In this episode of the podcast I ramble on about what a bummer it is that RED never released a Log to Rec709 LUT.

If you skip any Wandering DP Podcast this is probably the one to miss.


The Arri LUT Generator

The basic Arri LUT that I talk about in this episode is now standard inside of DaVinci Resolve but if you are looking to take the edge of the knee or shoulder you can create your own here:

LUT Generator

Only problem with creating your own is you are bound to run into the same issues as I did with RED projects.  THe chances of the post house or person finishing your project having your same LUT is slim to none.

Stick with the standard unless you are a high roller.*

*If you are a high roller send some tips my way. 

9 Responses

  1. Nathan Balli

    I find when grading from redlog film the noise floor is lifted across the spectrum any advice other than denoise? Is this more of a exposure problem?

    • Wandering DP

      It depends on what you are talking about.

      What do you mean when you say the noise floor is lifted? Is that before you put a LUT on it?
      If so then yes that is what is supposed to happen. The whole image should look very washed out and have little contrast. That is how the camera is packing in all the stops of DR.

      If there is noise after applying a normalizing LUT then yes it is your fault and probably down to ISO exposure issues.

      You don’t really ever grade uncorrected LOG footage. You correct it with a viewing LUT then grade it to get the most info possible.

      Hope that helps

  2. Greg Greenhaw

    I’m confused about your premise that you can’t recreate red gamma 4 in resolve. Its an option in the raw settings. Are you assuming editorial is receiving some sort of proxy clip instead of the 6k raw files?

    The biggest problem I see with red users is that the starve the sensor for light in dark scenes because they don’t have to foresight to expose a bit brighter to optimize the data in the sensor.

    On a side note, since the blue channel is the least sensitive and tends to have the most noise, What is your opinion of using cooler lights vs warm light to optimize the blue channel?

    • Wandering DP

      Hi Greg,

      I am aware that REDgamma4 is an option inside Resolve but that is not what I am talking about in the podcast.
      There is no LUT produced by RED to transform REDlog Film to REDgamma4. That is the issue. In my mind a major issue for RED.

      You would never grade footage inside of Resolve in REDgamma4. Never.
      This is where the confusion I am talking about gets started. Someone not very versed in the Post process or unfamiliar with how the sensor operates would see that REDgamma4 setting, see that it matches what editorial saw, and decide to grade from that.

      With the Alexa not so much. The post pipeline is very well understood. There may be a few factors involved as to why there is less confusion with Alexa stuff but here is my best guess.
      1. More expensive camera = Less chance of non-pros tinkering with it.
      2. Less options = Not as many dead ends to go down
      3. Arri provided a LogC to REC 709 LUT specifically for the camera = no brainer

      One fun thing to do is to vimeo search for Arri Alexa then vimeo search for RED Epic. The difference in the results make for some very interesting discussions. I will give you a hint: the amount of crap looking stuff loaded up by RED users is enormous. But it is just as capable of a camera (if not more so) than an Alexa.

      To understand why you would not want to grade in REDgamma4 as opposed to REDlog film would be a whole podcast but here is the best way I can explain it.
      REDgamma4 takes all the DR and color info and crams it into a tiny predetermined little box. If you want to move or isolate a certain bit of that info it is very hard to do because it is all crammed inside that little box.
      REDlog Film is easier to grade and looks nicer because all of the values are in their proper place and have not been crammed into a little box.

      There is a lot more to it than that but just don’t ever grade using RedGamma anything. You will be much happier with the results.

    • Wandering DP

      As for the blue sensitivity thing.

      The MX was definitely prone to Blue channel issues but I haven’t found the Dragon to be lacking when using Tungsten.

      As you said, the main thing is to understand the camera settings, how to get the cleanest image, and what you can do to maximize the DR by exposing properly. Very few people know the correct process.

      • greg greenhaw

        So are you saying if you lit a scene with 3200k with say a arri L7 then switched the color tempt o 5600k and compared the blue channels it would have about the same level of noise?

        As far as the redgamma thing. I agree you don’t want to grade in red gamma4. However with resolve 12’s new color managed workflow I believe they map the r3d data into their own color space so although you may start with a contrasty image in redgamma4 I don’t believe its lossy the same as it was in the past so you don’t clip out and DR.

      • Wandering DP

        What I was saying is that yes the blue channel is still the weakest on the RED Dragon (along with every other CMOS sensor camera) but it is nowhere near the issue it was with the M or MX.

        There were never issues with REDgamma4 in Resolve it is just a viewing format. Even in Resolve 11 you aren’t losing or gaining any info you are just remapping it and when you remap it before you grade it the challenge becomes locating specific values and isolating them.

        RED wanted people on set to be able to get a vague idea of what they were capturing in a color space similar to what they are use to seeing. REDlog Film was developed specifically to be the easiest and most flexible format for the DI.

  3. Drazen Stader

    So basically what you are suggesting to red dragon users is the following:

    1. shoot Dragon Color 2 + Red gamma 4 to get a punchy preview look and see the most contrast the image can get.

    2. When in color grading…start the grading from red log and build the look from there.

    3. Apply LUTs if necessary but only after starting with the red log.

    I love very much the arri warm skin tones and I am always trying to replicate those in post. Do you have a go to LUT when you are grading in resolve to start from and apply it to red log? If yes which one are you using?

    Great show!

  4. Ryan Emanuel

    I am down for the revolution! Sorry I’m late to the game. Thank you for this podcast, its an affirmation that I needed. I have been fighting this same fight that you describe and I was starting to doubt myself because so many production companies do it the wrong way. I recreated my own red gamma 4 thats pretty identical to red’s so I can keep the correct order of operations in resolve. I’ve found that its just a 1d transformation, not a 3d like the arri 709 lut is so its easy to reproduce. My footage has become so much cleaner and crisper, but I would say over half my clients grade straight off of the rmd data still.