No difference between Presets

To learn the program and what settings to use I have rendered a 10 seconds 4K clip with different Presets: Medium, Slow, Slower and Very Slow. The resulting file show no difference in size or bitrate. When comparing them in FFMetrics there is no significant difference either. Every Preset renders in 29 seconds.

With Medium preset the settings looks like this:

crf=17.000 noise_reduction=8 opencl=1 preset=medium rc=crf x264-params=chroma-qp-offset=-2:aq-mode=3:aq-strength=0.800:rc-lookahead=110:keyint=480:min-keyint=3:bframes=11:b-adapt=2:ref=3:deblock=0:direct=auto:no-weightb=0:me=umh:merange=32:subme=10:psy-rd=0.77:no-chroma-me=1:trellis=2:no-fast-pskip=1

I have Voukoder 13.4.1 and FFmpeg seems to be 7.1.
I use Vegas Pro 21.
I am happy to pay for Voukoder Pro if I succeed in getting good results with it.

Do I have to uninstall the free version first?

I can´t make Voukoder Pro work. It seems that I downloaded this in January this year but never tested it then.

So the 14 day limited trial license key has expired.

I was now able to make a "scene" in the Designer and save it, but Voukoder Pro didn´t show up in Vegas.

Is it possible to get a new trial of the program?

Yes thank you. Now I see Voukoder Pro in Vegas.

But I can´t get Voukoder render to a mp.4-file. It´s just *.voukoderpro extension which won´t do anything. Vegas hangs each time. I have tested both with and without "Override filename" in Output properties.

I got it to work in the end.

The encoder I choose in the Encoder Properties is Intel H264, which doesn´t have any Preset with Medium, Slow, Slower etc.

I can see that Nvidia H264 has those options but I don´t have a Nvidia GPU at the moment.

So I think I´ll stick with the old Voukoder for now.

Thankyou for all your help.

I will try FFmpeg GPL.

In your FFMetric result it seems that very slow has the least good result and Medium has best in two respects.

I thought that slower rendering time would produce better quality.