Datapath x4 to Black Magic SDI box weirdness

Bro, does your rig even lift?
Post Reply
Digitrevx
Hasn't felt like this about software in a long time
Posts: 146
Joined: Sun Feb 21, 2016 18:16

Datapath x4 to Black Magic SDI box weirdness

Post by Digitrevx »

Hey, so I got a situation where I've got a Datapath x4 (DVI ver) having odd issues with 4 SDI runs.

Datapath
https://www.bhphotovideo.com/c/product/ ... html/specs

SDI conversion boxes
https://www.amazon.com/Blackmagic-Desig ... F7R9V5M9SY

I have 4 Single link DVI to HDMI cables going into each of these black magic boxes.

The odd issue is that at random I get flickering on one of the 4 projectors the runs are being sent to. If I swap that black magic box with Decimator and run it in interlace mode the problem run will start working..

Decimator
https://www.amazon.com/Decimator-MD-HX- ... P1JM4RCACY

So the question is why does this happen and why would running it in interlace fix it. Is it a bandwidth issue or a datapath issue??

I'm not sure if its a specific run issue if the flickering can happen on any of the runs every time I power cycle the datapath..

Online
Zoltán
Team Resolume
Posts: 7088
Joined: Thu Jan 09, 2014 13:08
Location: Székesfehérvár, Hungary

Re: Datapath x4 to Black Magic SDI box weirdness

Post by Zoltán »

How long are these SDI runs?
Software developer, Sound Engineer,
Control Your show with ”Enter” - multiple Resolume servers at once - SMPTE/MTC column launch
try for free: http://programs.palffyzoltan.hu

SAMOYO
Met Resolume in a bar the other day
Posts: 2
Joined: Fri Sep 13, 2019 16:03

Re: Datapath x4 to Black Magic SDI box weirdness

Post by SAMOYO »

Hey there - I have a similar issue at the moment - would love any immediate help.

Setup:

4k Display Port out of GPU to Datapath x4 -->
Datapath input set to 3840 x 2160 Quads -->
Output quads set to 1920 x1080P -->
HDMI out of Datapath -->
Plugged into Blackmagic Micro HDMI to SDI converters -->
SDI runs direct to projectors.

I see signal, it operates very fast(especially over 300ft runs).

Issue:
Periodically one of the project signals will drop, or blink for .5-3 seconds. This happens randomly, but also when faster or colorful content is played back...it is not consistent though.

I have looped out a HDMI signal from the converter to make sure sure it is not the distance / projector. Which I can confirm, the issue happens on the hdmi loop too.

Hypothesis:
It is the BM Converters, which are made more for broadcast and they do not like the 1080P signal going into them. They automatically convert the signal, so I do not have discrete control on how they are doing the conversion.

The Datapath x4(which I am new to) can not send out 1080i.

Possible Soltuon:
Change out the BM converters for Decimators to control the output signal discretely and make sure it is 1080p OUT running down the SDI cables.

I am not savy with SMPTE / broadcast / SDI signal per se, so I am shooting a little in the dark.

Any help would be super appreaicted.

Thank you community ~

Post Reply