Exposure: clipping/crushing | Art/Tech aspect + quality control

[Daniel Zlobin]

Hello everyone,

A bit funny question to ask, considering the fact that I am not new to the job. But it’s also about the pipeline, which is different from country to country, I guess. So would really appreciate the experience exchange, since I just recently moved to North America. 

This year I suddenly found myself extremely self-aware about the clipping in white (but the part of the question goes for blacks as well) and exposure in its technical aspect and it’s bond with artistic needs. 

I studied cinematography in Russia, at the time, when professors had no clear idea on shooting digital, and I was raised in a way, that you shouldn’t clip ever, beside some small spot, super white, like let’s say small patch of reflected light in the rim glasses. Same with blacks - you kind of have to have some information anyway, allowing only very little of absolute darkness in inside the frame. The same goes to TV production, let’s say you are doing a scripted, narrative tv show. You have to control the whites and blacks and never have them clipped or under; let’s say 10 IRE. Even if it’s a window, which supposed to be “burned out” you have to kind of keep it slightly below clipping, so there is at least a bit of information there (at least false color indicated that). Otherwise, if you don’t follow the principles, you get a comment on the dailies from post production team (or “department of technical quality”) next morning; and if you won’t start to be more careful about detail in whites and blacks, you won’t make it till the end of the show. 

So, colleagues, I am wondering, how is it in your experience, particularly North America or Europe? Is  it “legal” to burn out, clip, if it works for the story, or the scene? If it’s the look you agreed with a director on? Is there any higher authority, any “clip police”/“department of technical quality” in the post production, which might not approve “clipping” or “crushing” in the footage, like TV channel, for example, or other “technical control” crew? How is that process is in the film production? 

I re-watched Kubrick’s “Shining” in the theatre just the night before, and there are some shots, where windows and some other details are definitely “burned out”. Yes, it shot on film, so clipping might look not so bad, and yes, maybe the copy was not the best, but still, the concept is that it is burned out. The same with “Equalizer-3” l, the most beautiful scene, in my opinion, is the first scene, where protagonist is backlit and absolutely beautifully burned out. 

Appreciate a lot your input. And yes, the same question goes to attitude towards blacks - am I allowed to have them deadly 0 if I really want to? 

Roughly, the question is: am I allowed to clip whites and crush blacks if I really want (and we agreed on it with director) and is there any technical commissions at some point in the pipeline to deal with on those matters?

I  personally always tend to fit everything in the dynamic range, but I am curious about your experience on this subject. 

Thank you so much. 

[David Mullen ASC]

Some broadcasters will look on scopes to make sure the signal isn't being clipped obviously but with something like a whited-out window, it doesn't necessarily have to be at 100% on the scope or it could just be touching that. As long as it doesn't look like a mistake. You wouldn't want a medium shot of someone in a white shirt having it clipped with no texture/detail because that's ugly, distracting, and artificial-looking.

It gets tricky with something like a scene in a white limbo space because if you expose the white room too low, you often see unwanted texture, scuff marks, shoe prints, etc. but if you push it too hard past the clip point, a broadcaster might reject it. So it takes some massaging in post to blur the details in the whites and then keep them just below 100%.

The problem with a film transfer is that you need the ability to apply luminance keys, power windows, and knee compression in order to get the white areas near the clip point but the rest of the image to the level you want.  In other old days of telecine work in the 1990s I found that some cheaper rooms didn't have knee controls so they would just set the transfer so that a bright light like a hot fluorescent tube was just below 100% even if that meant the whole shot now looked too dark.

I was thinking about this issue while watching "Space: 1999" -- they clearly modeled some design work on "2001" with the frosted lighting panels but rarely used them to light scenes. Partly because in order to create mood, they wanted a harder lighting style at times, but I also think the cinematographer, who had to deliver a film print to be shipped to TV stations, had to work around the fact that the film chains would set the exposure based on the brightest thing in the frame so if the panels were too hot, even though the film emulsion could handle it, the TV stations would start complaining about large parts of the frame hitting 100 IRE. Whereas "2001" was shot for theaters and eventually when TV stations showed it, they'd have to accept the photography whether they liked all the whiteness or not.  Same for "THX-1138."

[Daniel Zlobin]

Hello, David
Thank you for your response, appreciate it a lot. 

11 hours ago, David Mullen ASC said:

Some broadcasters will look on scopes to make sure the signal isn't being clipped obviously but with something like a whited-out window, it doesn't necessarily have to be at 100% on the scope or it could just be touching that. As long as it doesn't look like a mistake.

Just to make sure, do I understand you correctly, that basically, for example, in case with "Equaliser" (pic in first post) the whole backlit, hot area on the head is kept slightly under clipping, having only the glowing part maybe a bit over?
Or do you mean that generally, both, in film and TV you might have clipping as long as it doesn't look like a mistake?

And may I ask you, when you are exposing something tricky, are you tend to go safe and have hot areas (like certain part of the cloud in the sky or part of the bright window) unclipped even with REC 709 lut applied, or you may let them clip, in case you see that they are not clipped in RAW original footage?

Thanks! Daniel 




 

[David Mullen ASC]

Considering that they shot on the Alexa 35, probably only the brightest highlight was clipped if that, just like when the sun kicks off of a shiny car. But I don't know for sure.  If anything, it's hard with the Alexa to get a hot highlight to burn out and halate so often that has to be enhanced in the color correction.

A clipped highlight is acceptable if it is a small area -- when someone momentarily hits the lens with a flashlight, you don't expect to see the filament of the bulb except in the tightest of insert maybe.

For the most part, you expose scenes to minimize clipping to very small areas so that you have control in post over them.  But in the grade, you may decide to let more things burn out.

For example, when I lit this scene, I wanted to make sure the pattern in the sheers was captured, but my DIT pointed out to me that the round circles inside the sheers' pattern were clipped. But that just meant that those circles were white with no detail, which I was fine with -- I didn't want to underexpose the scene further just to hold texture inside those little circles, I'm not sure there was even any texture there anyway.
 

Or in this scene, I exposed so that the individual globes of the MoleFays were captured but I didn't need to record detail inside each globe.

Or here, this set was on a stage -- I had a white sheet hanging beyond each window but was counting on the Molebeams, smoke, and dirt on the glass to burn out the window, otherwise you might see the wrinkles of the sheet hanging out there when if you saw anything it should be a farm landscape. But the Skypanel lighting coming through the frosted ceiling panels was dimmed to the level to hold some detail in the panels.
 

[Aapo Lettinen]

I find it very funny that distributors are furious about staying inside "written in stone" picture standards with no possibility for any kind of artistic expression in term of how things clip or crush, but inaudible dialogue mix and horribly loud music with almost unusably low foley+atmos+dialogue is somehow magically OK and allowed as an artistic method even if it makes it impossible to watch the end product without the viewer self adjusting the volume continuously up and down to be able to follow the program

[Aapo Lettinen]

I would rather take clipped and crushed image than needing to have my hand on volume button all the time when watching and still not hearing a good enough  mix to complete understand what the characters are talking about. One could shoot the movie on umatic and still have better end result than the current stuff where the soundtrack is crushed and inaudible even when the picture is gorgeus

[Daniel Zlobin]

22 hours ago, David Mullen ASC said:

A clipped highlight is acceptable if it is a small area -- when someone momentarily hits the lens with a flashlight, you don't expect to see the filament of the bulb except in the tightest of insert maybe.

Thank you so much David. 

Good thing, that it’s quite the same place I’ve been in my mind, but I was never certain about it, and it is really great to get such detailed answer from you. Thank you for the examples and stills as well. 

Appreciate your response a lot. 

 

[Daniel Zlobin]

21 hours ago, aapo lettinen said:

t inaudible dialogue mix and horribly loud music with almost unusably low foley+atmos+dialogue is somehow magically OK and allowed as an artistic method even if it makes it impossible to watch the end product without the viewer self adjusting the volume continuously up and down to be able to follow the program

Good point, that’s really true about some films this days, when it’s really hard to get the point of dialog, as it’s really low comparing to other sounds