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<h1>Lenscalc - Online Lens Calculator</h1>
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Lenscalc is a universal tool designed to eliminate the frequent errors, mis-readings and interpolation problems from using traditional lens calculators. The calculated tables can be simply pasted directly into a spreadsheet or word processor or printed for a permanent record.
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LensCalc instantly overcomes the tedious job of calulating the relationship of target size to screen percentages, required by many tender documents. Anyone tendering for or installing CCTV where the correct lens selection is important will find LensCalc invaluable.
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<li>Any combination of focal length, lens angle, % screen height and distance can be calculated from any two factors, where the target height is known.</li>
<li>The target height itself is a variable that can be set for different situations and all the relevant factors calculated.</li>
<li>Table 1: Calculates the camera distance needed to fill a percentage of the screen witn an object (i.e. person), from the lens focal length.</li>
<li>Table 2: Calculates the camera distance needed to fill a percentage of the screen witn an object (i.e. person), from a lens lens angle.</li>
<li>Table 3: Calculates the percentage of a target on screen from the focal length of the lens and the distance of the target.</li>
<li>Table 4: Calculates the focal length needed to achieve a required target percentage on screen from the distance of the target.</li>
<li>Table 5: Calculates the scene size on a monitor from the scene distance and focal length of the lens.</li>
<li>Table 6: Calculates the area of view from camera height and lens angle, results show required downward angle and blind spots for multiple cameras.</li>
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