Level of Blacks for Silhouette or dark scenes (4 replies and 2 comments)
Hello Roger I hope you and James are well. I wanted to ask you something about dark scenes and scenes where the character or something is in silhouette. My question is, when you shoot, those parts that look like absolute black, must they be cliping on the lut? but not in the raw or log. How do I know where to go? sorry my english is very bad. and thanks!
I don't understand what you mean by the black 'clipping'. I don't light off a monitor or from a wave function so that makes no sense to me. I will always judge the shot by eye and a silhouette is only black relative to what it is in relationship with.
Thanks for answering Roger, I did not explain well but your answer answered my question. thank you very much!!
Elpolloenano, you might be confusing yourself a bit by simultaneously thinking about what "black" is in digital images and how to light for a silhouette. Hopefully when you shoot, you've already picked a recording gamma and then a display gamma that gives you a contrast range and black level you like for the bulk of scenes, and then you light a shot for the look you want.
If you are asking about what black is in digital, it's basically "0%" (zero) on a waveform monitor reading the image in the display gamma. If your waveform reads the log gamma version, then your black may be a bit higher than zero, it may be at 10%... but as long as it appears black in the display gamma (again, 0%) then it will look black. Now if you want to figure out how to match that with your spot meter and selected ASA on set, you'll have to shoot some quick tests to determine that. When shooting film, I generally figured that most shadows would fall to black in a print off of the negative (again, display gamma versus log gamma) when they were at least five stops underexposed. Now if you are using an incident meter, then obviously a white object will fall the black slower than a black object would.
But in terms of getting a good silhouette, it is more about the highlight you frame the unlit object against, that brightness difference that creates a good cutout shape. Of course, you can have a dim silhouette in a very dark scene (like a black shape against a moonlit window) or you can have a more high-contrast silhouette (like a black shape framed against a bright daytime window.)
I'd also add that technical black level in a film print (at the deepest, that would be called D-Max, maximum density possible in the print) is determined by the printer lights used to make the print. You could develop some unexposed negative (i.e. no exposure, all black, or all clear on the negative) and then print it from 1 to 50 on the printer light scale and then project that print and see that the higher the printer light value, the deeper the black until it couldn't get any blacker. That usually starts near the middle of the scale in the 20's up to 50. So you want your footage to be exposed so that it prints in that range IF you want a strong black (not every DP does, there are some examples of movies that deliberately went for weaker, smokier blacks.)
You sometimes hear the phrase "crushing the blacks", which means pushing down the shadow detail in color-correction (or with a LUT) until it goes darker -- actual shadow detail that appeared in normal display gamma gets pushed below 0% so that some or most of it goes black. While you can do a little of that in color-correction, i.e. add more contrast to the shadows, etc.... at some point it starts to look artificial and stylized so it is better to try and control the lighting for that effect, for a more natural look.
However, there have been movies that work with a special LUT that simulates the effect of, let's say, a skip-bleach print or reversal slide film, where a lot of contrast has been added for a stylized look; in the display gamma version either the shadows are dropping faster to black or the highlights are clipping faster to white (the second is less commonly done).
Thank you very much dmullenasc , I have learned in your answer much more than I expected, you clarified doubts that I had always had. Thank you for being so kind and generous in sharing your valuable and deep knowledge.