Chroma Key- Hue-Chroma-Intensity render 30x length of video

Hi there, I was getting poor results when trying to do some green screen. I am afraid the lighting in my stduio is variable and I know I need to improve it. I was getting poor results using Red-Green-Blue as my Color Space but when I switched to Hue-Chroma-Intentisity the results were dramatically different, it was brilliant.

I also got very excited but then I discovered that the render time to a You Tube definiition was taking forever. Even at 50% frame size and 50% frame rate, I quickest I could get was over 30 minutes render time for a 1 minute video clip. Playing it back in preview was so jumpy it was not watchable. If I switched back to Red-Green-Blue it was fine but the results were poor.

Is this what I should expect? Can you offer any suggestions? I am about to start making a lot of training and tutorial videos but with a render speed of 30x it is not going to be easy.

The machine is a reasonable spec and hardware acceleration was ticked.

Thnak you very much, shall I post the specs of the PC? Which parts of it would help?

Yes, you should post the spec of the PC, and also if you have a high ram that doesn’t mean it will render faster, You need to have a good CPU or GPU to render faster, what ram does is that it just gives the power that the app needs to render.

I have no idea what you mean by 50% frame size, 50% frame rate. Can you explain this?

If the green-screen equipment you are using is not good enough you can create a “digital green-screen” of yourself using OBS and ZOOM - both free software. ZOOM can remove the background when you are using it and OBS can record the ZOOM session. You don’t actually have to be calling anyone on the ZOOM session, just displaying yourself on a digitally-created green screen background for OBS to record. You can even use it if you have some footage already with a less than perfect background. See here:

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Thank you so much. I have been using Zoom for months anyway but the quality wasn’t as good so I switched back to OBS.

When I Exported the video in You Tube format it ground to a halt until I went into the settings and reduced the output size of the video from 1920x1080 to 960x540 and the frame rate to 30 instead of 60.

Spec of PC
Intel i5-4570 @3.2-ghz
16GB Ram
NVIDIA GeForce GTX driving a widescreen and a standard size monitor
Intel HFD Graphics 4600 (onboard graphic) driving the 3rd monitor
Windows 10
USB Mic, USB Camera

Am I right in thinking that Red-Green-Blue uses a lot less CPU power to render than Hue-Chroma-Intentisity ?

Did you change the Video Mode, or the Advanced section of Export.

Advanced section of Export

OK so this is curious. I have the project open and is playing back much more like normal, a little jittery but certainly watchable. Out of curiosity I did the export again to a different filename and it is now estimating 8 minutes for the export and this is at full You Tube resolution.

I could be wrong but I do not think I have closed any other programs since yesterday but maybe there was something else competing for the CPU?