Bigger then 40mm objective
- Thread starter 300_WSM
- Start date
Umm, no, I have 30mm, 36mm, 40mm and 56mm objectives. The 56's are great in poor light.
x2 I dont know the science of it,but i do know that if you had a scope with say a 8.5mm exit pupil,it would be more than the human eye can dilate to.Doesn't have an effect on what you see but does mean it will be alot brighter in low light conditions.
migrant hunter
CGN Ultra frequent flyer
- Location
- Southern Alberta
Roughly speaking, the human eye can take about 7mm of light. The figures for you scope should be devisable by 7 ie 6x42,(7x50), 8x56
This is why some scopes have parralax adjustment for when you turn the magnification up and your figures are no longer multiples of 7.
Many European hunters use way bigger front lenses (50 or 56 mm) rather than the 40mm so common here. I have three 50 mm scopes and they're a lot easier to see through than a 40!
This is why some scopes have parralax adjustment for when you turn the magnification up and your figures are no longer multiples of 7.
Many European hunters use way bigger front lenses (50 or 56 mm) rather than the 40mm so common here. I have three 50 mm scopes and they're a lot easier to see through than a 40!
The guy at work doesn't have the whole story, so he's wrong. As Dogleg suggested, the thing that guy thinks he is talking about is the exit pupil. This is determined not just by the size of the objective lens, but also the magnification. Divide the objective lens size by the magnification to discover the exit pupil. If the exit pupil is larger than the maximum dilation of your pupil, there is some wasted light. With variable power scopes, some settings probably have a larger exit pupil than you can fully use, and some will be smaller, actually restricting the light. But that doesn't mean they are no good on those settings.
As migrant hunter said, the typical maximum dilation of the pupil for most people is about 7mm, so an exit pupil larger than that is giving you more light than you can use. That means it's silly to put a 50mm objective lens on a 4x scope because you are carrying weight and bulk for no good purpose, but if that scope is variable power, that big bell is giving you light you can use on the higher settings, so then it does make sense.
However, as we get older, our maximum pupil dilation usually gets smaller, part of the general aging process that means most of us will eventually need glassses, if we live long enough. Typical maximum pupil dilation in your 40s is about 5mm, so if your optics produce an exit pupil bigger than that is wasted on you. But you can still use all the light your 50mm lens can transmit at 10x, so if you feel a 50mm or 72mm lens isn't too much trouble to carry, go ahead.
(Remember also that better quality glass and lens coatings can enhance light transmission, so you may get a scope that is more than bright enough for your use without going to the biggest size of objective lens.)
And if you are trying to take a shot at last light and the sight picture is a little too dark to feel sure, try turning the magnification down to the lowest you think you can use, and you may find there is enough light after all.
As migrant hunter said, the typical maximum dilation of the pupil for most people is about 7mm, so an exit pupil larger than that is giving you more light than you can use. That means it's silly to put a 50mm objective lens on a 4x scope because you are carrying weight and bulk for no good purpose, but if that scope is variable power, that big bell is giving you light you can use on the higher settings, so then it does make sense.
However, as we get older, our maximum pupil dilation usually gets smaller, part of the general aging process that means most of us will eventually need glassses, if we live long enough. Typical maximum pupil dilation in your 40s is about 5mm, so if your optics produce an exit pupil bigger than that is wasted on you. But you can still use all the light your 50mm lens can transmit at 10x, so if you feel a 50mm or 72mm lens isn't too much trouble to carry, go ahead.
(Remember also that better quality glass and lens coatings can enhance light transmission, so you may get a scope that is more than bright enough for your use without going to the biggest size of objective lens.)
And if you are trying to take a shot at last light and the sight picture is a little too dark to feel sure, try turning the magnification down to the lowest you think you can use, and you may find there is enough light after all.
migrant hunter
CGN Ultra frequent flyer
- Location
- Southern Alberta
This could be why I found that moving from the UK to Canada there's a big difference in what scopes people use.
Because in the UK/Europe people own fewer rifles per person(more firearm restrictions) and they are more likely to hunt in low light(less restrictions on hunting first/last light) they seem to use higher quality, bigger objective scopes(Swarovski being a good example)
Over here, more people use 40mm objectives, but higher magnification.
I bought a leoupold varmint hunter(40mm) in the UK for my .243 and took it off again after a couple of months as I could see deer(melanistic/black fallow deer in heavy softwood cover) in my binos and could'nt find them in my scope.
Because in the UK/Europe people own fewer rifles per person(more firearm restrictions) and they are more likely to hunt in low light(less restrictions on hunting first/last light) they seem to use higher quality, bigger objective scopes(Swarovski being a good example)
Over here, more people use 40mm objectives, but higher magnification.
I bought a leoupold varmint hunter(40mm) in the UK for my .243 and took it off again after a couple of months as I could see deer(melanistic/black fallow deer in heavy softwood cover) in my binos and could'nt find them in my scope.
