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A story about 4K XAVC-S, Premiere and transcoding

My laptop was not very happy that I got the A7rII. So there my quest for the smoothest 4K editing begun. First, I tried transcoding, but as you will see further down it did not give me the results that I was expecting, I could not match the quality of the original. Low res proxies would not cut it since I use warp stabilizer before I start editing. “Fkit, I ll make the machine of my dreams” I said. But no luck. This buttery smooth experience that I had with 1080p was impossible to reproduce with 4K XAVC-S. Solution? 4K proxies.
All tests below were done with an E5-1680v3 @4.5, 64GB EEC RAM, TITAN X, Revo 350 among other irrelevant hardware with Premiere CC 2015 and Windows 10. Hard to build something faster for Premiere (https://www.pugetsystems.com/labs/articles/Adobe-Premiere-Pro-CC-Multi-Core-Performance-698/. A single XAVC-S 4K 24p file was used. to render all the files with “Max Quality”, “Render at maximum depth”, “Use maximum render quality” with the Adobe media encoder cc 2015. Only for Prores HQ the RockyMountains Converter (ffmpeg) was used. For the playback test, playback resolution was set to full. Lumetri color with LUT and various other adjustments plus some sharpening were used as effects. 



A lot to interpret from these data but 2 are the main points:
1. For editing optimized codecs, you don't need many cores. A fast quad core should be enough.
2. Lowering the playback resolution makes your GPU happy. Removing the effects does that too, but usually you need to preview them more than you need the extra resolution.



As you can see there are very few transcoded files come close to the quality/colors/exposure of the original XAVC-S! I did not expect the banding issues with the Prores.
Conclusions for 4K XAVC-S, Premiere CC and Windows users:
1.       Don’t try to optimize your computer to edit 4K XAVC-S natively. Use proxies and low playback resolution if you want a smooth experience.
2.       For maximum output quality avoid using the transcoded files for the final render. If needed, use CineformYUV10bit. 

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