is left of the barrel but straigt and not tilted. I use it for my so to speak offest reddot. So i have a reddot a little bid left of the barrel and I use it for shooting up to 100m. For everything furhter I use the scope. I had the dot at 10 o clock before but because of the tilt it was a nightmare shooting longer distances with it. So i switched to straight.

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I was taught that exit pupil equals objective lens diameter divided by power. So a 40mm objective on a 10 power scope has a 4mm exit pupil. In the case of the Vortex, it has a 24mm objective so the exit pupil at max power (6x) would also be 4mm which I was taught was optimum for the human eye. Surely other factors such as parallax based on occular size come in to play, but this is the only rule I've ever known to go by.

Was I taught incorrectly?

You are talking exit pupil and not eye relief, right?

that s not true.

what you describe is the entry pupil. I know that most manufacturers use this as exit pupil but its plain wrong. I would also mean that the cheapest china scope for 10 bucks is as good as a 3000 bucks high end scope.

exit pupil differs widely. Swarovski for example lists it for the 1-6 with 9,6mm at 1x mag and not 24 like it would be if we just use what u described. This is like half of what my tac30 has resulting in a far smaller eyebox

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Damn missed that part about right handed left eye. IF you need to shoot with your left eye why not stop fighting nature and shoot left handed as well.

shooting left handed would be fighting nature too a I am dominant right handed :) I was considering this but for several reasons its not an option for me

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Damn missed that part about right handed left eye. IF you need to shoot with your left eye why not stop fighting nature and shoot left handed as well.

shooting left handed would be fighting nature too a I am dominant right handed :) I was considering this but for several reasons its not an option for me

You need one of those helmets the fighter pilots have that lets you see what the rifle sees no matter which way your looking.

Pat

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I was taught that exit pupil equals objective lens diameter divided by power. So a 40mm objective on a 10 power scope has a 4mm exit pupil. In the case of the Vortex, it has a 24mm objective so the exit pupil at max power (6x) would also be 4mm which I was taught was optimum for the human eye. Surely other factors such as parallax based on occular size come in to play, but this is the only rule I've ever known to go by.

Was I taught incorrectly?

You are talking exit pupil and not eye relief, right?

that s not true.

what you describe is the entry pupil. I know that most manufacturers use this as exit pupil but its plain wrong. I would also mean that the cheapest china scope for 10 bucks is as good as a 3000 bucks high end scope.

exit pupil differs widely. Swarovski for example lists it for the 1-6 with 9,6mm at 1x mag and not 24 like it would be if we just use what u described. This is like half of what my tac30 has resulting in a far smaller eyebox

Then what is the formula that makes up exit pupil? I spent a little time searching and everything I've found supports the formula I listed. The only mention of entrance pupil I've found at first glance seems to have more to do with parallax and true center of the image transfer.

Exit pupil, as I understand it, is just the size of the beam of light that is transferred. It has nothing to do with the quality of the image.

Your comparison using the Chinese scope makes no sense. Plenty of other factors go in to scope quality. Exit pupil does not define scope quality. You've got glass quality, tube construction, lens coatings, lens shapes & erector construction to consider (just to name a few things).

I've never really even considered exit pupil as a factor when looking at a scope, other than buying scopes with large enough objective lenses to transfer the light I need at the intended magnification. My 22x scopes only have a 56mm obj, but I know I can turn the scope down to transfer more light to my eye (by increasing the exit pupil) if I need to.

Maybe I'm missing something, you metric guys may have a key that I don't know about. Please, explain what you understand exit pupil to be.

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Damn missed that part about right handed left eye. IF you need to shoot with your left eye why not stop fighting nature and shoot left handed as well.

shooting left handed would be fighting nature too a I am dominant right handed :) I was considering this but for several reasons its not an option for me

You need one of those helmets the fighter pilots have that lets you see what the rifle sees no matter which way your looking.

Pat

no kidding I do know a guy who has one one of those for paintball lol

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I was taught that exit pupil equals objective lens diameter divided by power. So a 40mm objective on a 10 power scope has a 4mm exit pupil. In the case of the Vortex, it has a 24mm objective so the exit pupil at max power (6x) would also be 4mm which I was taught was optimum for the human eye. Surely other factors such as parallax based on occular size come in to play, but this is the only rule I've ever known to go by.

Was I taught incorrectly?

You are talking exit pupil and not eye relief, right?

that s not true.

what you describe is the entry pupil. I know that most manufacturers use this as exit pupil but its plain wrong. I would also mean that the cheapest china scope for 10 bucks is as good as a 3000 bucks high end scope.

exit pupil differs widely. Swarovski for example lists it for the 1-6 with 9,6mm at 1x mag and not 24 like it would be if we just use what u described. This is like half of what my tac30 has resulting in a far smaller eyebox

Then what is the formula that makes up exit pupil? I spent a little time searching and everything I've found supports the formula I listed. The only mention of entrance pupil I've found at first glance seems to have more to do with parallax and true center of the image transfer.

Exit pupil, as I understand it, is just the size of the beam of light that is transferred. It has nothing to do with the quality of the image.

Your comparison using the Chinese scope makes no sense. Plenty of other factors go in to scope quality. Exit pupil does not define scope quality. You've got glass quality, tube construction, lens coatings, lens shapes & erector construction to consider (just to name a few things).

I've never really even considered exit pupil as a factor when looking at a scope, other than buying scopes with large enough objective lenses to transfer the light I need at the intended magnification. My 22x scopes only have a 56mm obj, but I know I can turn the scope down to transfer more light to my eye (by increasing the exit pupil) if I need to.

Maybe I'm missing something, you metric guys may have a key that I don't know about. Please, explain what you understand exit pupil to be.

Take a look on several different lets say 1-4 scopes (some manufactures do list it correclty but most dont) and you will see that the exit pupil differs. If the exit pupil could be calculated like you said, and I also do know what you are referring to then no matter what scope it would always be the same. and it would only determin how big the pupil is when the light enters the scope but not how big it is when it leaves the scope on the eye side.

burris lists it calculated for the tac30 at 24 but i measured it lower.

I dont know the details but something in the scope does effect the real exit pupil.

It seems that the more magnification you have the smaller the exit pupil gets even at 1x. So a 1-4 has at 1x a bigger exit pupil than na 1-6 also at 1x

No exit pupil does not say anything about scope quality but it is the only indication i found about the eyebox. a perfect eye can open up to 7mm or so. so any exit pupil larger than 7mm cannot be used by the eye for light transfer. however, the larger the exit pupil the less sensitive the scope is to proper head placement. and as I am shooting right handed with my left eye I want a scope that is the least sensitive as possible. I am happy to sacrify fov or other things for that if needed

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I dont know the details but something in the scope does effect the real exit pupil.

It seems that the more magnification you have the smaller the exit pupil gets even at 1x. So a 1-4 has at 1x a bigger exit pupil than na 1-6 also at 1x

No exit pupil does not say anything about scope quality but it is the only indication i found about the eyebox. a perfect eye can open up to 7mm or so. so any exit pupil larger than 7mm cannot be used by the eye for light transfer. however, the larger the exit pupil the less sensitive the scope is to proper head placement. and as I am shooting right handed with my left eye I want a scope that is the least sensitive as possible. I am happy to sacrify fov or other things for that if needed

Mberry's formula is correct but the problems that make published exit pupils numbers inconsistent are several.

First is that the claimed power figures are not exact. For instance a 1x4 scope is possibly a 1.3x4.2. Every 1x4 or 1x6 scope I've used (and there have been many) have been more than 1x on the low end. And all 1x6's start off slightly higher on the low end, which helps them achive 6x on the top end.

Second is the construction of the scope itself. A 24mm lens may only be 20mm or 22mm etc once assembled. These are details not always taken into account with published data.

What does this really mean to us in actual use? In my experiance it means nothing. Exit pupil is a value that's a waste of time chasing. Any of the scopes we consider for 3-gun, when mounted and adjusted properly are so close its insignificant. You will run into parallax issues long before the exit pupil becomes a problem. If you have issues lining up your eye with any of the scopes we use its not adjusted properly or it's your technique.

Fritz seems to have a unique problem that I don't think will be fixed by chasing exit pupil numbers. You will need to find a mount and a scope you like, and work it on the range until you build up a proper technique to use it consistently.

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I know it’s an old thread, but some might stumble on it still while searching the web, like I did,  so I’m copy-paste’ing the explanation about exit pupil from https://www.optics-trade.eu/en/showblockcontent/index/?blockid=max_exit_pupil_info (source seams to be Nikon) exit_pupil.JPG

Max. exit pupil diameter

Maximal exit pupil diameter is an important information when you are buying an optical product, that will be in use in the twilight. This information tells us, at what diameter the light comes through the optical product, where it then enters the pupil in the human eyes. 
The exit pupil diameter can be easily calculated from the magnification and objective diameter of the optical product. The objective lens diameter has to be divided by magnification, and then you get the exit pupil diameter. 
For example; an 8x56 binoculars have an exit pupil diameter of 7 millimeters, and 10x42 binoculars have an exit pupil diameter of 4.2 millimeters (56:8=7; 42:10=4,2).
The pupil diameter in the human eye changes in different lighting conditions from 3 to 8 millimeters. On a bright sunny day, the pupil is very small, because of the excess light. In the twilight, the pupil gets bigger so more light can pass through to the retina. 
So if you have a 10x42 binocular, which has a 4.2-millimeter big exit pupil diameter, you won't have as a bright picture like with the 8x56 binocular. This is because the pupil of the human eye will be at its maximum dimension of 8 millimeters, but the light will come through the binoculars only in 4.2 millimeters.

It is a little bit different with variable magnification optical products. There the exit pupil diameter isn't always the same dimension, but it changes simultaneously with the magnification. For example; if we have a rifle scope with a magnification of 3-12 and an objective diameter of 56 millimeters, at maximum magnification we have an exit pupil diameter of 4,7 millimeters. At the smallest magnification on the other side, the exit pupil diameter should be 18.7 millimeters, but because such a big diameter would not have any advantage (because the human eye pupil is maximal 8 millimeters big), the manufacturers install an optical insert which doesn't let the exit pupil diameter grow too big at small magnifications. This is also our maximum exit pupil diameter. If we take the magnification of 7 times, the exit pupil diameter is 8 millimeters, what would be perfect for the brightest picture through this particular rifle scope.

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Thanks, and welcome to the Forums.

 

You're going to be a real nice technical person aboard.    :) 

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On 1/16/2014 at 5:42 AM, Alaskapopo said:

You need one of those helmets the fighter pilots have that lets you see what the rifle sees no matter which way your looking.

Pat

Not joking or being an ass, have you considered using an eye patch? 

 

My wife is cross-eye dominant and <helpfully> passed it along to my daughter. Starting at 6 in archery she used an eye patch and now closes the left (dominant) eye and shoots right handed (for everything, pistol included).

 

I know this isn't the conventional wisdom but it has worked pretty well, much better than my efforts to get a 6yo shooting archery and guns  to use her non-dominant hand.

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