4K to 1080P monitor

[Pepijn Klijs]

Hi,

I was wondering if anyone here knows what might caused my system to not properly display a 4K image on my SDI output.

I was working with Sony F55 RAW 4K footage. I set my project settings in Resolve to the source footage resolution, which was 4096 by 2160. I then set the monitoring resolution to 1080P, because I have an HD reference monitor connected via a Decklink SDI card. Normally, the image would be scaled to fit inside the 1080P signal so in this case scaled down, but for some strange reason the image wasn’t scaled at all, so I just saw a portion of the frame displayed full screen on my monitor.

Is there somewhere in my system a certain limitation towards downscaling or resolution? (I’m not using Lite version of resolve, but latest ‘payed’ version.) Could it be the Decklink SDI card? I do think my settings were ok, ’cause when I switched the project to 2048×858 (scope) resolution the images appeared as expected, downscaled to 1080 to fit on my monitor.

Any ideas?

Thanks,

Pepo

(other useful system info: mac osx 10.7.4, GTX 560 Ti 2GB and GTX 580 1,5GB.)

Editor/Colorist, Amsterdam, The Netherlands
http://www.pepijnklijs.nl

[Timo Teravainen]

Which Decklink card are you using?

More GPU ram could make a difference with 4K footage.. but I don’t know if it affects scaling like you described. For me, RED 4K footage scales to 1080 without any problems.

[Peter Chamberlain]

Set the timeline to HD, to match your monitor. This will help your speed while grading too. If you need to render at 4k, reset the timeline res prior to render.
Peter

[Pepijn Klijs]

Hello Peter and Timo,

Thanks for your help!

I found the issue thru some help on another forum. I completely forgot about the ‘output scaling presets’, which were on ‘match timeline’ in this case. I never had any trouble before, cause I hadn’t done any 4k or 2k work since a while. When I was working in 2K I did notice that the image was slightly cropped on the sides on my monitor which should be the difference between seeing 2048 in a 1920 frame vs. 2048 scaled down to fit a 1920 frame.

Thanks again,
Pepo

Editor/Colorist, Amsterdam, The Netherlands
http://www.pepijnklijs.nl