multicam with SLog LUTs

Get answers to your questions about color grading, editing and finishing with DaVinci Resolve.
  • Author
  • Message
Offline

Leonardo Levy

  • Posts: 229
  • Joined: Wed Feb 19, 2020 7:45 am
  • Location: San Francisco Bay Area
  • Real Name: Leonardo Levy

multicam with SLog LUTs

PostSat Oct 23, 2021 8:16 pm

I'm about to shoot a multicam music promo in UHD 3-6 cameras (probably 3 cameras but 2 runs of each song). I'd like to shoot it in S-Log but am wondering if running S log with a LUT added in post will significantly slow me down or require a more compressed level of proxy. I'll be shooting on Sony FX9 and A7siii's and converting to ProRes 422 in post . I like to see my effects and color work while I'm editing and had surprisingly good luck with that on a 6 Cam previous piece but that wasn't S log. Its a promo not just a concert so I anticipate more effects and maybe some animated titles.
Last time I was in Res v16 but will upgrade to current version for this.
Also any advice on the best way to make proxies in 17.

Thanks Lenny Levy
2017 27" 5K Retina iMac, 4,2Ghz i7, 64G Memory, Radeon Pro 580 8GB,
secondary screen is 27" Apple Thunderbolt Display, 1T internal SSD
Offline
User avatar

shebbe

  • Posts: 124
  • Joined: Tue Mar 06, 2018 11:48 am
  • Location: Amsterdam
  • Real Name: Shebanjah Klaasen

Re: multicam with SLog LUTs

PostSat Oct 23, 2021 11:25 pm

I'm not too familiar with proxy workflow but for shooting / editing I'd highly recommend shooting in S Gamut Cine - S Log 3 for all cameras. This will give much more available dynamic range than an already converted signal in camera so if you are slightly under or over exposed theres not much to worry about.

For editing you can use DaVinci Color Managed setup set in SDR and flag all your clips as Sgamutcine/slog3.
(select them all and rightclick -> input colorspace) They'll all be auto converted to your output colorspace set in the project and no need to add LUTs anywhere.

If you prefer to use LUTs however it shouldn't be too taxing at all to have one across your entire edit.

I don't recommend converting your FX9 footage. If you have a decent system Resolve should be pretty fast decoding the mxf files so no need for extra compression. If the A7sIII mp4s are sluggish you could do those though.

Or if you mean creating proxies in prores instead of converting then yes do all and make that prores proxy in 1920x1080 :)
Workstation: ASUS PRIME X299-A / i9 7960X 16c/32t / 64GB DDR4 / 2x EVGA GTX1080Ti / 2x M.2 512GB & 1TB
Online
User avatar

Marc Wielage

  • Posts: 7791
  • Joined: Fri Oct 18, 2013 2:46 am
  • Location: Hollywood, USA

Re: multicam with SLog LUTs

PostSat Oct 23, 2021 11:47 pm

You can also apply SGamut3Cine and SLog3 with a CST node. I find this is more flexible than color management, because inevitably there will be other kinds of clips that pop into the project.
marc wielage, csi • VP/color & workflow • chroma | hollywood
Offline

Leonardo Levy

  • Posts: 229
  • Joined: Wed Feb 19, 2020 7:45 am
  • Location: San Francisco Bay Area
  • Real Name: Leonardo Levy

Re: multicam with SLog LUTs

PostSun Oct 24, 2021 12:34 am

Thanks that's very helpful, I've only used LUT's in the past and have never tried using either Color Space Transform or Davinci Color Management and frankly know nothing about them or even whether they are the same thing . I'm mainly a DP so tend to only get involved in Resolve when I have a project. Any suggestions for a good explanation/ tutorial for these and any thoughts about pros and cons, in a multicam using proxies?

I've used Optimized Media in the past in v16 but gather that the proxy workflow in 17 is superior. Does it matter whether I convert my A7s footage to UHD Prores first and then make proxies or just make the proxies directly from mp4's. My system is described below. Its adequate but far from new.

Lenny
2017 27" 5K Retina iMac, 4,2Ghz i7, 64G Memory, Radeon Pro 580 8GB,
secondary screen is 27" Apple Thunderbolt Display, 1T internal SSD
Offline
User avatar

shebbe

  • Posts: 124
  • Joined: Tue Mar 06, 2018 11:48 am
  • Location: Amsterdam
  • Real Name: Shebanjah Klaasen

Re: multicam with SLog LUTs

PostSun Oct 24, 2021 9:56 pm

Marc is right that it is more flexible to use a CST node instead.
Don't know any tutorials on it but in short the Color Space Transfrom is somewhat the same as a conversion lut but it's based on the math itself instead of a look up table that has a certain resolution to it. So it's a lot cleaner in that regard.
DaVinci Colormanaged is roughly the same but it makes the settings projectwide and "invisible" on the Edit/Color page to keep it clean and editable globally. It's much more streamlined that way but it also has some limitations/quirks for advanced users.

In terms of converting any color space like a log camera space to display space like rec.709 the CST will use the DaVinci DRT by default which is Blackmagic's flavor of how colors should appear in given display space so to speak. This creates a unified rendering intent that makes it easier to match different cameras compared to using conversion LUTs designed by the manufacturers themselves or third parties, having a different flavor each depending on what they think is best for their camera and taste. That's generally why this is a more preferred way of working.

In the Color Page as the last node place the ColorSpaceTransform effect and set the settings.
0.png
0.png (65.62 KiB) Viewed 104 times

You can do this per clip in the colorpage or perhaps create a group of all the slog clips and place it as post group node but i'm not sure how multicam works in Resolve in terms of creating new cuts/edits and maybe you'll add other footage too later.
Therefore I think it's also quite efficient to place it on an Adjustment Clip instead in the Edit page, given the fact that all your footage will be in the same space anyway. And if it's not you could place the ones that aren't above that layer.
This way the conversion is totally separated from your clips and you can edit and change all you want.
For efficiency you can lock that video track so you can't accidentally select, move or cut that layer.
Workstation: ASUS PRIME X299-A / i9 7960X 16c/32t / 64GB DDR4 / 2x EVGA GTX1080Ti / 2x M.2 512GB & 1TB
Offline
User avatar

shebbe

  • Posts: 124
  • Joined: Tue Mar 06, 2018 11:48 am
  • Location: Amsterdam
  • Real Name: Shebanjah Klaasen

Re: multicam with SLog LUTs

PostSun Oct 24, 2021 10:04 pm

Leonardo Levy wrote:I've used Optimized Media in the past in v16 but gather that the proxy workflow in 17 is superior. Does it matter whether I convert my A7s footage to UHD Prores first and then make proxies or just make the proxies directly from mp4's. My system is described below. Its adequate but far from new.
Lenny

I would just directly create proxies from all your footage and use your original files for final rendering and any colorgrading you might want to do. You'll need the proxy speed anyway for the editing speed. A high quality intermediate is not that necessary if you ask me.

One last thing I'd like to mention I think is still the same with A7sIII is that the camera doesn't handle card names and resets clipnames on every new card. So clip 1 will be C0001.mp4 but the second card first clip too. We usually for safety rename those files before we start using them and simply add something like "A7S01_" "A7S02_" as card prefixes to distinguish them. On a Mac this is very easy by selecting all clips and rightclick rename times then add prefix.
Workstation: ASUS PRIME X299-A / i9 7960X 16c/32t / 64GB DDR4 / 2x EVGA GTX1080Ti / 2x M.2 512GB & 1TB
Offline

Leonardo Levy

  • Posts: 229
  • Joined: Wed Feb 19, 2020 7:45 am
  • Location: San Francisco Bay Area
  • Real Name: Leonardo Levy

Re: multicam with SLog LUTs

PostMon Oct 25, 2021 6:18 am

Wow , Very helpful indeed. That all seems to be pretty clear and makes sense, at least as much as it can without having the edit in front of me. I really appreciate the help.

lenny
2017 27" 5K Retina iMac, 4,2Ghz i7, 64G Memory, Radeon Pro 580 8GB,
secondary screen is 27" Apple Thunderbolt Display, 1T internal SSD

Return to DaVinci Resolve

Who is online

Users browsing this forum: Google [Bot], Google Feedfetcher, jfykeaucq871, Marc Wielage, Nick2021, panos_mts, xunile and 56 guests