re: Let's Talk Optics!!

Why does it seem that everyone in this thread wants to hang Hubble telescopes on their rifles?

Here are a couple points to consider. First, the human eye can only dilate to about 7 mm when the eye is young, perfectly healthy, and pitch black. As a practical manner, aging eyes, and less than pitch black conditions means that dilation is usually more like about 5 mm and in daylight it will be about 4 mm. A 4x32 scope has an exit pupil of 8 mm and therefore, provides all the exit pupil anyone can use.

Secondly, scopes do not "gather" light. That is impossible. They transmit light and right now, the technological limit we seem to have reached with all the modern coatings is that about 92 percent of visible light is transmitting through the scope. That number is amazingly consistent through most all scopes that are fully multicoated from a $200 Burris up to a $2,000 Schmidt and Bender.

Where scopes can differentiate themselves is in the quality of glass used and some of the coatings. But it doesn't really provide a brighter image, just a clearer one that may allow you take advantage of the light transmitted a little better.

Finally, the high manification does not aid in shooting at reasonable distances out to 400 yards or so. One thing that high manification does is allow you to see a little better at low light. It is easier to see something that is close at low light than something that is far off and the higher manification helps and the big objectives keep a reasonable exit pupil at those high manifications. The thing is though, in the United States, night hunting, unless it is for hogs, is illegal so it really doesn't matter. The big 50 mm objectives and more were designed for Europe where they hunt at night.

The moral of it all is that in the U.S. the average hunter is better served by nothing bigger than a 3x9x40 that keeps the rifle light and well balanced while providing all power and lowlight shooting capability needed. You don't need an 18x scope to shoot a deer at 200 yards and the difference in available shooting time between something like a $200 Burris and a $2000 Schmidt and Bender set on the same power is going to be about a minute.