NTSC and PAL are both standard definition, so on the one hand you might think in a MP/HD setup they wouldn't get in the way.
But I'm not sure thats true. Has anyone tried a PAL NVR w/ a NTSC HD monitor?
Subscriber Discussion
Does PAL/NTSC Matter Anymore When Using IP Cameras And HD Displays Via HDMI?
Brian Rhodes
Sep 16, 2016The analog PAL/NTSC spec is relevant to define cameras connecting to DVRs, but once that signal becomes digital (ie: HDMI) it is not a factor.
U
Undisclosed #1
Sep 16, 2016So you are confident that a NVR that is labeled as PAL (only) will work fine with a HD screen labeled NTSC (only) as long as the connection is via HDMI?
Edit: changed DVR to NVR
JM
John McNally
Sep 19, 2016It depends on the NVR and the monitor. If they both support HDMI, they should also support Extended Display Identification Data (EDID). EDID enables sources (the NVR) to discover the capabilities of sinks (the monitor). When the HDMI cable is connected, the monitor will let the NVR know it's capabilities, including the resolutions and frame rates that it supports. It will also let the source know its preferred (native) resolution and frame rate. If one of the resolutions and frames rates the monitor supports is the same as one of the resolutions and frame rates the NVR supports, the monitor will display the video. Otherwise the monitor may display some kind of error message such as "out of range" or "resolution not supported" or just not display anything.
The monitor stores its capability in an eeprom which is powered from the source when the HDMI cable is connected and so the monitor does not have to be switched on for the communication to take place.
The same mechanism has been used in PC's for many years.
U
Undisclosed #1
Sep 19, 2016Thanks John. Besides the issue of 25fps support, I understand that PAL and NTSC have different color spaces.
Is that also part of the EDID transaction, and if so, is the monitor likely to be able to adjust?
Also, side question: Since it appears that NVRs can be changed from PAL to NTSC using different firmware, why don't they just make it part of the config?
JM
John McNally
Sep 19, 2016They have different Primary Chromacities but according to the EIA_CEA-861 specification, which defines the CEA Extensions for EDID, both PAL and NTSC use the SMPTE 170M spec as the default color space.
There is probably a marketing reason why an NVR may only support one standard. In some cases the standard the NVR supports may depend on what type of camera is connected to it when it powers up or if it can be changed in the config, the NVR would have to be rebooted in order to support the new standard.
U
Undisclosed #1
Sep 19, 2016Thanks John, very informative. I'll report back when I try.
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