Lens calculator?? Reading direction?

[ebg 0]

Hi,

 

I am a bit confused when it comes to calculate viewing angles.

Have used several lens calculators and they talk about "reading direction"

When I change this value the viewing angle change lots.

Could anyone pls explain how this works? What will I get when I buy a camera?

 

I'm looking for a outdoor camera with IR and at least 80 degrees viewing angle.

 

Will a 1/3 CCD with 4.0 be enough, or is 3.6 or 2.8 needed?

 

Thanks much,

Roger

[survtech 0]

80 degrees horizontal (width)? With a 1/3" sensor, you would need a 2.8mm lens. 2.1mm for a 1/4" sensor.

[ebg 0]

Thanks much,

So in most cases only the horizontal is important, for some the vertical? Cannot see many having use of the diagonal. The confusing part is some camera resellers claim the diagonal value and doesn't mention anything else while others claim the horizontal.

 

One example is 1/3 CCD with 6.0 mm (=43.6 deg horizontal, 53.1 deg diagonal) and they claim 60 deg. Could this even be possible? Can you create a standard camera that can handle larger angles than the above?

 

Thanks again

Roger

[suky 0]

Hello, Roger, If you require for 80 degree's viewing angle with 1/3" CCD, I think you need a 2.8mm Lens, for the camera's viewing angle is 81.2 degree, being with 2.8mm lens and 1/3" CCD.

 

 

You can try this one, it is easy to use..

 

http://atvideo.com/Support/tlFOVCalc.htm

[survtech 0]

We commonly use Computar 1.8-3.6mm and Pelco 1.6-3.4mm varifocal lenses. The 1.8-3.6mm can give a horizontal field-of-view of around 105 degrees and the 1.6-3.4mm around 110 degrees. The effect is a bit fisheye but it is useful for some situations.

[ebg 0]

Thanks much

[thewireguys 3]

http://computarganz.com/p.cfm?s=31&p=340

 

 

This should also help.... Computar lens calculator

[hardwired 0]

Here's an online calculator from Pelco... Lets you calculate field of view or lens size either way.

 

http://www.pelco.com/support/tools/lenscalc.aspx

[bruce 0]

man

 

 

This gonna be helpful, thank you so much