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eGPU for video processing on a laptop – Does it make sense?

I needed a portable solution that could also serve as my video editing station so I had to decide if a quad core with a dGPU is that important in my workflow. I did a small test with proxy generation in FCPX across MBP 15", MBP 13" & MB 12". It was with 3 XAVC-S 4K files with a total of 10min duration, located on an external USB3 hard drive: MBP 15" 2.7 455 2016        ~ 3.5 min MBP 13" 3.3 2016              ~ 4.5 min MB 12" m7 2016               ~ 15.5 min I knew the 12" throttled but after the test I realized how much it can affect performance. I was very impressed with the performance of the 13", it was much closer to the 15” than expected for a supposedly CPU heavy task.  The 13” would be a problem for Resolve though because it lacks a dGPU, but the eGPU solution looked promising so I got an AKiTiO Node to try with my GTX titan & the MacBook 13 3.3 2016 . It was a breeze to set up with instructions from this very useful forum:
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Lightroom & Skin tones

Many of you will call me crazy, but I got spoiled from the colors (especially the skintones) that I can get from my A7rii in video with the custom profiles. Still profiles in camera just do not have the same customization level as in the video. Even crazier was the fact that I could not get the stills to look as good with Lightroom, unless I spent a significant amount of time fine tuning all different color settings for each picture. While Lightroom offers plenty of controls to mess with color, it still does not give you the full control like 3D LUTs do (check this to see what I mean). Lightroom has some default camera profiles that you can use but none of them really look that good. For example with the A7rii the default Adobe Standard looks washed out and the Camera portrait has Sony's renowned green-yellow skin tones. Then I found out about the  DNG profile editor , which acts like an LUT editor for stills. It is quite straight forward to create your own custom profile: Ex

Skin tones with Premiere/FCPX/Resolve

If you thought that adjusting simple things such as exposure, contrast or playing with curves would really behave in similar manner across different NLEs, well guess again. I always thought that yellowish-greenish dark skin tones & magenta bright skin tones were (yet) another Sony quirk. Interestingly the image out of the camera was fine but as soon as I made a change in the Lumetri panel, skin would turn into this deadly color.  So while I was about to create an LUT to fix them I tested Resolve and FCPX and lo and behold I could not reproduce these awful tones! What’s the deal then? After testing extensively these programs I found out that all three behave differently! Resolve: gain changes all three channels with the same multiplicative factor. While that creates nice desaturated shadows, skin highlights have a problem since the red channel clips first and then green follows creating these yellowish hues. FCPX: exposure is just an additive term on all three channels, so wh

rec709 LUTs - Fuji color profiles

I did some quick reverse engineering of some of the Fuji profiles and created rec709 LUTs that can achieve similar results. No Fuji camera necessary and no need to shoot with a baked-in profile! Here is an example applied to a clip from A7rII: Long story short took advantage of the fact that Lightroom allows color profiles to be used with RAW files. Then I computed the three-dimensional affine transformation that can remap the default color space from adobe to any of the Fuji psrofiles. I can do a much better job if I find color samples that span most of the 3D space. For this I used 4 sample images from dpreview and imaging resource. The good thing is that I can use the program that I wrote to compute any transformation that is needed. For example S-log/s-gammut to rec709, or slog to clog, rec709Sony to rec709Fuji etc... I only need two images from the two profiles with the same color information such as a colorchecker and of course neutral WB and same exposure.  You can fi

A7Rii + M43/Cmount lenses with crop/zoom

Had a couple of m4/3 & c-mount lenses that I decided to test with the A7Rii and its zoom function. Lets first see how the quality of the zoom mode compares to the FF and S35 modes. Test done with FE 55 f/1.8 at 12800 ISO recorded in 4K 100mb/s.   For FF, S35, S35 x1.5 & S35 x2 the fov was matched in camera. The S35 150% & S35 200% were shot at x1.5 & x2 distances respectively and cropped in Premiere. Quality is best with S35 as expected. S35+1.5X and S35 with 150% crop are very close to FF. It appears that the zoom mode works by cropping the S35 and upscaling again to 4K. Then I tested the SLRMagic 25mm and I was delighted to find that it was usable even with X1.1 zoom. A c-mount lens that I had was usable with X1.4 zoom. I was surprised by that since spec wise it was designed for a 2/3" sensor. I really liked the hexagonal blur plus it focuses at 10cm! So there you go folks. If you have the A7rii and any manual m4/3 or c-mount lenses go and buy these che

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