HDMI 720p@50Hz inout not recognised

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willemdrijver

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  • Joined: Wed May 12, 2021 1:35 pm
  • Real Name: Willem Drijver

HDMI 720p@50Hz inout not recognised

PostWed May 12, 2021 1:43 pm

Hi Blackmagic forum,

I am a new user with a UltraStudio 4K Mini which I use for capturing video for YouTube publications on Retro devices like Commodore, Atari, Sinclair, etc.

One of these devices (an FPGA board) outputs HDMI in 720p at 50Hz.

This displays fine on all of my HDMI flatscreen monitors, but sadly a black input screen on my Blackmagic...

My ACER monitor tells me that it detects 1280x720 with H-Freq=37Khz and V-Freq=50Hz.

Using a (cheap Chinese) upscaler I can upscale the 720p to 1080p and that input is recognised.

But off-course I would like to capture directly without any upscaler in between.

Is there anything I could do to get my nice new UltraStudio 4K to accept the 720p input on HDMI?
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Xtreemtec

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  • Location: The Netherlands

Re: HDMI 720p@50Hz inout not recognised

PostWed May 12, 2021 6:59 pm

The capture devices of bmd often only support broadcast resolutions and framerates. Anything that is flagged different or is not up to spec will not be captured.
Daniel Wittenaar .:: Xtreemtec Media Productions ::. -= www.xtreemtec.nl =-
4K OBV Trailer, ATEM TVS HD, 4M/E Broadcast Studio 4K, Constelation 8K, Hyperdeck Studio 12G, Ursa Broadcast 4K, 4K fiber converters with Sony Control
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Howard Roll

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Re: HDMI 720p@50Hz inout not recognised

PostThu May 13, 2021 10:36 pm

willemdrijver wrote:My ACER monitor tells me that it detects 1280x720 with H-Freq=37Khz and V-Freq=50Hz.


Assuming 37 is rounded down from 37.5 those are the correct timings for plain old vanilla 720P50. It could be an RGB 8 bit 4:4:4 vs YCrCb 10 bit 4:2:2 issue but the US4k should be cool with either. More likely just basic incompatibility somewhere. Is 720P60 an option?

Sometimes an active split can stabilize the signal and there's always the option of converting to SDI, that process should cost only time and money, leaving the original pixels intact.

When the price of the Atari 1010 Cassette drive dropped to $200 dollars I forked out my own money to pimp my 1200XL. Cload, then a solid hour of raspberries, then (hopefully) Telengard.

Good Luck

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