Should you shoot flat when shooting with a DSLR? I've read a bit about how it can be useful to use a "flat" profile for shooting video on a DSLR which produces only compressed video. For example as described in this article. The reasoning is that most lossy compressors (like H.264) will do more compression in the darks, removing that data and making it impossible to adjust in post. (For example, if you brighten it, you'll get bright gray squares instead of whatever data was there before compression.)

The author of the above seems reasonable. He worked at LucasFilm and has directed many music videos and feature film VFX shots. It doesn't seem like he's suggesting some fad, but is talking from experience.

In the answer to [Post-production workflow: VFX before color correction? workflow: VFX before color correction), this was included in the accepted answer:


  As far as low contrast and low saturation, I would disagree rather strongly with shooting for low contrast/low saturation. This is how you get noisy, low quality color. Your camera has a limited number of colors it can describe, if you ignore a large portion of that color space, then you can't describe as many colors and the resolution of your color after boosting the saturation and contrast will be very greatly reduced.


These sound contradictory to me, but maybe I'm misunderstanding. Is the advice to shoot flat good advice for DSLRs with lossy compression or not?
There are two schools of thought on this topic but nothing I know has suggested that shooting with a flat profile is a bad thing. Here is what I understand:

1) When shooting with Canon DSLRs, it's generally advised that you shoot with a flat profile (Technicolor cinestyle, Prolost, etc.) and over expose (but don't clip!!) and you get a picture with much more detail, specifically in the shadows. Here is a video showing this: https://vimeo.com/73909925

It's rather long, but the entire series is good. In there he specifically shows the effects of shooting standard and exposing correctly v.s. shooting flat and over exposing. Lots of detail in the shadow is preserved when performing the latter. 

2) A lot of more professional film makers (Shane Hurlbut, and Stillmotion) suggest that you should use a color profile that best matches your final color result. Less work is needed in post, and  you have a better feel for your film. I think I see this school of thought from professionals more often because the gear they own has high dynamic range and retains so much information anyways, so detail isn't something to worry about. 

Personally, I'm not a professional and I record with a Canon 550D but I use the Standard Profile when exposing my shot (aka, over exposing) and switch to technicolor cinestyle when I hit record to give me more color grading flexibility in post.