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The reasons I will avoid 4k
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  • @markr041

    What about cameras that use all the pixels of the sensor - that oversample? Do they debayer from the full sensor (say 24 megapixels) and then downrez to 4K after debayering, in which case they are true 4K?

    It totally depends on the camera and its internal signal processing. Rule of thumb is that you get the best results if you debayer and downscale in post, because desktop software (like Resolve) can use much more computing-intensive, higher-quality algorithms than in-camera chips. Therefore the trend towards RAW video cameras. But a camera that has high-quality codecs and internal processing does the job as well - only that you then end up in league of the Canon C300, Sony FX9 etc., way above consumer and prosumer video and mirrorless cameras.

    According to Yedlin's test (linked further above), you even need medium format sensors to achieve true 4K...

  • @cantsin Thanks for the information. Unfortunately, because of a patent dispute, most of the "RAW" output is partially debayered in camera as I understand it - ProResRAW, BRAW, Z-RAW.

  • I found a solution that works. It is simple and obvious.

    If you own an old quad core computer like sandy bridge or ivy bridge i5/i7 with ou without overclock, it will be better to avoid shooting 4k 30p. If you shoot 4k 24p the playback in timeline will work fine without stutter.

    I did lots of cuts only / intercut with two different files and the playback worked fine with the native 4k 24p files. Less frames per second means less processor usage for decoding in playback.

    Avoid using 150mbps or 200mbps in camera and use 100mbps, this also helps. Use H264 compression in camera and avoid H265. Use 8bit recording and avoid 10bit and LOG. Avoid 422 and use 420 color. Avoid apply LUT. Use real time effects and grading.

    Set the program monitor window to 50% size and 1/2 (half) resolution.

    Close all other softwares.

    This way you do not need to transcode to cineform or to other intermediate codec and also do not need to use proxy files, you can use the native MP4 or MOV files for editing, and you will not need lots of expensive SSD storage.

    Another tip is to set the GPU refresh rate to the same frame rate of your footage, if you are working with 30p set the GPU refresh rate to 30hz, if you are working with 24p set the GPU refresh rate to 24hz. In my tests this helps for a better cpu usage in playback and also avoid stutter (not only the stutter from different frame/refresh combination, but it helps to avoid the stutter from real drop frames)

    If you work with FullHD 1080p you can shoot 30p no problem because the playback will be ok with native h264 files.

    Considering i5-2500k overclocked to 4,4ghz with 17,6ghz total can edit native 4k 24p h264 100mbps files so the minimum system for 4k 30p will be: i5-9600kf intel processor with 6 core overclocked to 5ghz with a total 30ghz, 4x4gb ddr4-266=16gb ram, asus prime z390M plus motherboars. This upgrade is not so much expensive and can solve the 4k 30p editing. Two layers of 4k 24p or 30p need a GPU with 768 cuda cores and 2gb ram.

    If you need to do chroma key with two layers or picture in picture or long wipe dissolve compositions you can keep working with 4k 24p and transcode to cineform 10bit and it will work fine in the old quad core computer using 50% size / half resolution preview.

  • @apefos I have edited many Multicam 4k 24p projects (h.264 100mbit original media) on a i7 3770k Ivy Bridge based HackIntosh, no overclock. Adding a RX580 8GB GPU helped over my old 1050 TI. But what helped the most was to make proxies in 720 h.264 and edit from those in Premiere Pro 2018. Then upon export premiere uses the original media to render. I usually had a 1080 24p project timeline and about half the projects had no reframing so I rendered a 4k version.

    I definitely agree that shooting in 4k and down rezing to 1080 creates a better 1080 image, and the flexibility of the extra rez helps in many areas.

    I hope you can find what suits your case (sounds like you have from your last post) and eventually can see what we are talking about. We are not all on the latest gear and newest computers either, but, I spent the time to master the options of what I do have, to make it work.

  • @apefos why don't you just use proxies in your NLE?

  • I am considering start working with proxy files, but...

    It is impossible to do chroma key with proxy files because the different compression and resolution do not allow to adjust the key with precision

    The color, shadow highlight corrections can be slightly different

    The motion and picture in picture movements can be slightly different

    Audio can work ok because the proxy files can have same audio properties

    Proxy are small and storage is not a problem

    So in some situati0ns proxy can work ok, but some situations intermediate codec can be better

    Intermediate codecs can hurt quality a little bit

    The great thing is to use the native files to preserve quality, save time, save storage, and simple workflow

  • After processing a few 4K Canon CLog (H.265) and Sony SLog3 (H.264) clips, I'll have to agree with you @apefos Absolute waste of time converting to ProRes/DNxHR, slowly working the rec709 luts and adjusting dynamic range, exporting to another 4K DNxHR, and finally converting to H.264 1080p for delivery.