Blackmagic Forum

I've been told by a reliable source that the Constellation HD and 4k have a 3-4 frame delay due to the frame converters on the inputs.

Even if all the sources are the same frame rate, the converters can't be turned off and cause the delay.

I have a 2 M/E 4k without the frame converters and it's one frame of delay, so virtually not noticeable for IMAG scenarios.

Can someone from Blackmagic confirm this or anyone that's done real testing?

Thanks!

Bump @Admin

I’d expect that if you want Blackmagic to rescind the advertised less than 10 lines of latency you’ll need something more subtantial than the heresay provided by some guy.

Good Luck

Howard Roll wrote:I’d expect that if you want Blackmagic to rescind the advertised less than 10 lines of latency you’ll need something more subtantial than the heresay provided by some guy.

Good Luck

I'm not asking them to rescind anything. Can you provide a link to the ATEM 2 M/E 4K and ATEM 2M/E 4K Constellation latency specs? I'm trying to find them and verify them in order to make a business decision because I occasionally do IMAG in the same spaces with speakers and latency can be an issue.

Best,

David

The Processing Delay is listed in the tech specs section of the Products page. For most of the Constellations it’s <10 lines.

https://www.blackmagicdesign.com/produc ... s/W-APS-41

Good Luck

Because there were some changes in this area recently on the Constellations, I wanted to verify the processing delay. As Howard posted, the specification is less than 10 lines. I verified this on the Constellation models today. To achieve the input to output latency of the ATEMs, the SDI signal must be locked to the same reference as the ATEM (or to the ATEM itself). The signal must also be advanced by the amount of the processing which is 10 lines. All of our studio type cameras have this line timing. I like to set it to -15 just to make sure it's ahead of the ATEM. So lock the camera reference to Program or Input video from the ATEM. Set the line timing to -15. And the SDI out of the camera will be 15 (or so) lines later on the ATEM. Very simple actually. Please note this applies to any video path through the ATEM that doesn't involve scaling or rate conversion. The DVE and Supersource willl add a frame. If you don't match the ATEM Resolution or frame rate, there will be possibly a few more frames of delay. Keep it all the same if possible. Any other latencies you will notice will be caused by displays and any other processing the video might pass through. Also, because this comes up often, the Videohub and SDI distribution do not have "any" latency. When I say "any" you might find a few nanoseconds about using expensive test gear. I hope this helps.

Gary