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Professional Security Cameras & Security Camera Systems at Reasonable Prices |
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CCTV Security Camera Lenses
Tips on CCTV security camera lens selection by Skyway SecurityHow to select a proper security camera lens in 3 easy steps and save money doing it?
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| CCTV Visual Lens Comparison Chart |
The following chart displays the comparison of CCTV lens with the regular 135mm film camera lens.
CCTV lens |
135mm lens |
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Focal Length |
Angle |
Angle |
Focal Length |
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2.5mm |
120° |
114° |
14mm |
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3.6mm |
92° |
94° |
20mm |
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4.3mm |
78° |
75° |
28mm |
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6.0mm |
53° |
51° |
45mm Standard lens for 135mm camera Regular angle of our eyes vision |
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12mm |
25° |
24° |
100mm |
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25mm |
18° |
18° |
135mm |
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| CCTV Technical Lens Comparison Chart |
Indicates total viewable area (WxH) at a given distance based on focal length used |
| Focal Length | 5' (WxH) | 10' (WxH) | 20' (WxH) | 40' (WxH) | 50' (WxH) | 100' (WxH) |
| 2.5 mm | 9.4x7.1 | 19x14 | 38x28 | 75x57 | 94x71 | 188x142 |
| 2.9 mm | 8.6x6.4 | 17x13 | 34x26 | 69x51 | 86x64 | 171x129 |
| 3.6 mm | 6.9x5.1 | 14x10 | 27x21 | 55x41 | 69x51 | 137x103 |
| 4.0 mm | 6.0x4.5 | 12x9 | 24x18 | 48x36 | 60x45 | 120x90 |
| 4.3 mm | 5.7x4.3 | 11x8.6 | 23x17 | 46x34 | 57x43 | 114x86 |
| 5.5 mm | 4.5x3.4 | 9x6.8 | 18x14 | 36x27 | 45x34 | 90x68 |
| 6.0 mm | 2.0x1.5 | 4x3 | 8x6 | 16x12 | 20x15 | 40x30 |
| 8.0 mm | 1.5x1.1 | 3x2.3 | 6x4.5 | 12x9 | 15x11 | 30x22 |
| 12.0 mm | 1.0x0.7 | 2x1.4 | 3.8x3 | 7.7x6 | 9.6x7 | 19x14 |
Use your 35mm camera and this chart to help make your lens decision.
| CCTV Lens Lux Chart |
Lux and low lighting chart |
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| Condition | Illumination | Details | |
| (FTCD) | (LUX) | ||
| Sunlight Full Daylight Overcast Day Very Dark Day Twilight Deep Twilight |
10,000 1,000 100 10 1 .1 |
107,527 10,752.7 1,075.3 107.53 10.75 1.08 |
Daylight Range |
| Full Moon Quarter Moon Starlight Overcast Night |
.01 .001 .0001 .00001 |
.108 .0108 .0011 .0001 |
Low Light Level Range |
| During the day the amount of illumination reaching a scene depends on the time of day and atmospheric conditions. Direct sunlight produces the highest-contrast scene, allowing maximum identification of objects. On a cloudy or overcast day, less light is received by the objects in the scene, resulting in less contrast. To produce an optimum camera picture under the wide variation in light level (such as occurs when the sun is obscured by clouds), an automatic-iris camera system is required. Typically, scene illumination measured in foot-candles (ftcd) can vary over a range of 10,000 to 1 (or more), which exceeds the operating range of most cameras for producing good quality video images. The chart above summarizes the light levels occurring under daylight and these low light level conditions. The equivalent metric measure of light level (lux) compared with the English (ftcd) is given. |
| 35mm to CCTV Focal Length Conversion Chart |
35 mm |
1/4" |
1/3" |
1/2" |
2/3" |
1" |
Angle |
10 |
0.9 |
1.4 |
1.8 |
2.5 |
3.7 |
120.6 |
35 |
3.2 |
4.8 |
6.4 |
8.8 |
12.8 |
53.2 |
60 |
5.5 |
8.2 |
11.0 |
15.1 |
22 |
32.6 |
85 |
7.7 |
11.6 |
15.6 |
21.3 |
31.1 |
23.3 |
110 |
10.0 |
15.1 |
20.1 |
27.6 |
40.3 |
18.1 |
135 |
12.3 |
18.5 |
24.7 |
33.9 |
49.4 |
14.8 |
160 |
14.6 |
21.9 |
29.3 |
40.2 |
58.6 |
12.5 |
185 |
16.8 |
25.3 |
33.9 |
46.4 |
67.7 |
10.8 |
210 |
19.1 |
28.8 |
38.4 |
52.7 |
76.9 |
9.5 |
235 |
21.4 |
32.2 |
43.0 |
59.0 |
86.0 |
8.5 |
260 |
23.7 |
35.6 |
47.6 |
65.3 |
95.2 |
7.7 |
CCTV focal length numbers shown converted from a 35mm camera zoom lens.
If you have any questions please email or call us: Toll Free Line: 1-877-476-6607 Email: info@skywaysecurity.com |
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