zach

Thanks, Soundy. I think you're basically saying that I can kiss shallow depth of field goodbye and should probably just go with a "webcam style" IP camera. I was confused because CS are 16mm size lenses, while I believe 16mm is equivalent to a 2/3 sensor, not the 1/3 I see on the best cctv cameras. I thought maybe they had some type of built-in adapter. That said, do you have any inexpensive recommendations? The look of the camera itself does not matter.

Hi All, I'm in the market for a PTZ camera to use for a film shoot and am hoping to get answers to a few (possibly dumb) questions. From looking around, I get the sense that there are two broad categories of cctv cameras. Some (mostly newer models) look like webcams and are often wireless. Others are larger anc take CS lenses. I think I would prefer the latter, as it seems they would have superior image quality (hopefully like an SD camcorder from a few years back?), plus depth of field. However, it seems that those ones require some type of separate mount for the PT part of PTZ and I am having some trouble finding these. Also, I am wondering if either type has limitations on the degree they will pan and tilt. My guess is that they use servos and therefore only have 180 degrees of motion. Anyway, I could use any recommendations for a PTZ camera that would create the most cinematic images possible. I would prefer one that uses the Pelco protocol so I can hack together some custom software to control it. I was thinking something like this: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330370542468&ssPageName=STRK:MEWAX:IT. Thanks, Zach

Well, for example the following webcam style ptz cameras from eBay do not have full 360 degree panning: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220502010606&ssPageName=STRK:MEWAX:IT http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=320427466338&ssPageName=STRK:MEWAX:IT and this small mount does not either: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=110297425100&ssPageName=STRK:MEWAX:IT These may not be "traditional" ptz cameras, but they seem to be in abundance at the lower end of the price range. Also, I think you may be wrong about depth of field. It is a function of the ratio of focal length to aperture. Consumer level camcorders, for example, generally have sensors that are two small to achieve a shallow depth of field. This is why people use adapters to put 35mm lenses on their camcorders. Basically, I highly doubt any of the ptz cameras with a fixed lens would allow shallow depth of field, but I was hoping the ones that take CS lenses would, since those are basically the same as 16mm film lenses. But now the question is, are there any CS lenses that allow software controlled zoom and focus?

I'm looking to get something quite inexpensive and was hoping to save by buying older used equipment on eBay. Hd isn't necessary and latency doesn't matter. Ideally, I'd like it to be closer to an SD camcorder than a webcam. I am correct in thinking that the models that take CS lenses will give me depth of field as opposed to fixed lens cameras, correct? Like the difference between a camcorder lens and 16mm film lenses? Are you sure about that model I linked to not allowing software to control zoom and focus? I thought that's why there's a cable going from the lens to body, although that could be just for built-in autofocus. And I doubt that all ptz cameras have 360 degree rotation, as I think many I looked at were 180. By 360 do you mean it can do a full rotation and then reverse, or that it can essentially spin in a circle through several full rotations? Btw, what difference does the dome make? Is it basically like having a wide angle adapter?

Hi All, I'm new to the forum and to CCTV, so please bear with me. I am wondering if any CCTV cameras accept MIDI input. I am also interested in track systems that would allow for remotely controlled movement like a dolly system in film. Any information on these would be greatly appreciated. Many thanks, Zach

Ah, I looked on wikipedia and apparently all digital CCTV cameras contain hardware that encodes the video so that it can be transmitted over an IP network. Because the technology is immature, there is no standard codec used. Rather, current models use anything from MJPEG to H.264. In Max applications I have experienced a loss in framerate while recording quicktime movies and doing pretty much anything else. On the other hand, I see no downside to using a dvr, which I can tell to start and stop recording with Pelco, and exporting the video to my computer later. This probably takes up a little more resources than running dedicated control and recording software written in C, but can anyone speak to even that?

Well that's what I'm asking. What format does CCTV video use? Would I be able to record high quality video through Firewire or USB without significantly slowing down my computer? From my experience, the answer has been no and I've found it's best to have any necessary conversion done in hardware.

Wow, Pelco actually seems pretty easy now. As far as recording, I'm assuming I would need a capture card and considering I have a laptop that would be quite expensive (although I may get a desktop soon). I also think this could slow down my computer. Would it be best to just get a dvr and send that Pelco messages as well? Finally, back to my track discussion. Can you link me to some ptz broadcast cameras that run on tracks? I wouldn't know what to search for and just want to compare prices.

Survtech, that may sound funny, but I would be thrilled to be able to do even that. I looked into Pelco a bit. Looks like I'd have to write a wrapper in C in order to control it in Max or anything high-level like that. As I'm not that great a coder, I think my best bet is to find some readymade control software that I can in turn control with Max. Do you know of any cheap or free Pelco control software for Mac that accepts serial or tcp/ip input? It seems this would be available for situations in which the CCTV setup was hooked to a computer locally, but needed to be controlled remotely over a network. The Mac thing, I'm not sure about though...

Thanks, Soundy. The reason I asked about MIDI was because I was hoping I could write my own software to control the cameras and that is an easy protocol to work with (also the basis for MAX/MSP, the language I do most of my AV work in). If it does not make sense to talk to the cameras directly, perhaps I can control the CCTV software through tcp/ip. Since I'm a total noob to CCTV, I should probably do some research before asking more questions. Can you point me to a document that describes the protocols used in CCTV networks as well as software options and camera compatibility? Since you mentioned it, I should also read up on computer-controlled broadcast cameras, although they are probably outside of my price range. If you can point me to any references on these that would be great as well. Thanks again, Zach