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    Posted: January/21/2009 at 23:10
I want to buy new scope for my 30 06. I will be hunting early in the morning and sometimes even late at night. I'm deciding between Nikon monarch 2-8*32 or 2.5-10*50. I prefer 2-8 32 because of its size and wider FOV but my concern is performance in low light conditions. My understanding is that the only time the 50mm comes into question is in low light situations where you are using a 6x magnification or better.Since middle aged persons have pupils that can dilate from anywhere from 4 to 6mm, and any exit pupil over that won't give you more useable light, does this mean that at 5*both scopes will perform same in low light conditions. (At 5* they both have exit pupil > than 7mm. ). At 5* is the 50 mm more clear or they are same? Thank you 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ed Connelly Quote  Post ReplyReply Direct Link To This Post Posted: January/21/2009 at 23:44
Well, 7mm would be the optimum exit pupil that the human eye could actually make use of. So, if you divided 7 into the 32mm scope you would have a 7mm exit pupil at 4.5X.  If you increased your power past 4.5X you would begin to lose your 7mm exit pupil.
 
With the 50mm scope you could turn your power up to 7.1 and still have an exit pupil of 7mm.  So you would gain the ability to crank up your power and still have Brightness.  But the scope has got to be a quality scope....and the Nikon is a good scope. 
 
So it all depends on what you want.  Do you want a heavier scope that you will need to mount higher in order to gain a little brightness at higher powers? 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Urimaginaryfrnd Quote  Post ReplyReply Direct Link To This Post Posted: January/22/2009 at 00:02
You are on track 5power times 7mm exit eye pupil=====> gives you 35 mm objective anything over 35mm is wasted space.   As age increases your eyes may no longer dialate to 7mm so lets say you are still doing pretty good and 6mm times 5power =====> gives you 30mm objective anything over 30mm is wasted space.   However take that 50mm and divide by 7mm exit eye pupil and it will be bright at =====> 7.14 power max brightness
or say you only can use 6mm ======>  8.3 power max brightness.
Here is the kicker though --- even though you can see really well through the scope the selection of reticle becomes very important in low light and the best choice is an illuminated reticle.  While I understand that you are trying to stay in a reasonable price range I will recommend a couple of scopes that I believe would serve you well.
TR20 Trijicon 3-9x40 Accu-Point Rifle Scope                                                                                  Trijicon 3-9x40 Accu-Point Rifle Scope
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TR21 Trijicon 1.25-4x24 Accu-Point Rifle Scope                                                                               Trijicon 1.25-4x24 Accu-Point Rifle Scope
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 Suggest you watch the Trijicon video 

11419 Aimpoint 9000L 30mm Red Dot Sight                                                                                       Aimpoint 9000L 30mm Red Dot Sight
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403280 IOR 4x32 Hunting Rifle Scope                                                                                            IOR 4x32 Hunting Rifle Scope
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SWFA: $359.95

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Post Options Post Options   Thanks (0) Thanks(0)   Quote new hunter Quote  Post ReplyReply Direct Link To This Post Posted: January/22/2009 at 12:31
Thank you guys !!! I'll go with 2-8 32mm. Your help is appreciated. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote seawolf Quote  Post ReplyReply Direct Link To This Post Posted: January/23/2009 at 04:44
This is the strangest selection on low light scopes I have ever seen Whacko
Not one of them are pr. definition "low light scopes".
 
A scope for use at low light ( like stretching the dusk and dawn a little bit, or hunting  moon lit fields a night like we do in Europe), starts at 50mm. 
You can keep on figuring exit pupils til hell freeze over, but when the front lense diameter goes less than 50 mm, you are playing in a sub division.
 
A reasonable starter is the Zeiss Conquest 3,5-10x50 with #4 reticle.
It combines low weight, ok glass quality, ok price and still one have reasonable field of view on the lowest setting.
Same goes for the VXIII 3,5-10x50 with the HD reticle
A red dot helps, but must be sharp in defination and not some fluffy red spot floating out there.
Top quality glass will always give you an edge but cost more.
 
Just my two cents Gentlemen Wink
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Post Options Post Options   Thanks (0) Thanks(0)   Quote hunter12345 Quote  Post ReplyReply Direct Link To This Post Posted: January/28/2009 at 15:32
Buy a 3-12 x56 Docter for low light hunting.Cost around $900.00 USD.This scope brings in light after legal hunting hours here in NY so it should be worth the cost. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote RifleDude Quote  Post ReplyReply Direct Link To This Post Posted: January/28/2009 at 15:52
Originally posted by seawolf seawolf wrote:

This is the strangest selection on low light scopes I have ever seen Whacko
Not one of them are pr. definition "low light scopes".
 
A scope for use at low light ( like stretching the dusk and dawn a little bit, or hunting  moon lit fields a night like we do in Europe), starts at 50mm. 
You can keep on figuring exit pupils til hell freeze over, but when the front lense diameter goes less than 50 mm, you are playing in a sub division.
 
A reasonable starter is the Zeiss Conquest 3,5-10x50 with #4 reticle.
It combines low weight, ok glass quality, ok price and still one have reasonable field of view on the lowest setting.
Same goes for the VXIII 3,5-10x50 with the HD reticle
A red dot helps, but must be sharp in defination and not some fluffy red spot floating out there.
Top quality glass will always give you an edge but cost more.
 
Just my two cents Gentlemen Wink
 
I agree with you if you're talking about a variable with 10X on the high end and you routinely use more than 7X magnification during low light and night hunting.  All else being equal, a 50mm and larger objective DOES NOT provide a benefit in usable light transmission until you get to 7X and greater magnification.  Although in an absolute sense, a larger objective always transmits more light, depending on the magnification, the human eye wont be able to use the additional light and the image won't appear brighter once the optic's exit pupil exceeds about 6 - 7mm because your iris is the limiting aperture.  On a low powered variable, a 50mm and larger objective is absolutely useless.  At 6X and below, for instance, a 42mm objective provides all the light your eye can use, which is why you don't see 50mm objectives on low powered scopes.  This all assumes we're talking about good optics in the first place, with coatings optimized for light transmission in the blue spectrum.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote seawolf Quote  Post ReplyReply Direct Link To This Post Posted: January/28/2009 at 18:34
Rifle Dude.
I´m 63 years old, and my eyes have more or less the same age Wink
That means I do not have the same good eye sight as a young man.
 
For me the figuring of exit pupils and all the other numbers means less and less.
Practical use (and I do a lot of low light hunting) tells me that a low light scope starts at 50 mm.
I´m sure that some can do with a scope with a lesser objective, but as I said, then you are playing in a sub division regarding low light perfomance.
 
I use the lower settings to identify the deer, then crank up to 8 or 10 for the shot.
This work wonders at least for me.
I also find that + 8 magnifying gives me a much better and clearer sight picture, even if the tables says that my old eyes should not take any benefit from such.
 
Two of my rifles  have  50 mm objectives, the third have 56 mm and the one I use for  daylight hunting have 42 mm.
( I must also admit that my Ruger Hawkeye  in 375 Ruger have an old Vari X III 2,5-8x36 with #4 reticle which is perfect for this rifle and the way I use it, moose and Africa Big Smile )
 
Some might call this big scopes drain pipes, but my experience is that I gain a hell lot of "sightfullness" , (is there such a word ?? Whatever ) using these scopes compared with 32, 36, 40 and 42 mm scopes (we are still talking low light hunting).
 
The bottom line is that using scopes that are suited for the spesific task, have got me truck loads of venison in the freezer.
Small objectives scopes would have seen me home empty handed.
That´s  what counts for me.
 
By the way...this is my dusk and dawn rig.
Ruger No1, 270 Win. Scope is Zeiss Victory Diavari 3-12x56 with reticle #40 red dot.
Scope rails are changed to Brownells two piece and the rings are Warne.
This rig would never got a medal in a beauty contest, but is a stable, heavy, accurate and deadly combo for this spesific kind of hunting.
 
 
This is Ugly Betty, A Ruger M77 in 35 Whelen with a Vari X III 3,5-10x50.
This is my "go to rifle" that takes care of everything from magpies to moose.
And no one shall tell me that this combo is ungainly, heavy, to big or to small.
10 yars of steady use have told me that it simply WORKS!
 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Kickboxer Quote  Post ReplyReply Direct Link To This Post Posted: January/28/2009 at 18:46

VERY NICE rigs... I like them.  The #1 looks outstanding to me.  
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tahqua Quote  Post ReplyReply Direct Link To This Post Posted: January/28/2009 at 19:08
Very nice, seawolf. I like both of them.
Did you do the camo work on the 77?


Edited by tahqua - January/28/2009 at 19:09
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Gunshow75 Quote  Post ReplyReply Direct Link To This Post Posted: January/29/2009 at 07:55
Originally posted by RifleDude RifleDude wrote:

...All else being equal, a 50mm and larger objective DOES NOT provide a benefit in usable light transmission until you get to 7X and greater magnification.  Although in an absolute sense, a larger objective always transmits more light, depending on the magnification, the human eye wont be able to use the additional light and the image won't appear brighter once the optic's exit pupil exceeds about 6 - 7mm because your iris is the limiting aperture.  On a low powered variable, a 50mm and larger objective is absolutely useless.  At 6X and below, for instance, a 42mm objective provides all the light your eye can use, which is why you don't see 50mm objectives on low powered scopes.  This all assumes we're talking about good optics in the first place, with coatings optimized for light transmission in the blue spectrum.

As compared to smaller objectives, the added light energy collected by larger lenses is distributed throughout the entire image, from the center to the outer edges. Thus, as you say, bigger is better.

The human eye can handle a contrast ratio (ratio of light to dark) of about 10,000:1 under normal viewing conditions. Dark adaptation can increase this to 1,000,000:1.

In a discussion about low light levels, the diameter of our pupil is only one of the mechanisms used to regulate the amount of light we can use. If we assume the diameter of our pupils range from 2mm to 7mm, that difference can only change the light level coming into our eye by a factor of about 12. The remainder of the sensitivity difference is controlled by chemical changes.

As regards large objectives for low magnifications, I am pretty sure that Swarovski has introduced, or will soon introduce, a Z6, or Z6i, 2-12x,56 scope.


Tom



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Post Options Post Options   Thanks (0) Thanks(0)   Quote seawolf Quote  Post ReplyReply Direct Link To This Post Posted: January/29/2009 at 10:00
Originally posted by tahqua tahqua wrote:

Very nice, seawolf. I like both of them.
Did you do the camo work on the 77?
 
tahqua.
I would hardly call that paint spalshing camo work, but yes I have done it my self Big Smile
This is my go to rifle, it see a lot of dragging around, but it is light, accurate, strong and the 35 Whelen is an amazing caliber.
The Vari X III will be changed out with an Zeiss Victory 2,5-10x50, reticle #4 one of these days.
My old eyes demands better glass, and I have no plans to give up hunting Wink 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote seawolf Quote  Post ReplyReply Direct Link To This Post Posted: January/29/2009 at 10:10
Gunshow75.
It looks like I´m on the right track then "sensing" that bigger scopes gives better low light perfomance.
I always felt that the almost sexual obsession with exit pupils that some people have, was only a part of the story...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Jon A Quote  Post ReplyReply Direct Link To This Post Posted: January/29/2009 at 13:45
I also agree that bigger objectives can be "useful" at lower powers than many think.  If the exit pupil is exactly the same size as your eye's pupil, you have zero latitude in eye positioning before your pupil "misses some" giving a darker picture.  I've found a bit of extra exit pupil can give a more relaxed view that at least appears brighter under some uses.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Kickboxer Quote  Post ReplyReply Direct Link To This Post Posted: January/29/2009 at 13:59
Originally posted by Jon A Jon A wrote:

I also agree that bigger objectives can be "useful" at lower powers than many think.  If the exit pupil is exactly the same size as your eye's pupil, you have zero latitude in eye positioning before your pupil "misses some" giving a darker picture.  I've found a bit of extra exit pupil can give a more relaxed view that at least appears brighter under some uses.
I had never thought of the "why" in that way... one of those "well, duh, why didn't I think of that before" moments.  Good one.  Good comments. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote RifleDude Quote  Post ReplyReply Direct Link To This Post Posted: January/29/2009 at 18:39
Originally posted by Gunshow75 Gunshow75 wrote:

...I am pretty sure that Swarovski has introduced, or will soon introduce, a Z6, or Z6i, 2-12x,56 scope.
 
It's a 2-12X50 and they introduced it this year.  They also added 2.5-15X44, 2.5-15X56, and 3-18X50 models, in both Z6 and Z6i versions.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote RifleDude Quote  Post ReplyReply Direct Link To This Post Posted: January/29/2009 at 18:42
Originally posted by Jon A Jon A wrote:

I also agree that bigger objectives can be "useful" at lower powers than many think.  If the exit pupil is exactly the same size as your eye's pupil, you have zero latitude in eye positioning before your pupil "misses some" giving a darker picture.  I've found a bit of extra exit pupil can give a more relaxed view that at least appears brighter under some uses.
 
Very valid point, however, the 7mm figure often used is the optimum max dilation of a young, healthy iris.  The reality is that the max dilation of the iris of the average person past their 30's will be more like 5mm - 6mm.


Edited by RifleDude - January/29/2009 at 19:29
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Post Options Post Options   Thanks (0) Thanks(0)   Quote RifleDude Quote  Post ReplyReply Direct Link To This Post Posted: January/29/2009 at 18:55
Originally posted by seawolf seawolf wrote:

Rifle Dude.
I´m 63 years old, and my eyes have more or less the same age Wink
That means I do not have the same good eye sight as a young man.
 
For me the figuring of exit pupils and all the other numbers means less and less.
Practical use (and I do a lot of low light hunting) tells me that a low light scope starts at 50 mm.
 
I understand, but keep in mind that the original poster said he prefers a scope in the 2-8X class, and I don't know of any manufacturer making a 2-8X50.  So, given this criteria, recommending the bigger scopes isn't addressing his real question.  A 50 or 56mm objective is great for low light on a higher magnification scope that needs it for optimal performance.  A low powered scope does not need a 50mm objective to get all the light transmission your eye can use at the lower powers the scope offers.  If you have a 2.5-10X, 3-12X, etc., then yes, the 50mm or 56mm objective will provide an edge in low light performance.  But to just make the blanket statement that unless you have at least a 50mm objective your scope will be useless in low light is totally incorrect.  One look through my S&B 1.5-6X42 in the dimmest light, even when compared side by side to my Zeiss Diavari 2.5-10X50 quickly demonstrates this.  I hunt at night all the time for hogs, and my average shot distance is about 30 yards or so, so I usually use about 4X and seldom ever need more than 6X.  At these magnifications, my 42mm objective S&B is providing all the low light visibility my 50mm Zeiss will give me.  My own personal limit for objective diameter on a hunting rifle is 50mm.  Beyond that, I don't like the tradeoffs involved with the scope being mounted so high on the rifle, regardless of the small advantage I may gain in low light performance.  The 2 scopes mentioned above will do anything I need to do for low light or night hunting. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote lexmark Quote  Post ReplyReply Direct Link To This Post Posted: January/29/2009 at 21:52
I'm too tired to read through all of your answers, I understand that 50mm will give more light but will a 50mm lense make the view much wider than the 40mm?    or is the difference only minnor?
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