Why isn't there a standard bullet camera in 2.8mm lense?
- Thread starter blake
- Start date
Securame
Pulling my weight
I think there has never been. 2CD20xx have only been made 4mm and up, there has not been a 2.8mm version.
You might want to crak one open and change the lens yourself, but you will probably find out that you are either unable to focus the camera, or that you get a "tunnel" effect (you will get the corners of the image black).
You might want to crak one open and change the lens yourself, but you will probably find out that you are either unable to focus the camera, or that you get a "tunnel" effect (you will get the corners of the image black).
Securame
Pulling my weight
Yes, you said it, varifocal. The casing on the 2CD26xx is way bigger than the casing on a 2CD20xx, and the lens is completely different.
Securame
Pulling my weight
Probably because of the space between the sensor and the glass of the camera. Pics of the unassembled camera here:
http://www.cctvforum.com/viewtopic.php?f=19&t=37006
You could try to change the lens on a 2CD20xx youself for a 2.8mm lens. Might it work? It sure might work. But as I said, you might be unable to focus the lens (it will hit the IR cut filter before it is in focus) or you might get a tunnel effect. I would be surprised that noone has tried it before.
On that thread you will see someone did change the 4mm lens for 6mm, 8mm and 12mm.
Quotes:
"The 1 / 2.5” format ensures that the lens introduces no dark corners in the image, and that the distortion is also lower because the lenses are using the most central part."
"The dimensions are very similar to the original lens of HIKVISION which will help to not collide with the front glass of the camera."
http://www.cctvforum.com/viewtopic.php?f=19&t=37006
You could try to change the lens on a 2CD20xx youself for a 2.8mm lens. Might it work? It sure might work. But as I said, you might be unable to focus the lens (it will hit the IR cut filter before it is in focus) or you might get a tunnel effect. I would be surprised that noone has tried it before.
On that thread you will see someone did change the 4mm lens for 6mm, 8mm and 12mm.
Quotes:
"The 1 / 2.5” format ensures that the lens introduces no dark corners in the image, and that the distortion is also lower because the lenses are using the most central part."
"The dimensions are very similar to the original lens of HIKVISION which will help to not collide with the front glass of the camera."
CamFan
Getting the hang of it
To get wide angle, you need a larger front flat glass, which increases the body diameter of the bullet.
In my measurements, Hikvisions 2.8mm lenses are really more like 3.2 - 3.25mm, so even the domes don't give you the wide angle they advertise. Nor are the actual angles correct.
https://www.ipcamtalk.com/showthread.php/2759-Hikvision-focal-length-angle-of-view-and-other-lies
In my measurements, Hikvisions 2.8mm lenses are really more like 3.2 - 3.25mm, so even the domes don't give you the wide angle they advertise. Nor are the actual angles correct.
https://www.ipcamtalk.com/showthread.php/2759-Hikvision-focal-length-angle-of-view-and-other-lies
