Log and RAW workflows

What is in this article?:

RAW — Uncompressed

The left path presented in Figure 2 shows the 2.5K 12-bit CMOS sensor feeding logic that wraps the serial-RGB raw signal as CinemaDNG data. Captures are made at 23.98p, 24p, 25p, 29.97p and 30p. These uncompressed 12-bit data are recorded to an SSD.

Several applications can handle RAW footage. These include: DiVinci Resolve (from Blackmagic); Speedgrade for Premiere CS6; and Adobe After Effect’s (AE) RAW importer. I used After Effects for this article.

After launching AE, go to Preferences and choose Import>Sequence Footage. Set the Frame Rate appropriately. Click OK.

RAW select file
RAW white balance exposure control
RAW white balance custom
RAW S-curve applied
New composition command
FCP X import dialog box

Now set the Files>Project Settings. Set Depth to “16bpc” which defines the project to have RGB channels with each channel utilizing 16-bits. Click OK.

Then, issue the Files>Import File… command. (See Figure 6.) Now browse to a folder of DNG frames. Select the lowest number frame and confirm Format is Camera Raw. Also, confirm Camera Raw Sequence is checked. Click Open to import the clip and auto-open the Camera RAW window. The frame will be deBayered to create an RGB image.

On page 12, Figure 7 shows the control panel with white balance controls that are by default set to “As Shot.” This footage, courtesy Marco Solorio (©2012, OneRiver Media), looks perfect — too perfect for use in a noir production. Figure 8 shows the scene with the Custom color temperature dialed down to 2700 degrees.

Next, a slight S-curve is applied to deepen shadows and add punch to the highlights. This is done with another panel. (See Figure 9.) When finished grading the RAW frame, click OK to make all frames in a clip share the same settings. This type of adjustment is called a “one-light” grade.

Next, issue the Composition>New Composition command. Set Preset to “Custom” and dial in 2432px and 1366px. Now, set the Frame Rate to 23.976 and click OK. (See Figure 10.)
Double click the clip so you can see it in the Viewer. Issue the Composition>Add to Render Queue command. Set the Output Module to “Custom: ProRes 4444.” Doing so defines a conversion of 12-bit RAW frames using floating path math to 16-bit values that are exported as ProRes with 4:4:4 color sampling. Lastly, render the composition. It will take some time to deBayer each frame.

Now launch your NLE. Figure 11 shows the import dialog box for FCP X. By creating a proxy (ProRes) file at import, editing will be done using this performance-oriented file.

During export, ProRes 4444 source files are written to disk. (Effects and composites must, of course, be decompressed — from ProRes 4444 — to RGB floating point. These segments will be compressed to ProRes 4444 during export.)

While pre-processing RAW isn’t difficult, it is very time consuming. Working with log ProRes is far faster because the deBayering is done in-camera rather than in software on a computer.


Steve Mullen is the owner of DVC. He can be reached via his website at http://home.mindspring.com/~d-v-c.

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