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Grading Blackmagic DNG footage using Lightroom 4


I saw a post over on Philip Bloom’s site describing a workflow for grading the Blackmagic Camera’s footage in Photoshop, so I immediately wanted to start playing with the sample footage to see what I could do with it.

All the footage in my video can be downloaded from the Blackmagic Forum. They graciously offered the Raw files up for everyone to play with, and I jumped at the chance.

I’ve been using Lightroom since it first came out and think it’s THE best tool in my photography workflow. The ease and speed at which you can dramatically change the look and feel of an image, then copy that look to several other images in your library makes it an incredible tool for panoramas and time lapse videos. Add on the fact that you can export an entire group of images into a specific format in about 3 clicks and you’ll see why I thought it would be an amazing tool for working with the Raw images from the Blackmagic Cinema Camera.

I’ll preface this by saying I was really experimenting just to see if I could do this using the tools I already know how to use. I realize Blackmagic’s own Davinci software is setup to do this without as many steps, but I already know Lightroom and wanted to see how much I could push the image in the same way I do Raw photos from my Canon. Let’s jump in…

Step 1:

If you haven’t already downloaded the footage, you can get them from the Blackmagic Forum post that unveiled them. I also highly recommend reading over that entire post, since it explains a lot about how the camera works.

Step 1.5: Unzip the files (duh)


Step 2:
In each folder will be dozens of Raw DNG still images, each with a filename that indicates the frame # (I’m hoping the name is something you can set in camera, because having a specific name + frame # will be amazing for post production). It looks like every single 2.5k frame will be 4.76MB on disk. If my math is right, that means you should be able to fit just over 55,000 uncompressed frames on a 256GB SSD, which equates to about 38 minutes. This is not a lot. If you’re like me and you’re used to keeping hours and hours of video on a 32GB SD card on your DSLR, this will take some getting used to.

The good news is, you can set the camera to record in ProRes at 1920×1080. This is a very good compressed format, but it’s still compressed and as such doesn’t give you as much data to tweak. It’s also only 1920×1080, and part of the beauty of the Raw files is the extra bit of resolution you get.

Step 3:
“Import” the frames into Lightroom. In this case, in the import module I just told Lightroom to “Add” them to my catalog (this is usually the default behavior when importing photos that are already on your local disk anyway).

Now that they’re in your library, you have a frame by frame view of the entire video right inside Lightroom. This makes it incredibly easy to see every frame at a glance in a way that you can’t in any video editor. Of course you’re not going to apply a different treatment to every frame, but I can see this being useful for doing touch-ups here and there or doing rotoscoping.

Step 4:
The real benefit is the power of the Raw processing. Everything you’d expect in a Raw photo from your DSLR is available (with the one exception being the Camera profile, since DNG files have embedded profiles). I increased the clarity & vibrance, added sharpening and noise reduction and added a subtle amount of Split Toning to make her face a little warmer. If you’d like, you can import my exact settings by downloading this preset (right click->Save As): BM Grade.lrtemplate

Step 5:
From here, all you have to do is go to Settings -> Copy Settings (Ctrl+Shift+C), then select the rest of the frames (Ctrl+A) and go to Settings -> Paste Settings (Ctrl+Shift+V).

In 3 keystrokes, you’ve just applied the grade from one frame to every other frame in the filmstrip. Now you can use the scroll wheel on your mouse or arrows keys on the keyboard to scroll through the images to make sure everything looks good throughout the shot.

Step 6:
This is the part that took some experimenting. As of right now, Premiere doesn’t know what to do with the DNG files. That’s really OK for me, since you want to export the photos with the develop settings applied anyway. I wanted to keep the image as high quality as possible, so I exported everything to a TIFF file. Here are the specific settings I used:

I specified the 1920 width so that I could import directly into a 1920x1080p sequence in Premiere without having to scale. I trust Lightroom to give me the highest quality downsample possible, plus this should make editing a lot faster and easier since you’re dealing with a little less data.

Step 7:
Another part that took some testing. I know from the Forum Post that they shot in 24P. This is an important distinction…When your footage is cut up into a thousand still images, there seems to be no way to tell what frame rate you shot at. Since the camera can shoot 23.98p, 24p, 25p, 29.97p, & 30p, you will need to keep track of this. I haven’t played with the camera of course, so there could be a way to name the files or set the metadata in such a way that it records this, but in the test files that were provided there was no indication of the FPS either in the filename or the file properties. If the file could be set to something like “Title-3m27s-1of24” that would be a lot more helpful to me than just “frame000###”.

Now that we know it’s 24P and the files are 1920×1080, how do we setup the sequence? I supposed you could set everything manually, but I found the “Arri 1080p 24” preset worked just fine. Now you just import the TIFF sequence into your project. I find the easiest way to do this is to grab the folder, then drag & drop it into the Bin.

Step 8:

Now that you have the images in your project (Don’t put them on the timeline yet!), you need to set the duration. The default still image duration is 150 frames (~5 seconds), so if you haven’t changed this from the default, when you drag the images into the sequence you’ll have frames that last 5 seconds. If you got ahead of yourself and did this already, don’t panic. You can select all the images in the sequence, right click and choose “Speed/Duration”, then type “.01” into the Duration, check the “Ripple Edit” box and everything will be fine.

If you’re going to be doing this a lot, I suggest going into the preferences and just setting the default Still Image Duration to 1 frame:


Otherwise, you can select all the images in the Bin and set the duration just like you can in the sequence.


Final Sequence in Premiere

Step 9:
And there you have it! The TIFF image sequence can be played back just like any regular video and can be exported for the world to see. For this test I didn’t try to do any editing, so I just put all 5 test shots next to each other on the timeline. If you wanted to edit or use any fades, I’d probably make each shot into it’s own sequence and then edit using nested sequences, but that can get pretty taxing on even the most powerful computers.

I hope to get my hands on one of these cameras in the next month or two for a music video I’m shooting. If I do I’ll definitely be making a follow-up post since I know I’ll need to make some tweaks to this workflow. Like I said above, I’m sure Davinci makes this a lot easier, but I wanted to see just how close I could get to a Raw photo workflow and still output a high quality video. In the end, this is a very exciting camera for me. The amount of visual data you can capture in a handheld rig is impressive to say the least. The fact that I can use standard SSD drives and the Canon L glass I already own is just the icing on the cake.

  • robin Cawthorne

    Hi

    Check out robin cawthorne at Vimeo.

    I am putting together some videos showing grading workflow on mac and pc. I use lightroom and elements 11. Elements seems to be the only editor that allows the dng’s to be dropped straight to the timeline. Please let me know what you think.On my vimeo page or at robin@one-red.co.uk