PTZ Domes: control protocols and programming

[jets 0]

Greetings: I've been installing non-PTZ cams for over a year. Now I need to learn about PTZ domes. Client currently has an older Videolarm motorized heated dome housing, with a Honeywell mini box cam- wide dynamic, day/ nite, 1/3"CCD, 3.8-11mm lens. This setup uses a problematic coiled connection cable that I replaced once. All the unit does, and all the client wants it to do, is pan back and forth 24/7 between 2 manually adjustable stops. Cam composite video output goes directly to DVR. Noone monitors cams or operates the PTZ function. Time for a current model unit with no dangling coiled cable. So far what I've heard is that most PTZ domes need to be programmed via a controller or DVR that has PTZ control features, and that an RS-485 connection needs to be made between controller and dome.. I also was told that most PTZ units utilize 1/4"CCD's, not 1/3". This cam pans a ground level parking garage.. the current varifocal lens produces adequate image. There is currently no control cable run to any camera locations. I'd like to get an outdoor PTZ dome (temps reach below 0'F). What are the programming options? Is there a PTZ dome I can program via laptop once its in place, using RJ45 IP or 9pin serial or usb connection or something? What are the different remote control and programming protocols in use currently? Can any PTZ dome be connected to any DVR- control wise? i.e. if DVR has RS485 connection, will it control any PTZ dome that uses 485? Or do I need to consider proprietary protocols? Is 1/4" CCD the standard for PTZ domes? If so, why? Why not 1/3". Suggestions for decent (not extravagant) units? The bottom line is: What is the most practical replacement for the old videolarm housing/ camera setup?, and is the a PTZ dome that can be programmed at the camera location without needing to invest ina separate controller? Any info is greatly appreciated. Thanks.

[Soundy 1]

Disclaimer: the following advice will apply to MOST common professional-grade PTZ cameras. It may or may not apply to cheap consumer or offshore no-name units.

 

Is there a PTZ dome I can program via laptop once its in place, using RJ45 IP or 9pin serial or usb connection or something?

You can use a USB-to-RS232 serial adapter, readily available for cheap, to connect a laptop to the camera, set up your autoscan, and then leave it run. As in the disclaimer, this may depend on the particular camera's autoscan capability. You'll need some appropriate software as well; I regularly use one called PTZ Controller, available from www.serialporttool.com

 

What are the different remote control and programming protocols in use currently?

There are too many to name, as most manufacturers have their own proprietary protocols. However, most (almost all) professional cameras support Pelco D and/or P protocols, as do the vast majority of controllers, software, and PTZ-capable DVRs.

 

Can any PTZ dome be connected to any DVR- control wise? i.e. if DVR has RS485 connection, will it control any PTZ dome that uses 485?

I wouldn't say "ANY" but the vast majority will work. Some DVRs will have RS-232 instead of RS-485, in the form of a standard DB9 male connector; this can be wired directly to most cameras that support RS-485 and will work just fine over shorter runs.

 

Is 1/4" CCD the standard for PTZ domes? If so, why? Why not 1/3".

For the exact WHY you'd probably have to ask the designers, but some possible reasons:

- PTZs are more expensive overall, so using 1/4" sensors keeps costs down a bit.

- A smaller sensor allows a smaller camera and a smaller lens with a greater overall zoom factor.

- A smaller assembly allows for a more compact camera.

- A smaller assembly is also lighter, which allows the camera to be more responsive while using cheaper, more efficient motors.

 

There are 1/3" PTZs, like the Pelco Esprit, but those are generally a similar design to what you have now - a standard housing with a box camera inside (although they don't use the troublesome coiled cable). These also tend to be SUBSTANTIALLY more expensive than their smaller dome counterparts, as they have larger cameras, heavier housings, and thus require more powerful motors.

 

Suggestions for decent (not extravagant) units? The bottom line is: What is the most practical replacement for the old videolarm housing/ camera setup?, and is the a PTZ dome that can be programmed at the camera location without needing to invest ina separate controller?

Try finding a used Pelco Spectra II or Spectra III, or perhaps a Capture FasTrax II. These are solid cameras that I've used, and they work fine with Pelco D/P protocols. If you want something smaller, look for a Capture MiniTrax.

 

One other thought: if your DVR supports it, and depending on the area to be covered, consider a 3MP or larger IP camera with a wide-angle lens, or something in a multi-lens panoramic camera (see Capture OmniScape or various Arecont offerings). Then you don't have to worry about something happening in one area while the camera is pointed somewhere else... you just record the whole area, all the time, and zoom in later.

[jets 0]

Disclaimer: the following advice will apply to MOST common professional-grade PTZ cameras. It may or may not apply to cheap consumer or offshore no-name units.

 

Is there a PTZ dome I can program via laptop once its in place, using RJ45 IP or 9pin serial or usb connection or something?

You can use a USB-to-RS232 serial adapter, readily available for cheap, to connect a laptop to the camera, set up your autoscan, and then leave it run. As in the disclaimer, this may depend on the particular camera's autoscan capability. You'll need some appropriate software as well; I regularly use one called PTZ Controller, available from http://www.serialporttool.com

 

What are the different remote control and programming protocols in use currently?

There are too many to name, as most manufacturers have their own proprietary protocols. However, most (almost all) professional cameras support Pelco D and/or P protocols, as do the vast majority of controllers, software, and PTZ-capable DVRs.

 

Can any PTZ dome be connected to any DVR- control wise? i.e. if DVR has RS485 connection, will it control any PTZ dome that uses 485?

I wouldn't say "ANY" but the vast majority will work. Some DVRs will have RS-232 instead of RS-485, in the form of a standard DB9 male connector; this can be wired directly to most cameras that support RS-485 and will work just fine over shorter runs.

Learning here: afaik, RS232, in its most basic form, utilizes PINS 2, 3 & 5 for Transmit, Receive and GRound respectively. afaik, 485 uses 2 wires, often labeled A + B. Are you saying that, for short runs, between and rs232 and rs485 device, wire connection can be made between rs232 pins 2&3 and rs485 pins A&B? If so, does 2 go to A and 3 go to B?

 

Is 1/4" CCD the standard for PTZ domes? If so, why? Why not 1/3".

For the exact WHY you'd probably have to ask the designers, but some possible reasons:

- PTZs are more expensive overall, so using 1/4" sensors keeps costs down a bit.

- A smaller sensor allows a smaller camera and a smaller lens with a greater overall zoom factor.

- A smaller assembly allows for a more compact camera.

- A smaller assembly is also lighter, which allows the camera to be more responsive while using cheaper, more efficient motors.

 

There are 1/3" PTZs, like the Pelco Esprit, but those are generally a similar design to what you have now - a standard housing with a box camera inside (although they don't use the troublesome coiled cable). These also tend to be SUBSTANTIALLY more expensive than their smaller dome counterparts, as they have larger cameras, heavier housings, and thus require more powerful motors.

 

Suggestions for decent (not extravagant) units? The bottom line is: What is the most practical replacement for the old videolarm housing/ camera setup?, and is the a PTZ dome that can be programmed at the camera location without needing to invest ina separate controller?

Try finding a used Pelco Spectra II or Spectra III, or perhaps a Capture FasTrax II. These are solid cameras that I've used, and they work fine with Pelco D/P protocols. If you want something smaller, look for a Capture MiniTrax.

 

One other thought: if your DVR supports it, and depending on the area to be covered, consider a 3MP or larger IP camera with a wide-angle lens, or something in a multi-lens panoramic camera (see Capture OmniScape or various Arecont offerings). Then you don't have to worry about something happening in one area while the camera is pointed somewhere else... you just record the whole area, all the time, and zoom in later.

 

Thanks again for info.

[Soundy 1]

Learning here: afaik, RS232, in its most basic form, utilizes PINS 2, 3 & 5 for Transmit, Receive and GRound respectively. afaik, 485 uses 2 wires, often labeled A + B. Are you saying that, for short runs, between and rs232 and rs485 device, wire connection can be made between rs232 pins 2&3 and rs485 pins A&B? If so, does 2 go to A and 3 go to B?

 

RS485 typically has terminals labelled RX(A) and RX(B) for receive, TX(A) and (B) for transmit... in the case of the camera, you only need to receive, so they may simply be marked A and B. Some also mark them as RX+/RX-.

 

On the RS232 serial port side, you're only sending, not receiving... so you'll only use pins 2 and 5. I find it USUALLY works to connect pin 5 to RX(A) and pin 2 to RX(B), but the odd time you need to reverse it, and sometimes you need to power up the camera with it connected one way, then hot-swap the wires. But those tend to be the rare cases and I've mostly seen it with older cameras.