what has wider angle 2.8-12mm or 5-50mm

[jeffm0927 0]

I have both cameras and want to put one above my driveway which is only about 8 feet above. want to capture about a 8 ft wide driveway. which is better to use for wider angle ? the 2.8 or the 5. these are vari-focal lenses as you see.

[Campbell 0]

I have both cameras and want to put one above my driveway which is only about 8 feet above. want to capture about a 8 ft wide driveway. which is better to use for wider angle ? the 2.8 or the 5. these are vari-focal lenses as you see.

 

2.8. Although you should test it first to see what is most suitable for your environment. You may find that your 5 has enough width to cover what you need in greater detail.

[Numb-nuts 1]

Generally speaking, the smaller the figure the wider the angle but that is not quite it.

a 2.8 mm lens has view angle of 129 deg. and a 12 mm lens has a view angle of 28 deg. a 6 mm lens an angle of 32 deg and a 50 mm an angle of approx 5.5 degrees.

 

How far from your target will your camera be, and what size is the sensor 1/4", 1/3" or 1/2" ?

We already know that the target width is 8 ft, (possibly 9 ft) now go to the lens calculator here and fill in the gaps. You should then have a rough idea which of the varifocal lenses matches your needs more closely.

Unless you have a ranch, the smaller would be my guess, however, they should both do what you want, but there is no substitute for trying it out first. Your dealer should be happy to set up a demo for you if you commit to buying one or the other.

 

It's easy enough to set out a target to set up the camera before installing it. Set up your target (Could be a friend standing at a location) on the ground and mark out the width and the camera distance from the target Now focus on the target until it fits your setup. You might like to put tape over the vari-focus and iris knobs if they are external, and easily upset. You're ready to fit the camera!

 

Love to see a pic of the 5-50mm camera.

[Soundy 1]

I have both cameras and want to put one above my driveway which is only about 8 feet above. want to capture about a 8 ft wide driveway. which is better to use for wider angle ? the 2.8 or the 5. these are vari-focal lenses as you see.

We can't really tell you "which is best" because the two have overlapping ranges and truthfully, either should work fine - between 5 and 12mm, both will give identical coverage (assuming both use the same size sensor). A better idea might be to decide which might be better for something else (whether you need a wider or tighter shot for another area), then use the leftover one for this area.

[Securame 0]

Generally speaking, the smaller the figure the wider the angle but that is not quite it.

a 2.8 mm lens has view angle of 129 deg. and a 12 mm lens has a view angle of 28 deg. a 6 mm lens an angle of 32 deg and a 50 mm an angle of approx 5.5 degrees.

 

Where did you get those numbers from? Not saying that they are wrong, I just would like to find an online lens/angle calculator I can trust. I usually use the following:

http://www.sweeting.org/mark/lenses/cctv.php

Which says that 1/3" with 2.8mm would be 81º; I do think that it is more closer to 129º than 81º, I would love to see an online tool like the one linked above that I can know for sure is accurate

[Numb-nuts 1]

I have always found this calculator to be a good guide in real world situations.

It has calculated the closest size lens I need and taking account that only stock

sizes are available off the shelf I have had good result than by just guesswork.

 

Try it against some installation you have done and see if it calculated accurately.

I think you'll find it quite good.