Viewing Angle of Camera [Archive]

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Joe Johnson

13-01-2005, 13:18

Does anyone have a spec or done an experiement to know the maximum viewing angle of the CMUcam2 (left/right viewing angle and up/down viewing angle)?

I looked but didn't find anything in the documentation. Sorry if I missed it.

Joe J.

Mike Betts

13-01-2005, 13:27

Joe,

As usual, you and I are heading down the same path. When the camera sights two vision tetras, the "center" of the combination will be tracked...

An interesting problem. N'est-ce pas?

CJO

13-01-2005, 13:36

I do not know the angle offhand, but it is possible to close down the window size to reduce the view area.

Joe Johnson

13-01-2005, 13:51

I do not know the angle offhand, but it is possible to close down the window size to reduce the view area.
While I know I must be heading someplace good if Betts is leading the way, in this case, I think he is out there blazing a path while I have not yet packed my bags.

My reason for asking was more along the lines of "How much of the field can I see?" rather than "How can I keep from seeing too much?"

In this case, software is no help. It can reduce my field of vision by ignoring pixels but it can't increase it by adding pixels to the side of a CCD array.

So... ...my question remains.

Anybody know and willing to tell us?

Joe J.

petek

13-01-2005, 22:06

techtiger1

13-01-2005, 22:20

I measured it tonight: about 60 degrees field of view.

Nice. Data you guys. I asked a simliar question before but it was about the actual range of the cmu2. How far can that camera see before the object it out of sight. I looled thru the manual but could not find anything on the distances. Thanks everyone.

Alan Anderson

14-01-2005, 09:37

Nice. Data you guys. I asked a simliar question before but it was about the actual range of the cmu2. How far can that camera see before the object it out of sight. I looled thru the manual but could not find anything on the distances. Thanks everyone.
It's a camera. It doesn't have a range limit. How far away it can detect something would depend on the size and brightness of what it's looking at. I am certain it would have no problems seeing an object nearly a hundred million miles distant, if that object were sufficiently large and well lit.

Joe Johnson

14-01-2005, 11:09

60 Degrees both in the UP/DOWN and LEFT/RIGHT direction?

Joe J.

petek

14-01-2005, 13:25

60 Degrees both in the UP/DOWN and LEFT/RIGHT direction?

Joe J.
I measured just left/right.

Al Skierkiewicz

14-01-2005, 13:44

60 Degrees both in the UP/DOWN and LEFT/RIGHT direction?

Joe J.

Joe,
The lens is listed as a 4.9 mm, F2.8 lens(I had to search but found it on one of the CMUII sites). The target area is 4.86 mm x 3.64 mm. for a diagonal of nearly 1/4", the listed specification for this device. Plug in the numbers for the diagonal and the focal length and it comes out to about 60 degrees. Since the aspect ratio for this camera is 4:3, the horizontal look angle is less than 60 degrees and the vertical is even smaller. This of course is in a perfect world and the lens in this camera is not self compensating for focus, distance to pickup, etc. so the FOV (field of view) will vary from camera to camera. According to my lens calculator (fudging for the tiny pickup area, my calc only goes down to 1/2") FOV (horizontal) is 22-25 ft. at 20 ft from the camera.

petek

14-01-2005, 14:11

Joe,
...According to my lens calculator (fudging for the tiny pickup area, my calc only goes down to 1/2") FOV (horizontal) is 22-25 ft. at 20 ft from the camera.

That correllates well with my measurement of about 9 ft (left:right) at a radius of 9 ft. If the aspect ratio is 4:3, then you should expect about 60 degrees horizontally x 45 degrees vertically. I wasn't trying to measure the FOV to high accuracy - figure 9 ft. +/- 3 in. - but somehow I doubt that FOV accuracy is going to be that critical a factor with these cameras...