optics

Can some one either explain to me, or point me to where I can read about the explaination, the difference in optics (scopes, binoc's, etc.). I know the first set of numbers refers to the number of times of magnification. But what is the second number refer to, and what makes the differrence between a good set and a poor set. For example why would a set of binoc's 20x80mm not necessarily be as clear or as good as a different set with only a 12x40mm? How do you go about choosing a strong enough set for your needs and still maintain quality? Thanks.

Lots of opinions on this one. The second number is somehow related to the field of view. A larger number translates to a larger set of binocs which usually translates to more weight. So even if it does gather more light, you have to decide if hunting during non-legal hours is worth carrying them around all day with you. Hopefully you shoot the deer before sunrise and don't have to carry them :o)

Seriously though. I'd be more concerned with light gathering capability which is usually due to the coating on the glass. More expensive binocs will usually have multi coated lenses. There are a couple of different process though. Just the mere fact that one set has more coatings than another does not necessarily mean they gather more light. Light gathering is important in the twilight hours. You'll want to be looking for deer as they move around before going to bed down in the west. Not so important in a tree stand. So your hunting habits dictate the type of glass you'll want too.

Keep in mind that super powerful binocs look neat in the store and give a lot of detail when you try and read the signs in the shoe department from the hunting counter. In reality though, in the field, you will loose clarity as you shake the binocs while trying to hold them steady. Typically a deer hunter will use a 7 to 10 power binoc...8 being the most popular. I use a 10 power. I still hunt in the west in open sage brush country and I want to be able to spot a deer that might be a mile away. I use my spotting scope(40-60 power) to count the tines. Most hunters think that 10 power is ridiculous.

If your navigating a ship on the ocean, you may want those 22 power binocs. They also come in handy at a ball game. And they really look neat at the store. But that's about all I'll say about that before someone comes along and tells us both that they use 40 power binocs to hunt ground squirrels.

I found a nice compromise in the Leopold, Wind River line of binocs. Take a close look at them. They are available in 6-12 powers and they have roof prisms as well as porro prisms (roof prisms are the ones with straight barrels and typically are the compact units and more pricey).

This is in no way meant to be an answer to your question. Just stuff to think about as you search for your answer. And hopefully guide you to some answer.

In your example, the first number (20) is the magnification, the second (80) is the objective lens size. Anything above 12x would be very difficult to hold steady enough to be useful in the field IMO. Anything over a 40mm objective tends to be too heavy to carry very far. The most common used in hunting are 7x35, 7x40 and others in that range.

The difference between a good set & a poor set (technically speaking), is in the quality of the glass, the design, ability to focus. The quality of the glass is usually what makes the most difference. The better the quality, the longer you can use them before your eyes start to hurt. Poor quality glass has more distortion that your eyes naturally try to correct. After a while, the muscles that try to make the correction get tired.

Just this layman's attempt at an explanation. Roy D

If you want to read about hunting optics, a book titled'Optics For The Hunter' by John Barness will tell you all you want to know and then some. It is a very good investment.