I have set up some cameras and a cheap dvr so i'm not a complete noob, but i am not really clear on how the capture cards work. as i understand, there are ports with bnc connectors that plug into the card, is there also a video out on the card, or is the video out on the pc monitor using the zoneminder program? also, does 8-port mean 8 cameras can be input?
some of the cards i have seen pictures of show only 4 cables, but say 8 ports. any and all answers will be greatly appreciated - thanks
video capture card noob questions
8 ports 8 cameras yes
Ok lets take the simplest example.
A standard capture card for the tv it has inputs like ant. composite, svideo and when your watching and recoding tv you select the port its connected to and it records at 30 or 25 fps.
No with the cctv cards you don't need that high of a frame rate 10 is about as high as you ever need to go. Now on one of these cards you see has 4 inputs and 1 capture chip.
Now that capture chip can record at 30 fps just like the tv capture card. but for cctv we dont need 30 fps. So what the card does is it switches between all the inputs and grabs snapshots from each. Now as you can imaging this slows it down a little bit by having just 2 cameras connected your at 10 fps on each camera. So that 30 fps is effectively 20 now. now adding 4 cameras your fps per camera goes down to 3 so 12fps for the 30.
Note there are more expensive cards that do real time but its not needed most of the time 10fps is the max most of the time. So a 8 chip card can run 16 cameras at 10fps.
Ok lets take the simplest example.
A standard capture card for the tv it has inputs like ant. composite, svideo and when your watching and recoding tv you select the port its connected to and it records at 30 or 25 fps.
No with the cctv cards you don't need that high of a frame rate 10 is about as high as you ever need to go. Now on one of these cards you see has 4 inputs and 1 capture chip.
Now that capture chip can record at 30 fps just like the tv capture card. but for cctv we dont need 30 fps. So what the card does is it switches between all the inputs and grabs snapshots from each. Now as you can imaging this slows it down a little bit by having just 2 cameras connected your at 10 fps on each camera. So that 30 fps is effectively 20 now. now adding 4 cameras your fps per camera goes down to 3 so 12fps for the 30.
Note there are more expensive cards that do real time but its not needed most of the time 10fps is the max most of the time. So a 8 chip card can run 16 cameras at 10fps.
)