Posted on 07/03/2018 4:52:16 AM PDT by w1n1
If there's one question I receive, or view as a question posed on the vast expanses of the internet, it's "what scope should I buy?"
The resultant answers are usually comprised of about 95 percent useless information, whereas the remaining 5 percent is generated by folks who have a solid understanding of how to make a good choice with optics.
Optics aren't cheap, and it’s always a good idea to subscribe to the “buy once, cry once” policy when it comes to buying them. Why is that useless information percentage so high? Because there's an incredible amount of old and untrue information continuously being circulated throughout the shooting industry.
When someone presents the optics question to me, I cut right to the chase and ask them what they've budgeted.
I want to see where their expectations lie, which is going to help me direct them to certain brands that have the highest quality and feature rich products that fit that budget.
For the purposes of this article, I want to skim the surface and give you the information you need to know.
First off, if you’re looking for more light transmission, you're not going to get it from a bigger objective lens, or a bigger main tube. Those two items have zero influence on light transmission, which is one of the biggest misconceptions people have on rifle scopes.
Light transmission has everything to do with the refraction rate of the optical system, how many lens to air transitions the incoming light has to navigate before it gets to your eye, and the effectiveness of the coatings on the lenses.
There are a lot of optics companies out there that optimize the brightness and clarity of their lenses for in-store fluorescent lighting because that’s where the vast majority of scope purchasing decisions are made by the consumer.
The scope might look bright and clear in the store, but it might not be all you thought it would be in fading light when you’re trying to find that animal your buddy is trying desperately to talk you onto. Read the rest of this Rifle Scopes Guide here.
Thanks for posting!
Utter horse crap. This is like saying an astronomer can resolve the same image with a 10" telescope as with a 20'. The larger the objective lens, the more light transimission. This is simple physics. The issue with the bigger tube is a function of objective lens and focal length.
When dealing with the sizes of rifle scopes, this line is pretty much true. A larger objective lens gives you more field of view, not a brighter image.
My first reaction was the same as yours, but, strictly speaking, the author is correct. Light gathering capability is a function of objective lens diameter and is independent of light transmission (which is how much Light gets to your eye). These two properties work together to determine image brightness.
The two are inseparable. The larger the objective lens, the more light. The limitation is in restricting the amount of light that can be passed to the lens as in a hood or tube extension prior to the objective. You gain a larger FOV by increasing the degree of arc to the lens, that way you can reduce the tube diameter, but with this you run the risk of increased vignetting or distortion.
I try to always get a scope designed for air rifles.
Firearms have a single recoil back. Air rifles get 2 recoils, one forward and one backwards. The extra recoil is due to the spring (coil or pneumatic piston). The result is that firearms scopes on an air rifle will result in cracks on the edges of the lenses and optics over time, but an air rifle scope on a firearm will just take the beating and continue.
And although there are lots of cheap air rifle optics designed for $100 guns, there are also some very good air rifle optics that rival the firearms scopes in quality (and price).
Only through the introduction of filtering or coating the lens. Otherwise, all of the light that hits the lens will be transmitted (minus the minute amount lost due to absorption).
Bookmark for later, thanks for posting.
Light loss in the glass and coatings is not trivial. The total light transmittance through a material is equal to the total incident light less the light that is absorbed and light that is scattered. You also have the glues on doublet lenses increasing loss.
The curious thing is that the author claims manufacturers optimize their optics for in-store fluorescent lights, not light outdoors. That is hard to believe. Whenever I have purchased optics, the retailer or booth vendor has always allowed me to go outside to test. It amazes me that sometimes I can walk outside with a $2,000 pair of Swarovski binos without so much as leaving a driver license behind.
Bkmk
I purchased a PCP last year and while pricey, I love it. No recoil and very quiet.....
There's no limit on the number of optics available for it, it just comes down to what you want to spend.
I’m partial to Leupold products.
“I’m partial to Leupold products.”
Always a solid choice if you have the budget.
L
Anyone know? What’s the date on this Guide, and where is part 2?
Also, Bushnell sells a “Day & Night” scope series (IIRC the name) that supposedly has increased light gathering compared to other (regular) scopes, and this isn’t a true night scope. Anyone know how this is done, and is this hype, or true? Or true but insignificant?
... and amount of eye relief, and amount of reticle adjustment in MOA, and variable power, and parallax at different distances, etc.
Generally speaking, for two rifle scopes with the same quality of glass, and with the same magnification, the difference between a larger objective lens and the smaller objective lens is not brightness of image but field of view.
And that still increases brightness as more light is hitting the objective lens. Larger FOV is a function of the arc of the lens as well as diameter of the objective lens.
I was going to say the same thing.
I think we're butting heads over theory vs. practice.
Correct..! I was thinking maybe the cost in high quality optics is in the engineering of highly efficient lenses at a smaller and lighter weight.. (?)
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.