Monday, September 29, 2014

Color Grading your BMPCC footage

If you use the Blackmagic Pocket Cinema Camera to film your interview, you should be aware that you are committing yourself to an extra step in the filmmaking process. That step is called "color correction." This is because the footage from the BMPCC comes out "flat" looking - on purpose. It has been designed to be adjusted to your tastes afterward in the computer. This probably sounds very intimidating, and if you were to use some of the methods employed by professional film studios, it would be far beyond the skill set of both you and your instructor. Happily, the Documentary and Oral History Studio has purchased a copy of a program called "FilmConvert," which makes the color correction process much easier.

A BMPCC still frame before color correction with FilmConvert
After the application of color correction
In reality, having the color correction process built into what we call your "workflow" isn't a bad thing for students to experience. Color correcting will allow you to enhance the way your footage looks before you even begin to edit your film and it offers you an opportunity to correct any problems with exposure and color. It also gives you an enormous amount of control over the look of your film.

FilmConvert is a comparatively simple program to use, and if you are accustomed to adjusting the look of digital photos in something as simple as a social media style image filter like Instagram, you are already familiar with the concept if not the particulars. (Caveat - if you really know color science, you will be able to get even more out of the software. But luckily, FilmConvert may also be used more simply.)

The footage on the BMPCC is flat looking because it contains a bunch of image data that you will need to either enhance or subdue during the color correction process. One way we measure a digital sensor's quality is by its dynamic range, meaning it records more information. Likewise, the video codec - or format of recording the file - is important because the better codecs will be less "lossy" - in other words, they preserve as much of the sensor's dynamic range as possible when recording. Most cameras compress the signal in some way for the sake of data size and write speed, but the problem with compression is that you usually lose some of this dynamic range from the image taken by the camera. The BMPCC preserves a lot of the original image data using the ProRes422(HQ) setting - it's the payoff for the giant files and one of the main reasons people use this sometimes quirky camera. The BMPCC preserves even more when recording in RAW, but for the sake of practicality we aren't using this setting. Perhaps at some point in the future I will write a tutorial on how to use RAW, but it requires an exponential increase in computer processing power and hard drive / SD card storage space. In other words, we don't have the infrastructure, and it would be overkill for your current use in any event.

If you have imported your BMPCC footage from the SD card to a folder on your Buffalo Drive, then you are ready to start working with FilmConvert.

Since you are going to be using the Studio's iMac to run FilmConvert, look for the FilmConvert logo in the computer's toolbar at the bottom of the screen. The logo looks like this:

Use Film Convert 64bit

The program works in three basic steps: 1) Selecting your clips to color correct 2) apply your color correction settings and 3) rendering.

Step 1: Selecting your clips.

Step 1: Choosing the clips you want to color correct
You will notice in the above window that FilmConvert presents you with three main panels. On the left is a straightforward browser pane that allows you to find the folder into which you imported your SD card data. Go ahead and find the files you recorded. Clicking on a file places a thumbnail of that file in the center window with some additional recording information such as length, etc. To select the files that you want to color correct, drag these files from the center pane over to the right hand pane called "SHOT LIST."

When everything you want to color correct is in the right hand panel, click on TAB 2 "Film Settings" at the top.

A tour around the "Film Settings" window - Step 2
Step 2: Color Correcting your Footage

You will notice that you have a lot of different settings to choose from in this pane. This is where your artistry will take place. By the numbers:

1) This is your shot list. You can select one clip or work on multiple clips simultaneously. The clips being used will have the small black box with a white asterisk in the corner. Tip: Only correct multiple clips at the same time if they are multiple shots of the same interview. I.e, the same exact scene and subject.

2) Scrub through your scene to find a representative frame to base your color correction choices upon.

3) Very important! Make sure FilmConvert has the proper camera preset selected. Here it is set for a Canon 1D. Select the Black Magic Pocket, and make sure emulation is set to "Film," which is what we are recording with. This will all of a sudden make a giant difference in the way your file looks because FilmConvert has a bunch of color science built in behind the scenes to make a particular camera's footage look like a particular type of film stock.

4) Exposure and Temperature settings. As a novice color grader, you are much more likely to use the exposure slider than the color temperature slider. Exposure is just that. If your shot is too dark or too light, you can adjust the whole thing here. But there are other places you can adjust just parts of your exposure. See below in "8."

5) Film Presets. This is one of the coolest features of FilmConvert. Here you can select the type of film stock that you want your footage to emulate. Try them out and see what you like. See what looks most natural to you.

6) Within the Film Presets there are some "global" adjustments you can make to color and curve. Plus you need to set the target film frame size. If you aren't sure what to do here, use Super35.

7) Film Grain setting. As far as grain is concerned, I find the standard 100 to be too much. I usually reduce grain to about 20 to 35. To me this seems enough to take that "videocamera" look away without getting too grainy.

8) Three-way color correction. Be careful, but these are powerful tools if used right. The dot in the center of the color wheel adjusts color balance in the shadows, midtones, and highlights. You can also use this to adjust exposure in those three zones.

Notice how selecting the right camera immediately changes the color correction of the footage to look more appropriate.
Notice in the lower left hand corner of the screen you will find presets. You can use your own or use some examples provided by FilmConvert. I have not found any of these presets provided by FilmConvert to be useful. BUT, you will probably want to create YOUR own preset once you have adjusted the image the way that you like it. Notice at the top of the adjustment panel on the right is a button that says "SAVE AS PRESET." It's that easy. To use that preset, just call up the next clip and double-click on the preset. You might not use the preset as-is, but instead use it as a basis point for making fine-tune adjustments but otherwise giving your footage an overall uniform look.

Here I've made some minor adjustments and saved my settings as a preset.
If you look at the corrections pane, I've gone and kept the film stock emulation at Kodak 5207 Vis3, changed the size to Super35 and dropped the grain to 30. In the 3-way color corrector I made the midtones and highlights a little more "blue," which cools off the color. Notice at the bottom the exposure sliders on shadows, midtones, and highlights: I've reduced the exposure on shadows and raised it on the highlights. This gives the image slightly more contrast, which is a look that I prefer. Again, to a degree this is a subjective process.

Step 3: Rendering

The Render screen
Rendering your files creates new versions of your video clips with the color settings adjusted the way you want them. I advise keeping your originals as I am not 100% sure Filmconvert "bakes" in your adjustments. But these converted files are the ones you will import into Final Cut Pro X.

Be sure to save them in a unique folder that you can find when it comes time to import into FCPX. Also, make sure to have the format set to "Quicktime - Apple ProRes 422 (HQ) to ensure no loss of quality.

NOTE: Rendering takes a lot of processor power. Don't interrupt the computer with needless web surfing and the like when it is rendering your files. Also, keep the computer from going asleep. I find that the ETA prediction is pretty accurate.


There is a FilmConvert Plugin for FCPX, and it is on the Studio's iMac. The only problem is that it isn't on anyone else's computer. This means that your color correction might not work on another computer if you apply it within FCPX. I'm still testing the compatibility of the plugin across campus. Stay tuned.

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