CinemaDNG files DARK!

skybandit · Feb 26, 2017

Searched the forum for this topic but didn't find it so...shot some CinemaDNG test footage and it's crazy dark. Normal or very not normal? Shooting ProRes looks great - no problems. The image looked perfectly normal on my iPad and played back looking normal (on the iPad through the DJI app). A single frame is pretty big so I'm attaching a screenshot of what I'm seeing.

But here's an update...while writing this post I opened the frame in Photoshop and it automatically opened up in the Camera Raw conversion window and looks good. So I'm guessing everything is fine and the files just look like complete crap when viewing in the Finder (on a Mac). So the question then is what is the best way (on a Mac) to process these files into a movie?

NickU · Feb 26, 2017

Download the trial version of DaVinci Resolve - should be able to handle them. If you need the 5K output, then you'll need to stump up for it.

Adobe Premiere, apparently, can handle them too but takes ages to process them.

skybandit · Feb 26, 2017

I'm going to tack on to this post and ask what the best way to expose for CinemaDNG is. In the previous screenshot you can see that outside the garage is totally blown out and basically unrecoverable. Did another quick test containing the highlights outside and the interior, as expected, is super dark. But when I bring into Photoshop I can bring the dark area into proper exposure (which is fantastic!). Did not judge for noise yet.

In any case, it appears the rule of thumb is "protect your highlights" but any tips for how to get ideal exposure in order to retain highlights but also minimize the amount you may have to pump up the darks in post? I have no idea where the "over exposure" zebras are set so don't know how far I can push that end of things - if that warning means totally gone or approaching gone but still retainable.

Feet Up · Feb 26, 2017

Hi Skybandit,

What editor are you using? I had this same question with Premier CC in Windows. Dark (with those magenta a highlights). There are a few ways around this. If you want to use Premiere (assuming that you are) you can use SlimRaw first (compressed but still DNG) or convert to an alternate format in After Effects. Alternately, you can use Davinci Resolve which will open and edit the RAW files with no intermediate steps.

skybandit · Feb 26, 2017

I'm using FCPX (not my favorite but I have an aversion to forced subscriptions). I just found a cool link explaining how to convert the DNG files through Resolve...

Convert Inspire 2 Raw Files & Grade D-Log - Mastering Drone Footage - PART 4 | cinema5D

Now if only I had time to learn how to actually use Resolve for more than just converting, I'd probably color with that. I've never liked the way FCPX handles color.

smoak5 · Feb 27, 2017

All dng files are like that. You need to decide it first. Resolves decodes it as well but is much faster than after effects.

Feet Up · Feb 27, 2017

Hi Bandit,

You likely have figured this out but the zebras and histogram are based on your SD Card Video settings. So set to LOG on your SD settings and Zebra will not show any blown highlights. Same is true of all of the styles. Each style changes your zebra results and your histogram. When shooting RAW I I have my SD settings at None and custom with -3 for all three options but this blocks the histogram from hitting its extremes (that seems bizarre to me) and affects the zebras as well. You need to be very mindful of the SD setting to use either Zebra or Histogram.

As far as Resolve for DNG, it is quite easy and does allow native RAW editing.

skybandit · Feb 27, 2017

Ah...I'm just getting in to this so hadn't noticed the SD settings affecting zebra and histogram but that makes complete sense. So CinemaDNG is only affected by your exposure settings but the SD style settings are essentially your viewing LUT? Is proxy footage recorded to the SD card while shooting CinemaDNG and ProRes? Easy enough to check, I know, but quicker to ask.

skybandit · Feb 27, 2017

Also...any advice on the best settings to use if you're going to color correct as well as best settings if baking in the look and no coloring in post? I plan on doing my own tests but would be good to know this now until I have a chance to go through it.

Feet Up · Feb 28, 2017

skybandit said:
Ah...I'm just getting in to this so hadn't noticed the SD settings affecting zebra and histogram but that makes complete sense. So CinemaDNG is only affected by your exposure settings but the SD style settings are essentially your viewing LUT? Is proxy footage recorded to the SD card while shooting CinemaDNG and ProRes? Easy enough to check, I know, but quicker to ask.

Hi Bandit,

Your SD settings are clearly impacting the histogram and Zebras. How accurately they are doing that in terms of what is being recorded to the SD card is less clear. In any event, it is not directly related to what is being recorded to the SSD. What DJI is using to generate the Zebras and the histogram distribution in DJI Go4 is also unclear. The files being recorded to the SSD are my priority so I am trying to best match the histogram and zebras to what I am recording to the SSD. If that is CinemaDNG, my assumption is that the "None" SD setting is likely best. I have been setting the style to custom and contrast, sharpening and Saturation all to -3. Zebras will kick in a bit later at these settings and the histogram will not reach its extremes (but values will stack up at the light and dark limits as you adjust exposure so you still have an idea of what is going on). I have it set this way so that I am not monitoring brightness from sharpening to the SD files that will not apply to the RAW files, etc. If you want to be very conservative about protecting highlights then possibly "None" with 0,0,0 would be fine. I found that this was leading to a bit darker exposures than I needed.

Feet Up · Feb 28, 2017

skybandit said:
Also...any advice on the best settings to use if you're going to color correct as well as best settings if baking in the look and no coloring in post? I plan on doing my own tests but would be good to know this now until I have a chance to go through it.

I just received my first SSD so I also am in testing mode. Here is a test I did for myself on a Cinema DNG 5.2K clip I shot a few days back. Possibly it will be useful to you as well. The file was not converted prior to import into Resolve. I dragged the RAW clip into the media pool, 3 point edit into timeline. Under color I changed the Decode setting to "Clip", the Color Space and Gamma to Blackmagic Design and I ticked highlight recovery. The 3 variations are 3D LUTS. The first is Blackmagic Design Rec 709, the second is Arri Alexa Rec 709 with a gamma push. The 3rd is one of the stock Resolve Kodak Rec 709 film looks with a gamma push. Straight to Deliver from there with no additional grading, etc. All could be spruced up a lot but this will give you an idea of what it would look like to use CinemaDNG to quickly slap clips together with minimal changes.

skybandit · Mar 1, 2017

Wow, that is a gorgeous scene. Pacific NW?

Today I shot a whole bunch of tests: color modes in CDNG, PR422, 4444XQ, H.264 and H.265 and resolution charts for all. Also did this on my i1 and Mavic. Here's what I've learned...

- CDNG not at all affected by color mode changes (Normal, D-Cinelike, etc.) - Feet Up you pretty much pointed that out in your earlier post.
- PR422 also not at all affected by color mode changes. This surprised me. Am I missing something??
- Perhaps not surprisingly, 4444XQ also not affected by color mode changes.
- The microSD card appears to record a colored proxy file for CDNG and PR422 but not for 4444XQ.
- FCPX and Resolve do not recognize H.265 - do we care?

That's all for now. I'm sure I'll have more to report after I spend more time with the footage.

Feet Up · Mar 2, 2017

Hi Bandit,

Yes, PNW.

Here is a related post about the 5R: X5R Footage looks dark

The Histogram and Zebras may be generated from the Lightbridge files...but, the setting from the SD card definitely has a user selectable impact on what the histogram and Zebras are based on. I am not finding any info on what % the Zebras are supposed to be based on. I also have not found anywhere to user select Zebra % so we are a bit left guessing there. I would guess 80% for Zebras. It would be great if we could select %.