Changes in Latitudes, Changes In Attitudes
I have held firmly to the belief that when shooting digital video, it is prudent to shoot with a picture profile or camera settings that gives you a flat clean digital negative allowing for room to create the final look in post.
This was only reinforced after reading the excellent DV Rebel’s Guide by Stu Maschwitz. Some people disagree with Stu and I and think you need to lock your look in camera as this will not only save you post production time, but when you bake in the color it’s embedded in the camera before it’s compressed to file (or tape), meaning less potential noise in the image.
That’s all fine and good, until you’re editing, and you realize you need the emotional push of a scene to change or it needs a little boost. Now if you want it to be cool rather than warm, or even worse less contrasty, you may not have fluidity to make that change, and your efforts to have less noise may now be yielding more noise as you push and pull the colors and contrast levels.
This is one of the reason’s why people still love shooting film, or using the RAW files from the Red One, or in their DSLR stills. By working with the RAW sensor data, these formats give you the opportunity to change your mind, and process the image to your liking much like traditional film negatives.
In my previous camera the Canon XL2, I researched forums like DVinfo.net, and was able to cull most of the users preferences for creating a flat look. I tried them all and shot tests and mixed up different variables and ended up with my recipe of parameters to get my flat digital negative, and it served me well. That said, it wasn’t always rosy, there were moments during post on Mercy where I wish we had baked in a little more red to that “digital negative”, to help make the skirt and mask pop as much as Tony wanted. I had to push it pretty hard in post, and that resulted in some noise and artifacting, one of the drawbacks and concessions of shooting digitally to a compressed 8-bit medium like DV. That also taught me the lesson to shot flat, but with a look in mind, and to always shoot tests to achieve that look before shooting as you may find you want to tweak your flat profile to achieve it.
So when it came time to set up my new Canon EOS 7D, I wanted to create a new baseline digital negative profile. However I was concerned, because it records to an even more highly compressed, 8-bit, 4:2:0 color space format, and I didn’t want my color corrections falling apart. It didn’t take long to learn that I wasn’t the only one with concerns, or trying to find that flat digital negative. In fact, I found that there are lots of custom profiles out there for creating a flat look, including one from Stu himself. (His settings were actually for the 5D but they work just as well on the 7D.) I also found just as many arguments against this due to the codec in the camera breaking down and causing noise and color artifacts in the footage, as I had already feared. As with everything in life, your mileage may vary so as I did before with my XL2, I downloaded all the presets, read the forum posts, and then shot some tests using each of the profiles to see for myself.
For my tests my Wife art directed some of her antique Kokeshi dolls on a tray with some fruit and vase in the background, giving me a nice interesting and colorful still life to shoot. I setup the 7D on a tripod with the canon plastic fantastic f1.8 50mm lens. (I know I should upgrade the lens, but I already owned it, as it was just fine for stills. One step at a time, people!) I shot indoors with a soft mid morning natural light coming into the room, and a little fill bounce. Set the aperture to F1.8 for some bokeh. Set the camera to the built in neutral setting for exposure. Set video to 1080/24p, shutter to 1/50, and ISO to 640.
- TIP: I set exposure by rolling 2 seconds and then playing it back to see the histogram, in camera. Adjusting until I got it right. Man, do I miss zebra stripes.
Above is the image, with and After Effects levels effect showing the histogram in 32-bit mode. This is the original untranscoded file, and you can see the “gaps” in the histogram showing the lack of color information from the 4:2:0 sampling. My exposure technique obviously still needs work. I’ve had the camera a week so I’ll cut myself some slack. I didn’t clip the blacks, and the whites are right there on the hairy edge with a little highlight clipping. This profile does what it says and gives you a neutral image, but with Canon’s built-in contrasty gamma curve.
I used a laptop tethered to the camera so I could upload the many picture styles quickly. Then without changing the aperture, iso, or shutter I cycled through each of the following camera settings and rolled 5 seconds of video for each one.
The standard profile obviously is much more contrasty and saturated. You can see I lost some latitude in the exposure as the highlights clip. (The tall thin line on the right).
Stu’s settings, the only one that uses the in camera controls only.:
It looks pretty good. It achieved our goal of added latitude by pulling in the exposure to optimum levels, and flattened out the contrast without squashing the midtone details. I tried a few aggressive Magic Bullet Looks (hereafter referred to as MBL) presets, and it held up well (see the bottom of the post for an example).
The Genesis Panalog WIP 4, is definitely still a work in progress. It doesn’t look like a panalog file to me, it crushed some of the blacks, but rolled off the highlights OK, and seemed to over saturate the color. When I attempted the same MBL presets as I tried on Stu’s settings it did not hold up well, showing artifacts and banding in the saturated colors.
The Marvel Cine 1.2 picture style, was designed to emulate the Cine-Gamma curve of Sony EX1. Much like Stu’s settings it flattened the contrast without losing midtone details but didn’t really gain as much in latitude based on the levels results. It held up OK, using the MBL presets, and I obviously didn’t shoot with real skin tones for this test, but I did notice in some others that skin tones would get orange.
Superflat was designed by a Neil Stubbings on Cinem5D, and it gave me similar results to Marvel Cine, but it featured more strange color shift, and the same color artifacting issues that Panalog suffered. In fact Neil has since posted that he’s stopped using his own profile and now uses Sharpness all the way down, contrast, all the way down, saturation down 2 clicks. Exactly Stu’s settings above.
ExtraFlat by Eugenia is a modification of the above Superflat, and really seemed to be a winner giving apparent additional latitude, and an even flatter less contrasty look than Stu’s settings, without the color shift. It also seems to hold up under aggressive color correction from the MBL presets. However, I really had to play with the correction a lot more, and push the effects alot further to achieve the same results with ExtraFlat as with Stu’s settings. Additionally I saw that ExtraFlat doesn’t pull the sharpness down all the way which I would modify if I were to use it. I find it’s better to dial that sharpness in later in a more controlled post environment.
Overall I am leaning towards Stu’s settings because they held up so well and the ExtraFlat had to be pushed much further than I’d like which could create more potential for noise.
I’ve also found that I can achieve even better results by transcoding the native camera .mov files to Cineform files. When transcoding to Cineform, the codec conversion interpolates the color space to a 4:2:2 10-bit file, that’s not only more robust to color correct, but easier to edit.
Since I started this test, some more very smart and experienced DSLR shooters have done some additional testing. Most significantly, the folks over at Zacuto did the The Great Camera Shootout comparing several DSLR’s versus 35mm film. The results may surprise you, but what I found interesting was this quote from Phillip Bloom as to how they set up the cameras
For those who are interested I discussed at length with Tim Smith of Canon about the best picture profiles for the cameras. We settled on in camera settings, many will argue that we should have gone “superflat”, and I am sure it would have been great but in the end what we went for was sharpness all the way down, Contrast all the way down and Saturation down two notches. The reason we turn sharpness all the way down is simply the camera is too sharp and it also accentuates the flaws of the camera. It’s very easy to bring back a little bit of sharpness in post. That is my recommendation. With the flat PP I was able to get about 2 stops more latitude in these cameras.
Wait a minute… those are Stu’s settings… I’m starting to see a trend here.
Then Shane Hurlbut blogged his feelings on color correcting DSLR footage, adding the concept of adjusting the white balance of your camera to remove any inherent bias, then using a very slightly modified custom gamma curve to create a RAW file.
I’ll have to give that a try next. For now I’ll stick with Stu’s settings. Below is an example of the shot with the MBL Blockbuster Preset, showing how it holds up to an aggressive look. Mouse over to compare it to the straight camera look.
- EDIT: Technicolor has now released a picture profile specifically designed to get the most latitude out of Canon DSLR’s. Our post on that here.
Via John August a series of videos by the Academy of Motion Pictures Arts...