2

Before buying a pair of binoculars for hunting or birding or for astronomy, it is crucial to understand what do the numbers on binoculars mean. These numbers provide you with a wide range of information about the binoculars, all of which will help you to buy a pair that is right for you. Let's look at these numbers in more detail.

I found an old pair of Nikon reverse porro binoculars in a secondhand store this afternoon. The only marking is on the focusing knob: Nikon 8x24 7° The other end says Japan. The oval silver sticker on the body is completely illegible now. The imitation pigskin pouch also says Nikon and MADE IN JAPAN. It was out of alignment but I fixed that. Check Your Serial Number. The camera's serial number is the 7-digit number indicated by the red frame in the image above. If your D750 camera may be affected, as confirmed with the serial number check above, you will be provided with the necessary information to obtain service for this issue free of charge.

1. What do the Magnification Numbers on Binoculars Mean?

The magnification number on binoculars is expressed as part of a combination of two figures, for example 8x40 or 10x25.

The first figure (8x, 10x) refers to the power of magnification. Binoculars with an 8x magnification will make objects appear 8 times closer than they are. The higher the number, the closer objects will appear through the lenses.

Extreme magnifications (12x and up) make it difficult to maintain a steady image, unless you have the binoculars stabilized on a solid object like a table or a wall. You also get zoom binoculars, which offer an adjustable magnification range.

2. Objective Lens Size (Aperture)

The number following the magnification power is called the objective lens size, also referred to as aperture. This is a critical number, because it indicates how much light the lenses are able to gather. A 10x50 binocular will have a 50mm objective lens size, a 7x35 will have a 35mm objective lens size, etc. Wider lenses usually also increase the size of the binoculars.

The wider the objective lens size, the brighter the image you'll see thanks to more light being gathered through the lens. This number is most important for night sky viewing, or other low light conditions.

Here's a simple question to demonstrate this: which of a 10x25 or a 10x50 binocular will be best for viewing the night sky? The answer is, of course, the 10x50. You'll see many more distant objects in the night sky thanks to the wider aperture.

3. Understanding Angle of View

Angle of view walks hand in hand with field of view as they refer to the same thing: the amount of horizontal scenery that is visible when looking through the binoculars.

We will discuss them separately to avoid confusion, and show you how to convert one to the other if needed.

First, angle of view (AoV):

AoV is always expressed in degrees. The higher the number, the wider the area you'll be able to see. Anything over 6 degrees can be considered a good angle of view.

If you see a really high degree number, like 72 degrees, the manufacturer may be using actual angle of view. This number is reached simply by multiplying the angle of view with the magnification value of the binoculars.

Number

For example: a 10x50 binocular with a 7.2 degree angle of view will have a 72 degree actual angle of view (7.2 x 10 magnification).

4. Understanding Field of View

Field of view (FoV) is not expressed in degrees, but in either:

Again, a higher number simply means you'll have a wider horizontal view through the lenses. Typically you can consider a FoV of about 300 to 375 feet as adequate. Remember though that the higher your magnification, the smaller your field of view will be due to the object being brought closer.

Finally, here's how you convert angle of view to field of view:

Multiply the angle of view by 52.5

So, a 7.2 degree angle of view equals a 378 feet field of view

Lookup

7.2 x 52.5 = 378

7.2 x 52.5 = 378

5. Eye Relief Number

The eye relief number on binoculars is mostly important only if you wear glasses. It tells you how far away from the eyepiece your eyes can be while still being able to enjoy the full field of view that the binoculars offer.

If you wear glasses, you'd want an eye relief of at least 15mm.

6. Exit Pupil Number

The easiest way to understand this number is to hold a pair of binoculars about 8 inches from your eyes. The two dots you'll see in the center of the eyepieces are where the light from the lenses hits your eyes to allow you to see the image you're focusing on.

These need to be greater than your pupils. The value is easily calculated by dividing the objective lens diameter with the magnification. A 10x50 binocular will have a 5mm exit pupil, while an 8x25 will only have a 3.1mm exit pupil.

Anything larger than a 4mm exit pupil should be fine for most conditions, but bigger is better.

7. Close Focus

Our final entry in this article about what do binocular numbers mean is close focus. This number tells you the minimum distance the binoculars need to focus. For example, a close focus of 13 feet means you can get a perfect focus on an object as close as 13 feet to you.

A Quick Checklist

Now you no longer have to be daunted by the question of what do the numbers mean on binoculars. Let's give you a quick checklist to help you remember the most important points:

  • for night sky or low light viewing, a high objective lens diameter is important
  • greater magnification means a smaller field of view
  • look for an eye relief of more than 15mm if you wear glasses
  • an exit pupil of more than 4mm is recommended for night viewing
  • pay attention to a short close focus if you want to magnify very close objects

Conclusion

What does the numbers mean on binoculars? You now know the meaning of all the most important ones. Keep this guide handy when you shopping for binoculars to find the one that's right for you.

Get a nice big aperture if you want to see as many stars as possible, and a smaller aperture if lighter weight and portability are important to you. Beware of magnifications higher than 12x if you don't want too shaky an image without support, while also maintaining a decent field of view.

You'll be able to figure out all these considerations for yourself with the help of this guide. Good luck on buying the perfect pair of binoculars for your needs!

Furthur Reading: How to Choose Your Perfect Binoculars, Binocular Parts & their function


The following is a collection of serial numbers for large format lens manufacturers. For the most part, the information has been culled from Wilkinson, Glanfield and Wrights' magisterial Lens Collector's Vade Mecum, a data base available on CD-rom. Other sources of information include web-pages and anonymous information passed down to me through others.

There is a real absence of information on large format lenses. Of the contemporary makers, only Schneider has made a great effort to provide information, the other lens makers have been less forthcoming. However Rodenstock serial numbers, the other major European manufacturer, have been posted by Kerry Thalman. There are a few web-pages, both official and unofficial, for other three manufacturers, Congo, Nikon, (Unofficial and Official) and Fuji,(also here). However, serial numbers are, to my knowledge, entirely lacking.

Zeiss no longer makes large format lenses, and consequently has little interest or incentive to provide this information. Goerz, and Ross are long gone, and Voigtländer exists only in name. Taylor, Taylor & Hobson is also gone, although its one time subsidiary, Cooke, has recently returned to the fold, and is now making a 4x5 portrait lens. In any case, none of these companies provides any sort of information regarding the lenses they once made. This page is a modest attempt to provide one form of information, serial number-year correspondences.

Serial Number Lookup For Equipment

Nikon

Caveat: While I would like to make this collection as accurate as possible, I cannot make any claims as to the accuracy of any of the information. If you find something which you find of questionable validity, please do not hesitate to contact me. Or, if you have any information on large format lens serial numbers, for the manufactures list above, or any other, kindly forward them to me, and I will attempt to incorporate them.

Compur

From: Wilkinson, M, and C Glanfield. 2001. A Lens Collector's Vade Mecum, CD-rom Version 3F. Edited by A. N. Wright. Cornwall, UK: David Matthews Associates. Pages 65-66, Chapter 12


1912

2,700,000

250,000

3,200,000

The backbone of my army were Ramsters, which were Ram's mixed with Lobster's, I gave them the Ram's head front and hind legs giving them Horns, Herding, and charge attack, and gave them the Lobsters claws Back and Tail, giving them Barrier destroy, Regeneration, and swimming, they are a level 4 creature which destroyed pretty much anything they could reach. I was also inspired by the game Impossible Creatures, which I played a lot when I was young. Would very much appreciate it if you could have a look at my campaign:) Close. Posted by 2 months ago. I invented an evolution card game called 'Darwin's Choice', where players mix match over 400 animal cards. Impossible creatures best army rank. Whenever attacked, creatures with a Tarantula’s tail in your army will release a cloud of barbed hairs which will irritate and disorient any attackers near them, temporarily eliminating any organizational benefits those creatures possessed, such as hunting as a Pack, or moving defensively as a hHerd.

1935
1920

3,750,000

500,000

4,250,000

1937
1925

4,850,000

750,000

5,400,000

1939
1927

6,000,000

950,000

6,200,000

1948
1929

6,500,000

1,150,000

7,000,000

1950
1931

7,700,000

1,800,000

8,500,000

1952
1933

From: http://www.sci.fi/~animato/lumiere/lumiere.html

450000
500000
600000
750000
850000
950000
1000000
1150000
1500000
1800000
2250000
2700000
3200000
5400000

.

Goerz American Optical Company

From Eddie Bolsetzian (former Goerz Tech.) provided by Michael Buchmeier, on the Large Format Home Page, More on classic lenses.

70001-1409351902-1903
150000-1901701903-1905
200941-2242671906-1908
223775-2266301908-1909
310001-3157341911-1914
315735-320000 1914-1918
751240-756909 1927-1937
7553001934
756910-7657301937-1945
765730-771199 1945-1948
771200-780169 1948-1954
791500 ~1955

.

Ross

From: Wilkinson, M, and C Glanfield. ibid, Pages 87-88, Chapter 11

Nikon Usa Serial Numbers

1840
86,000
1918
1850
95,000
1921
1860
100,000
1924
1870
105,000
1925
1875
110,000
1927
1880
115,000
1930
1885-1890
120,000
1931
1890-1895
125,000
1933
1911
140,000
1939
1918
200,000
1947
1921
213,000
1946-7
1924
250,000
1960
1925

.

Taylor, Taylor & Hobson

From: Wilkinson, M, and C Glanfield. ibid, Page 71, Chapter 13

1001895
5,0001900
19,5001914
71,0001918
117,xxx1926-7
250,0001939
303,xxx1944
300,xxx1947
688,03x1965


Voigtländer

From: Wilkinson, M, and C Glanfield. ibid, Pages 6-9, Chapter 14
see also: http://members.aol.com/dcolucci/sn.htm

05/1840 First Petzval Portrait produced
1796-184?, Marked 'Voigtländer & Sohn in Wien'

Nikon Serial Number Check

Year
Year
4033139,108
1917
5000142,853
1918
10,000144,419
1919
27,449154,426
1920
30,000160,008
1921
31,000172,136
1922
32,000194,086
1923
34,000216,948
1924
36,000227,929
1925
38,000 - 39496248,505
1926
40,000279,710
1927
41,911365,562
1928
43,685537,338
1929
45,431671,174
1933
46,454803,220
1934
47,7711,026,690
1935
49,0842,000,000
1937
54,1682,718,530
1942
54,8962,700,000
1945
65,6913,000,000
1947
68,1933,220,000
1951
70,6823,300,500
1952
72,6383,461,400
1953
75,4793,600,000
1954
79,2883,731,000
1955
83,4774,001,000
1956
88,0574,303,000
1957
97,9994,514,000
1958
101,6494,802,000
1959
105,7785,033,000
1960
110,3475,473,000
1961
113,5695,900,000
1962
118,634 - 125,9756,219,000
1963
126,0016,423,000
1964
132,7266,664,222
1965
137,6829,999,999-10,000,150
1971

.

From: Wilkinson, M, and C Glanfield. ibid, Pages 99-101, Chapter 17

Carl Zeiss Jena Serial Numbers
See also: http://home.sprynet.com/~stspring/Zeiss%20Ikon.html

Serial NumberSerial Number
Year
173,418-200,520903,100-908,150
1928
208,473-249,350919,794-1,016,885
1929
249,886-252,739922,488-1,239,697
1930
282,800-284,5001,239,699-1,365,582
1931
285,200-288,1001,364,483-1,389,279
1932
289,087-298,1571,436,671-1,456,003
1933
298,215-322,7481,500,474-1,590,000
1934
322,799-351,6111,615,764-1,752,303
1935
375,194-419,8231,674,882-1,942,806
1936
433,273-438,3611,930,150-2,219,775
1937
422,899-498,0062,267,991-2,527,984
1938
561,270-578,2972,527,999-2,651,211
1939
631,500-578,2972,652,000-c2,678,000
1940
631,500-648,5002,678,326-2,790,346
1941
666,790-703,1982,800,000- ?
1942
722,196-798,251

.

Carl Zeiss Jena, East Germany

Number
1945-1949
3,200,000-3,470,000
1949-1952
1952-1955
4,000,000-5,000,000
1955-1958
1958-1961
6,000,000-6,000,0001961-1964
7,000,000-8,000,0001964-1967
8,000,000-9,000,0001967-1970
9,000,000-10,000,0001970-1975

Nikon Camera Serial Number Database


Carl Zeiss (Opton), Oberkochen, West Germany.

Nikon Binocular Serial Number Lookup 700

10,000-500,0001946-1951
500,000-1,100,0001951-1953
1,100,000-2,600,0001953-1959
2,600,000-3,000,0001959-1961
3,000,000-4,000,0001961-1965
4,000,000-5,000,0001965-1969
5,000,000-6,000,0001969-1971
6,000,000-7.300,0001971-1975