Datapath FX4 and FX4-SDI Delay and Lag

[Warspite]

Hi everyone!
Sorry for creating this new topic, maybe later it will better to stitch all info about datapath in one topic.
But now i do not have a lot of time to decide Datapath FX4 purchase, so fast answer is very welcome.
We plan to buy both FX4 and FX4-sdi versions. There is no information on how much delay adds Datapath.
And because we plan to route not only prerendered content, but also live feed from cameras through Arena and Datapath it is very important to know how much will be delay from Datapath.
Is this this delay stable or it depends on mapping inside Datapath hardware?

Many Thanks for your experiments!

[cvanhoose]

I received 30ms for every 60fps output on the x4 models.

[Warspite]

30 ms is very nice!
But it is for X4 not FX4 or for FX4-SDI/
This new models have genlock, so we can hope for even lower latency!

1 frame delay for 25 fps PAL camera input is already 40 ms. So 30ms is just 1 frame, when i used to see around 4 frames for hardware scalers from Blackmagic and Datavideo (well some advertise 2 frame, but for selected types of conversion). Need to measure Decimator latency.

Thanks for reply!

[Warspite]

From Datapath support (fast reply, wow):

1 frame latency between input and outputs if genlocked.
Up to 2 frames latency if free run (not genlocked)

Regarding scaling and cropping, these have no impact on the latency.

I found this latency extremely low for the task Datapath is doing and considering that this 1 or 2 frames latency is at 60fps.

[Warspite]

Got a pair of Datapath FX4.
LOVE this piece of hardware!
Delay is as promised by tech support - two frames.
Display port is main input. If main input is lost - Datapath automatically switches to HDMI. Almost perfect hot backup solution for multiple output mapping events!
Works even weird combination - 4k on Display port from big Rack PC, and only 1080p backup signal from Macbook. Just needed to adjust mapping inside Resolume on Macbook, no need to adjust Datapath!
Got some problem with HDCP on Macbook - some led receiving cards from LINSN are not compatible (NovaStar works great). No problem with PC Rack - everything is working.
I know that there is a workaround for HDCP issues inside Datapath software, just need some free time to figure it out.
Problems with HDCP=red screen. So if you see red screen - disable somehow HDCP.

[Oaktown]

From the Fx4 user guide:

If an input source is connected to the Fx4 but the actual signal fails, the Fx4 will try to connect to a valid signal by scanning the input connectors in the following order: 1 - DisplayPort 2 - HDMI 1 3 - HDMI 2

If no signal is detected on either of the three input connectors the Fx4 will display a pre-configured Datapath logo.

To upload your preferred logo (max 4k), click on the Upload Logo button in the Devices Tab and browse to upload your logo.

[Warspite]

Regarding HDCP problem: i missed one step, so could not find right checkbox in software.
Everything is great now