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Hi there,
I am shooting my footage with a Sony A7RII but usually keep the picture profile at normal. I really want to get into shooting Log footage but every time I try the final clip just looks washed out or the colors don't seem accurate anymore.
Whatever I do it just doesn't look right. I tried shooting overexposed by up to 2 stops, played around with curves in the Lumetri Color panel, tried several LUTs but the final result is always unusable. Sure, there are people customizing the S-Log profile even more but I think I should be able to output acceptable video without that extra step.
My videos aren't really bad but they would definitely benefit from a higher dynamic range.
Any idea what I might be doing wrong?
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You need to see somebody do it in a tutorial - like this one:
Grading Log Footage in Premiere Pro CC - YouTube
Go to 2:35 in to the start of the tutorial.
There are lots of others - do a Google search.
MtD
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That video alone was incredibly helpful. Thanks Meg!
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Personally, am shooting with a Sony A7s (the first version) and a Sony A6300. I've never found the S-Log feature that valuable for the work we do with it. Using the Canon look emulator Picture Profile ($$):
http://www.eoshd.com/pro-color/
MtD
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I imagine I'd feel the same with those cameras. I don't think log encoding is of any real use until you've got at least 10-bit media and 13+ stops dynamic range and high bit-rates. Then, it can encode more significantly closer to the limits of the sensor. Below any of those, I've not seen anyone really get notably better imagery.
Neil
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"... but the final result is always unusable."
It would be most useful for you to both tell us and show with a screen-grab your process and that final result.
But when you say final result, are you meaning looking at it within PrPro or after exporting in say ... the QuickTime player? If say on re-import it looks fine in PrPro, but that export doesn't look as "deep" in QT, well ... that's QT, not the media.
There are two separate parts to correcting a LOG encoded clip ... first, inverting the curve that was used in-camera to make this back to a "normal" or normalized clip ... for this, you need a curve adjustment that you can simply apply ZAP to nearly all clips from the camera.
Second, you need to adjust each clip's black/white points, shadows, mids & highlights, plus saturation ... the same as any other clip. But this must be done before that curve adjustment, through that curve in the scopes and display, or the inverted curve will possibly clip data that your camera worked pretty hard to record. This is all basic Log normalization as taught by Alexis Van Hurkman, and done daily in Avid, Resolve, Baselight, wherever. In Resolve, for instance (the most used grading app in professional suites), LUTs are always applied to the output processing side of a 'node' (layer, in Adobe terms) ... so you apply a corrective LUT to the first node, then go into the node and adjust the clip. The adjustments are processed before the LUT, and you see the clip in scopes & viewer after the LUT.
What's the starting point?
First, you need to have a good sense of when you've got a properly inverted curve shape for the Log. This is why a lot of people do like to start with the manufacturer's LOG corrective LUT for that camera. As one builds skills, most of the colorists I know end up creating their own corrective LUTs for the cameras they work with most often. I could add more detail about how to create your own if you want, but for now, just say ... if you shoot a standard medium contrast scene with a bit of real white and real black with that camera set in LOG, and when loading the uncorrected clip into PrPro, the top of the data in the Waveform scope is about 65-70 on the left-hand scale, you've got the exposure pretty close.
Now, at the top of the Lumetri tab, there's a little three-bar menu panel. You can save this Lumetri effect with only that curve set as a preset, saving it with the name of the camera it's built for, or save by choosing "Export .cube." Either works, you just apply them a bit different.
The second is the method I use.
Neil
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Thank you Neil for that in-depth tutorial. I'm going to shoot some footage later today and try out the steps you mentioned.
Do you shoot overexposed at all or would you recommend against it?
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No ... in fact, I got a small monitor for my video work so I could check focus when using my full-frame Nikon glass on a Panny GH3 M4/3 body via adapters. Yea, big help, right?
Well, it does do that pretty slick ... but most of the time it's in false color mode so I know exactly what's above 100, and what's at 90. I'm aware of the 0-10 area, but ... I guard the highlights. The real dark areas well ... they kinda mush anyway at times. Those proper sparkly bits, and gradated highs rather than harsh-lined clips ... those are mandatory.
Testing with a good video-designed tone ramp & color chart plus a good 'controlled lighting' shoot to then check for where the real exposure needs to be for best post work is so crucial to precisely repeatable work. Do this with different camera settings, all that sort of thing ... and test and compare in PrPro. May take up to 2-3 days the first camera you try to master.
But after that, with that camera ... you know what to do, and how to do it again. And have a very good idea how and when to modify because of shooting conditions.
If you're using a camera's LOG settings, if you want to make your own normalization LUT, it's a good idea to see where the top of the data of an non-normalized clip sits in their suggested workflow. Typically, it's between 65-70. I've seen one camera where if the top of the log came in over a low 60's number, you might have problems with whites. Just good to know, as that's how you figure out how set the camera. What keeps predictable whites before clipping.
Neil
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the only downside to lumetri is that you can't change the hue. you can actually make your own free lut inside photoshop.
grade inside photoshop convert video to smart object or just export one png frame, and go to filter-camera raw filter, then save preset as .xmp. then
download
after generating its lut table, take that png into photoshop, apply your .xmp preset in adobe camera raw and save-as a new filename.
then open iwltap lut creator(click its question box to select 64 cube) and select the new filename. it will create a brand new 64 cube lut.
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if you post an example image I can show you what I mean. you can make your own luts align perfectly with the the skin tone line, 3d rotate your colors, and even adjust the camera raw sensor data(rightmost button) so that you can get normally impossible colors that would normally clip or over saturate in lumetri and still look awesome.
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here's how to make a premiere lut from pure scopes in 60 seconds. my first video!
create scoped lut in 60 seconds - YouTube
steps:
1. set black point 0 IRE , white point 90 IRE, enable paint solid to find 41 IRE 18% grey for proper gamma exposure
2. hold ctrl+lumetri eyedropper to get skin tone, turn on mask
3. rotate hue to align to skin tone line
4. change white balance and center up HLS scope
5. increase saturation until 90% filled up YUV scope.
I've also attached the neat preset that I made that calculates 18% grey from an exclusion transfer solid to get exactly 41 IRE in rec 709 curve which is what premiere natively uses.
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I've never worked with Sony cameras, but when shooting LOG with the BMPCC, my first step in color work is to apply the BMD supplied LOG to Rec. 709 LUT.
My first recommendation would be to do the same here. Find a Sony developed LOG to Rec 709 LUT and start there.
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the problem with consumer luts is that they are only 32 cube(posterization) and the skin tones are wrong(magenta), and often clipping highlight rolloff. that's why there's like a million 3rd party lut providers.
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the problem with consumer luts
That's why I specifically said "Sony developed". As in made by Sony for their Log footage.