|
Brunton Epoch
Zoom |
Brunton Epoch Compact |
Brunton Eterna Compact Scope |
Brunton Eterna Monocular |
Brunton Echo
Pocket Scope |
Brunton Macroscope |
|
 |
 |
 |
 |
 |
 |
Features
|
|
|
|
|
|
|
| Magnification / Power |
8-15x |
8x |
18-38x |
6x |
7x |
7x |
|
| Objective Lens (mm) |
35 |
21 |
50 |
30 |
18 |
40 |
|
| Exit Pupil (mm) |
4.4 @ 8x
2.3 @ 15x |
2.6 |
2.8 @ 18x
0.8 @ 38x |
5 |
2.6 |
5.7 |
|
| Close Focus (ft) |
6 @ 8x |
6 |
20 |
12 |
1.1 |
1.5 |
|
| Field Of View (ft @ 1000yd) |
273 @ 8x |
393 |
141 @ 18x
68 @ 38x |
341 |
181 |
336 |
|
| Eye Relief (mm) |
17 |
15 |
16 |
19 |
12 |
15 |
|
| Prism & Optics Glass |
SF |
SF |
ED Glass
BaK-4 |
BaK-4 |
BaK-4 |
BaK-4 |
|
| Glass Coating |
Phase coating
AL-HR Reflective
FlatLight full Multi coating
Anti-Fog lens |
Phase coating
AL-HR Reflective
FlatLight full Multi coating
Anti-Fog lens |
Emerald Fire full multi-coating |
Emerald Fire full multi-coating |
Multi-coated |
Emerald Fire full multi-coating |
|
| Nitrogen Filled |
Yes |
Yes |
Yes |
Yes |
No |
Yes |
|
| Waterproof / Fogproof |
Yes |
Yes |
Yes |
Yes |
No |
Yes |
|
| Tripod / Monopod Ready |
Yes |
No |
Yes |
No |
No |
Yes |
|
| Dimensions |
6x5.2x2.2"
15.2x13.2x5.5mm |
4.3x4x1.5"
10.9x10.1x3.8cm |
8.1x4x4"
20.6x10x10cm |
6x2x1.9"
15.2x5.1x4.8cm |
3.3x1.3"
8.4x3.3 cm |
6.5x2.6x2.5"
16.5x6.6x6.35 cm |
|
| Weight |
32oz
909g |
13oz
369g |
24oz
682g |
11.5oz
327g |
1.8oz
51g |
11.3oz
321g |
|
| Other Special Features |
Magnesium alloy frame w/ ergonomic body armor
Variable speed focus
Locking, multi-step eye relief system (eyeglass compatible)
Locking diopter adjustment
HALO
Unlimited lifetime warranty
|
Alloy frame with ergonomic body armor
Locking, multi-step eye relief system (eyeglass compatible)
Locking diopter adjustment
HALO
Unlimited lifetime warranty
|
Alloy frame with ergonomic body armor
Sight alignment tube
Includes ineractive Neoprene case
|
Alloy frame with ergonomic body armor |
Not much larger than your thumb! |
Polymer frame with ergonomic body armor
Twist-up eye relief system (eyeglass compatible)
Large focus wheel for easy one-hand use
|
| Outpost Price |
Check |
Check |
Check |
Check |
Check |
Check |
Optics Glossary & Selection Criteria...
Magnification (or Power)
The numbers you see on the side of binoculars and scopes describe two important aspects of the optics. These numbers usually appear as "7x50". The first number refers to the magnification, which in this example would be 7 times - objects will appear 7 times closer. The second number refers to the diameter (in millimeters) of the objective lens which is the large lens at the front of the binoculars or scope. A number such as "8-15x35" refers to an optic with zoom capabilities, which in this example would be variable between 8 & 15 times.
You may be thinking that a more powerful magnification is usually the best choice, but this is not always the case. It will depend on how you plan to use the equipment. You may be familiar with the shaking image that happpens when you use your camera at its highest zoom power. The same will happen with binoculars and scopes, so with higher power comes the need to use other gear such as tripods to make your viewing clear and stable.
Another problem with high power optics is that often they will have a narrow field of view, making them much more difficult to use with moving targets like birdwatching. They may also require a larger objective lenses which result in larger, and heavier gear.
The size of the objective lens plays a key role in the light gathering capabilities of the binoculars or scope. The larger the lens, the more light it can gather, and consequently the brighter the image. The discussion of 'Exit Pupil' will cover this issue further.
Exit Pupil
This term refers to the small disk of light you can see on the surface of the eye pieces when you look at the end of your binoculars or scope. The exit pupil is therefore the total size, or amount of light that will be reaching your eye. The size of this exit pupil is easily calculated by dividing the size (in millimeters) of the objective lens (front lens) by the overall magnification of the binoculars or scope. For example, binoculars with parameters 7x21 have an exit pupil of 21/7=3mm.
How is this important? Well, it relates to the overall brightness of the optic. The larger the exit pupil, the brighter the image will appear. Our own eye pupils will range between 1-7mm depending on the lighting conditions, so an exit pupil on a sports optic of about 5mm will provide a bright image over a wide range of applications, 7mm exit pupils will perform better in low light, and smaller exit pupils of less than 3mm will work fine in bright outdoor conditions. Since the exit pupil is related to objective lens size, it becomes a matter of whether you want to carry larger, heavier optics in order to have the better low-light performance.
Field of View
As mentioned earlier, the field of view is related to the magnification of the optics. The field of view is typically expressed in feet @ 1000 yards, which means you can see perhaps a 350 foot wide scene off at a distance of 1000 yards.
Close Focus
This is how close an object can be and still remain in focus. Many optics cannot focus very close to themselves. The Brunton Macroscope is one model that is designed for close-up viewing.
Lens Coatings
Coating are special materials applied to the surfaces of lenses to reduce distortion and reflection. There may be single coatings or multiple coatings depending on the level of sophistication of the optics. A models that simply indicates "Coated" would mean that at least one lens surface has been treated. "Fully Coated" would mean that all air-to-glass surfaces have been treated. A phase corrected coating (on roof prism binoculars only) addresses a distortion effect.
Eye Relief
This is the distance from the surface of the eyepiece at which you can still see the entire field of view. This becomes important if you wear eyeglasses and would prefer to not have to remove them to look through the binoculars or scope. Long eye relief is considered anything over a distance of 14mm
Prism Glass Types
The light transmission capability and inherent distortion of a lens is a product of the quality of the galss used. Without getting into too much gory detail, the most common glass types used in sport optics are the BaK-4 and BaK-7. BaK-4 offers better color and light transmission, but comes with a higher price tag. The top of the heap is SF prism glass which has the best light characteristics and the least distortion.
Back to...
Optics Department >
|
