There are a lot of 40-44mm objective scopes out there as well as 50mm objective scopes. For low light hunting and shooting do the 50mm and above scopes really help that much with light transmission? There are some nice 56mm scopes out there also. Do they help that much more then the 40-44mm?
short answer in short NO. the reality is in low light you have trouble identifying the quality of animal you're shooting at if the distance is very far. if the distance aint that far, say 200 yards. you can simply dial the scope down to 4 or 5x in which case as long as its not a 70's redfield the glass should be decent enough to make the shot.
all the scopes I hunt with are capable of shooting well beyond legal shooting light.
Then why are mfgs making 56mm objective scopes????
What’s the market and purpose?
The riflescopes with 56mm objectives are usually high magnification riflescopes. You need a larger objective to get a usable exit pupil and for the increased image resolution.
For example, my current F-TR competition riflescope is a March-X 10-60X56 HM, which I use at 50X all the time. The exit pupil size is 1.12mm and this means I have to be properly behind this riflescope to see anything. The 56mm objective forms the image at the front of the erector tube with much more resolution than with the same glass in a 40mm, or 36mm, or 24mm objective, at the same focal length. You can go read about Dawes limit, if you want to learn more. The larger the objective, the greater the resolution (with all the applicable caveats). The downside is that the DOF is greatly reduced in a 56mm objective, compared to the 40mm, and smaller.
This scope at 50X provides me the detail that I need for shooting a 1000-yard competition on an NRA LR1FC target where the X-ring is 5 inches across, and I can distinguish each of the rings from the other concentric rings. I used the low power 10X when I first sighted in the riflescope, and I don't think I've ever used at less than 40X at first and then 50X for the last couple of years.
More recently, I have been testing a March-X 8-80X56 HM set at 80X on the same target. The exit pupil is a tiny 0.7mm, but that is not an issue when you are properly behind the riflescope. I have used it at 50X and 60X, but 80X is just too attractive to mess with the lower magnifications.
This is a different world and use from most of the users here. These scopes are much rarer than hunting scopes usually discussed here, but they have their users and that's why some manufacturers produce them.
I will also state that the exit pupil at the low end on these scopes (and probably most scopes with a base magnification greater than 3X) is definitely not what you would expect if you divided the objective by the low magnification. It's smaller, and sometimes a lot smaller.
