Generic ONVIF PTZ's

[jmulvihill]

I am looking at Ebay for a ONVIF IP PTZ 30X.
I've had great luck using standard PTZ's on EBAY with an encoder. Just wondering if I can expect the same with IP.
I'm looking to use BlueIris for my Video Management System.
Any feedback?

 

[badmop]

Forgive me, but what do you mean an "encoder" I'm curious if it's what I'm thinking, I could be interested in that myself.

I've looked for 30x PTZ and there aren't as many 30x as there are 20x and less usually. I currently have a 36x SD PTZ and I wouldn't want anything less than 30x myself.

 

[bp2008]

The difference between 20x and 30x is not as big as you might think. Just take the fully-zoomed-out horizontal field of view which you can find in most spec pages, and divide it by the magnification number to calculate the actual field of view you would get.

For example lets assume you have a PTZ that starts with a 60 degree field of view. If you zoom to 10x, you get 60 / 10 = 6 degrees FOV. Zoom to 20x and you get 60 / 20 = 3 degrees. Zoom to 30x and you get 60 / 30 = 2 degrees. So you only gain half as much zoom going from 20x to 30x as you did going from 10x to 20x.

I guess what I'm getting at is that if you could spend the same money and get a 20x 2 megapixel PTZ or a 36x analog PTZ (standard definition) then you would be better off with the 20x 2MP hands down.

 

[jmulvihill]

Encoder takes a standard CCTV camera with a BNC connector and converts it to IP.
AXIS M7001 for example.