Home Forums Hunting & Shooting Hunting Optics light gathering?

No scope gathers light, it only transmits light. Glass quality is the key to good optics.

You may be right about the different species AND different world.

I've been at this for quite a long time and I've got no good explanation for his particular type of persistent ignorance.

As far as the brightness goes, that gets a little tricky since apparent brightness depends o a lot of things, light transmission not ranking very high among them as far modern scopes are concerned.

Apparent brightness to a human is something else yet, since perceptual issues come into play.

ILya

Correct and when it comes to older eyes and brightness being an issue, often the older eye has had their lens become faded due to years of sun exposure. They just don’t see the world as brightly. Add in subtle changes that occur with early cataract development and it gets worse.

Most that get a cataract replaced are immediately aware of how much brighter colors and the world has appeared to become. With the older eye there is often more going on than exit pupil with regards how bright things appear.

ILya,

Have done a lot of "brightness tests" with several different people looking through the same lineup of binoculars or scopes, and while in general they ranked them the same, the big differences were in color perception. And of course both varied with the ages of the testers.
Which is the reason one of my other tests uses a black-and-white chart, which leaves color perception out of the equation.

Have also covered up the brand-name on occasion to prevent "origin bias" when using other people to test optics. It's amazing how some people believe a binocular or scope with a certain brand-name simply has to be great--or bad.

One interesting non-optical test I ran across many years ago had people tasting wine out of bottles with different prices, even though the pric tags had nothing to do with the real-world price. In general, they did pick more expensive wines as tasting better--but that was only part of the test The folks who ran it also hooked the tasters' brains to sensing devices, and it turned out the brains of the tasters who picked cheaper wines actually registered more activity in the "pleasure center." So perceptions of "value" can actually affect our sense of taste. I would guess this also applies to sight, at least on a general level, as in "Oh, wow! This binocular's sure bright!"

Working in the soft drink industry for over 40 years, this is evident in every purchase made by a consumer whether it is beverages, optics or automobiles. More is placed on perception than actual value. In a blind taste test, between Coke, Pepsi and Ginger Ale, most people couldn't tell a difference...

Not surprised at all. I would add refined fuels to the list, especially gasoline. People will tell you they prefer Brand X over Brand Y, and that any branded fuel is superior to the unbranded fuel, but in reality it is all the exact same stuff, coming from the exact same huge storage tank at the refinery or terminal. Only difference is each major oil company will put a "marker" in the fuel so that when they test it they can tell if you have their fuel in your tanks. "RaceTrack sucks, Chevron rocks"......it's the exact same spec'd fuel.

If people only thought rationally, I'd be out of a job.

Black and white charts are very limiting in terms of what they can show you and if that is what you use, you have to have a LOT of differently sized features and several different illumination levels. Otherwise, it is not a hugely informative test.

One interesting development for tests of this type is something called TOD: Triangle Orientation Determination. It turns out that if you look at a series of triangles of varying sizes and try to determine which way they are pointing you end up with a much more repeatable test than if you are looking at line-pairs.

A lot of the differences between how we perceive images come down to color perception, contrast and shape differentiation. Human brain is remarkably good in seeing common geometric shapes, sometimes even where there are none.

Perception bias is a very real thing. The funniest wine related test I have seen was when they added some tasteless red coloring to white wine and all the wine snobs were absolutely convinced it was the greatest red wine ever and they could not figure out it was the same thing as the white wine that was in another glass.

On the other hand, many of the differences are real. I work in the industry where there are a lot of people with good eye for images who know nothing about binoculars, scopes, etc. I have done this test many times with different binoculars having taped up the brand. In most recent one of these, looking at a bunch of 8x42 binoculars, every single person thought Leica Noctivid (the only alpha bino in the line-up) was head and shoulders better than everything else there.

Generally, a human eye is a very poor imaging instrument, while human brain is absolutely unparalleled as an image processor. When I go hunting with a friend of mine who is a lifelong hunter (while I am comparatively new at it) he can see game much earlier than I can, although my vision is objectively better. His image processor is much better at identifying game animals than mine is.

ILya

My deer antler comparisons have nothing to do with "brightness". It comes down to can you see the long tine well enough that you would call it a legal buck and shoot. My Swarovski might be a little brighter than my buddy's Nightforce but the Nightforce lasts a couple minutes longer on the deer antlers.

you may want to think about that statement a little more....

I am a rather dense fellow. If you want me to get what you are talking about you might want to be less ambiguous.

I think he is suggesting your scope to identify game is very poor form. You would not get a second chance in the people I hunt with.

You said it! You are next to depleted Uranium on the element chart...

Doggone it, now that this discussion has gotten so deep, and Ringman has added his brilliance to the fray I'm going to have to go out and get a Paper towel tube and put clear tape on each end of it to see if it is as bright as my Leupold binos. I may have just wasted a lot of money on semi-expensive glass over the years when I could have gotten by with home made objects because my brain and eyes apparently can't tell the difference...

Ringman, which newspaper was it you use for your test? The New York Times, or the Nickle ads? Once the snow clears a bit I'm a going testing.....

Bob

Ilya,

Yes, I am very aware of the limits of B&W charts--which is why they've only been one of the methods I've used to test brightness, along with availing myself of the really expensive equipment in the labs of various manufacturers.

But in recent years I've almost entirely quit testing hunting scopes for "brightness," because all the tests showed there's very little difference in modern, fully multi-coated scopes--and the fact that reticle visibility makes far more difference.

Let's let him tell us what he meant.

I guess you never have verified with your scope before you fire. Since I prefer to hunt alone I will not miss your un-invite. I want to be safe and legal.
If I don't impress my .com friends with my hunting style, I am not disappointed since I don't try to impress them.

I guess you didn't read the post so you could attack intelligently. The low light comparisons are done using deer antlers 131 yards away in the woods.

To be fair, you can't really test a scope for brightness using a black and white chart. You can get some crude measure of resolving ability if the chart is done right and a little bit of contrast. That bit of contrast is going to have a fairly profound effect on how bright a scope appears.

I do agree that reticle visibility has the most profound effect on how well a scope works in low light, although increasingly well implemented reticle illumination in many scopes really helps with that.

I do not a whole lot of instrumental testing with riflescopes these days either, but if I find something that bears further investigation, I take the scope to work and take a closer look.



ILya

I don't have any experience with all the high tech testing but I did learn a lot last year while hunting one evening in NE Montana. It was the 3rd or 4th evening of my hunt so my outfitter came along with my guide and I to try and get me on a nice animal. It was fairly overcast so dark was coming in quick. In the last 10 minutes of legal shooting light, a string of mulies finally came walking through at around 100 - 120 yds. I had a new set of Leupold BX-4 10x42 (which up to this point I thought were fantastic), my guide had a set of Steiner's in 10x42 (Predators maybe) and my outfitter had his Swaro EL 10x50's. My guide could make out bodies with a couple of them probably having horns. Through my BX-4's, I could definitely tell which were bucks but not well enough to judge quality. My outfitter said that one of them looked marginal with a decent spread and tine length and thought we could probably do better, but if that was what I was looking for I was welcome to take the animal. He handed me the Swaro's, and while they weren't "magically" brighter, there was just enough difference for me to see that he did have a decent spread but could have been a little heavier. The outfitter seemed happy that I passed on the animal saying he probably needed another year. The next morning he put me on a nice 150" 4x4 with brow tines. My first mule deer but hopefully not my last.

I've been hunting with Leupold binos for over 20 years and they had never let me down before. I know that was 10x42 vs 10x50, so how much difference was glass quality and how much was the larger lenses I'll leave up to Mule Deer and others with more experience to educate me. I have done some additional reading and learned that when it comes to the big 3, Zeiss SF, Swaro EL and Leica Ultravids, my eyes probably aren't good enough to ever tell the difference. I do know that on this year's hunt for a Wyoming mulie, I will be carrying a set of the Zeiss SF's. These just seemed to fit me better than the other 2.

Again, it ain't light gathering, it's light transmission. Light comes in the objective end, goes through all the crooks and crannies and through the lenses and the amount of light that gets out to the ocular lens as opposed to what came in can be calculated as percentage of light transmission. Only what goes into the objective is gathered. Nothing is gathered within the scope.