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Your definition of "Quality of Light"


Stephen Sanchez

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DPs, new and established,

I've seen many shooters refer to "quality of light" in conversations. I've seen it used in descriptions comparing fixtures, diffusion types, soft/hardness, color, color-temperature, and I think even source placement. There are blogs and videos that tout the same random interpretations, sometimes combining them.

No doubt, shooters here will have the same difference in opinions on the use of the term, and I'm curious to know what that is.

So, what is your definition of "quality of light?"

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‘Quality’ in this case refers to how hard or soft the light is. A point source that is very small relative to the subject, like the sun, is the ultimate hard source. The harder the source, the sharper the shadows.

A diffuse source that is very large relative to the subject, like an overcast sky, is the ultimate soft source. The softer the source, the more the light wraps around the subject, softening the shadows. ‘Quality of light’ describes the range between these two possibilities.

The other common terms used to describe light are Quantity, Color, and Direction.

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I'm not a DP/Cinematographer but a photographer 32 years and counting but anyway haha, for me quality of light is the difference to a scene made by light that comes in at different times of the day if natural or set up plus of course the colour it comes in at thats either cold, neutral or warmer

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4 hours ago, Stephen Perera said:

I'm not a DP/Cinematographer but a photographer 32 years and counting but anyway haha, for me quality of light is the difference to a scene made by light that comes in at different times of the day if natural or set up plus of course the colour it comes in at thats either cold, neutral or warmer

Yes, I think the term has different connotations in still photography, especially if you’re dealing with natural light much of the time. You will also find cinematographers who use the term this way when describing a general look to the director or colorist. 

The purpose of having the specific terms of Quantity, Quality, Color, and Direction in cinematography comes from the need to communicate with the gaffer and the lighting crew in order to get the result you want. It helps them order the right lighting units, gels, and rigging gear that might normally not be on the truck.

If they know that you want a 5600K light, 4 stops over, filling the kitchen window and coming down at a high angle from camera left on the scout day, then they can order the right gear to make that happen on the shoot day. And see if it’s even in the budget to do.

With regard to Quantity, if you can tell the gaffer roughly how many footcandles you need out of the big units, even better. You may have some special camera effect like over-cranking or cut-shutter that will affect the exposure. But if you factor that into your estimate, then the gaffer doesn’t need to worry about it.

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I tend to use the term "colour quality" to talk about spectral content, although I'm not sure it's that widely used. The phrase "quality of light" to me refers to spatial distribution, which a sophist's way of describing the source size and degree of collimation, or how hard or soft it is.

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Like I said, it's a vague term -- in the abstract, it is used on film sets to refer to the softness or hardness of the light. But one can reapply the term to talk about the color reproduction of an LED, though one is more likely to say "color quality" than "light quality" in that case. Or one can talk about the softness or hardness of an LED light.  But CRI or TLCI are about color -- you can call that "color accuracy" or "color quality" or "color complexity", I don't know, but color is the operative word, not light.

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It's like pornography: you know it when you see it.

But more to the point, I think it's better to talk of light's qualities, plural, rather than its quality. Not that I disagree with any of the above.

Sometimes your camera can't properly capture what you see, but that's a different discussion.

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Yes. The hard/soft definition is what I learned too. Yet I've since found the term used for anything it seems, which may be from lack of understanding by the user or perhaps ego mouth noise. So I was curious what shooters here thought it was. Afterall, what's the point in existing a term in our field if its use is random.

But as David pointed out, it's still vague. How do you tell a gaffer "I wan't a big quality of light coming through that window"? What does that even mean? It's impractical for communication or description. He's going to ask what size and weight rag you want, or perhaps how hard/soft. The term itself is subjective. And I suppose I have beef with it at this point. Because there are more concrete words to use instead of every instance "quality" could be utilized. There's no point in it existing.

Due to this, I believe the term to be archaic for cinematography. Literally obsolete. There are clearer words in commonplace when describing a source or diffusion. Which we use everyday, those of us lucky enough to light a lot. And I hope those of you in positions who may one-day teach, or mentor, will help correct or guide the newer generation away from that nonsense term whenever you see or hear it. Which they've likely learned from youtube or videography blogs claiming to tell the secrets of "what you need to know."

Basically. I think we should stop using the term and tell others that it's not a real thing. Because nobody will understand you when you try to use it, anyway.

I'm all for the betterment of understanding lighting and that term seems to employ the opposite effect.

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Just because the term may be vague (quality, not Quality) doesn’t make it useless or obsolete. Concrete terms like Quantity (footcandles/beam angle), Quality (hard/soft), Color (Kelvin/mired shift), and Direction (position, height, angle) are useful for quantifying and communicating what you want to other technicians on set. But we still need a way of describing our vague memories of light and the feelings you want to capture with lighting - that’s part of cinematography too. 

I had a director once describe to me the quality of light she wanted for a scene as ‘the way the sky turns green before a tornado comes.’ She was from Texas. I had no idea what she meant, but I did my best to get that quality with Spring Yellow gels. It was probably not accurate at all, but it did give a strange unsettled quality to the scene.

Another time, a friend and I were driving back to the Bay Area from LA after renting a camera package and came across a dark red sky, from smoke fueled by wildfires along Hwy 5. We drove for hours in what seemed to be magic hour conditions. We pulled out a color meter, took notes and re-created the effect later on in the project.

The critical component in each case was the feeling of the light, and trying to break down what the light sources in nature were. Where was the sun? What was diffusing it? What were all the secondary reflective sources? It’s only once you break it all down that you can start to quantify how you’re going to reproduce it on set.

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These are all great points, used for emotional or abstract communication. That's a great use actually.

I do consider the same technical details about light as you do as well, but consider "Quality (hard/soft)" to be Size(hard/soft). I also understand that might sound at this point like preference or semantics.

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6 minutes ago, Stephen Sanchez said:

I do consider the same technical details about light as you do as well, but consider "Quality (hard/soft)" to be Size(hard/soft). I also understand that might sound at this point like preference or semantics.

Sure, ‘Size’ would work just as well. ‘Quality’ is just what I was taught to use, but it’s the same thing really. 

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On 8/15/2020 at 3:44 PM, Satsuki Murashige said:

I had a director once describe to me the quality of light she wanted for a scene as ‘the way the sky turns green before a tornado comes.’ She was from Texas. I had no idea what she meant, but I did my best to get that quality with Spring Yellow gels. It was probably not accurate at all, but it did give a strange unsettled quality to the scene.

I found a frame:

MercyandTides_00001.jpg.c4d703153b6e1e24bf276a7640a5af02.jpg

 

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That’s funny because I had an episode of “United States of Tara” where a tornado hit Kansas City where the show was set (though filmed in the San Fernando Valley) and the family rushes outside to what the script described as a “weird light” and a lot of wind. Well, that month in 2010 (I think) there were all these wildfires burning around the city and the sunlight had a weird red glow to it, made worse by the fact that on that second season I was told by Showtime that I couldn’t use PanaLog anymore on the Genesis, I had to record Rec.709 (they didn’t want to pay for the log-to-709 conversion). Panavision recommended I turn Knee Sat on but when the weather got weird from the fires I got this reddish clipping on skin tones that I traced to the Knee Sat setting. But it did give this tornado sequence an odd feeling!

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That’s crazy that the studio wanted you to shoot Rec709 on a drama! I bet they regret that decision now.

I love it when writers and directors pay attention to the quality of light around them and incorporate it into the story. It’s something shared that all of us can feel from our own life experiences, and in the end it’s up to the cinematographer to figure out how to recreate it. Then the lighting ‘style’ really becomes part of the storytelling, not just aesthetics. It makes the job so much more engaging.

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I grew up in the Midwest and that green light before a tornado is actually really creepy. There’s a lot of yellow in it too. Like a sunset without the sun.  I haven’t seen it for probably 20 years, but it’s a really weird, impending, look that feels like it just washes over everything when you’re outside. Now you got me thinking how I would re-create it. If it were exterior (I see your shot is interior so that’s a little easier), I’m not being very creative, but I can’t think of how else to do it other than shoot in overcast and add an overall green/yellow tint in post. Or maybe a light green filter if you wanted to do it in Camera? But you would obviously have more control about where you want it heavier and lighter if you did it in post.  I don’t know. Your shot looks good, though.

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10 hours ago, Satsuki Murashige said:

That’s crazy that the studio wanted you to shoot Rec709 on a drama! I bet they regret that decision now.

Showtime was sort of a victim of their own success - they were one of the first companies to embrace digital photography, which mainly meant recording in a display gamma, other than the modified "hypergamma" settings in Sony cameras for extended range. So they were used to the series DPs delivering something that was more or less finished out of the camera, and not having to pay for log-to-Rec.709 conversions for dailies.

But "United States of Tara" was produced by Dreamworks and Spielberg insisted that the pilot be shot in 35mm film (I didn't shoot that one.) So when I interviewed for the series, their expressed concern was maintaining the 35mm film look of the pilot at a time when Showtime was mainly shooting shows on 2/3" HD 3-CCD camcorders in Rec.709. This was the summer of 2008 right after I shot "Jennifer's Body" (written by Diablo Cody, who also wrote "United States of Tara", which is how I think my name got passed on for consideration.) I told them that the Panavision Genesis camera was the best solution, having a single 35mm sensor and being able to record 10-bit log gamma. So the first season was shot on that camera recording PanaLog on HDCAM-SR tape.

Second season starts and I am told that Showtime doesn't want to pay the extra cost of the log-to-Rec.709 conversion for dailies, which they didn't have to pay on their other shows (like "Weeds", "Dexter", etc.). The problem with recording Rec.709, even in a flatter gamma like HyperGamma (which didn't exist in the Genesis), is that you don't have the extended highlight protection of log recording that allows you to then use (in the final color-correction session) Power Windows and luminance keys to pull detail in hot areas like lampshades, curtain sheers, etc. All you really have is knee compression to help.

So I went into the menu of the Genesis and created a version of HyperGamma plus knee compression, but with Knee Sat turned on at Panavision's suggestion. It was better than straight Rec.709 but wasn't as good as PanaLog so I lost some detail in the brightest areas along with some of the film look. And then the fire season with all that smoke in the air started shifting the wavelengths of sunlight to the red and the settings in the camera were causing some weird color casts on the brightest parts of the skin, which I traced to Knee Sat being turned on, so I turned it off.  Finally I had a backyard wedding scene in the final episode that was an all-day shoot in hot sunlight and the plan was to float Grip Clouds over the yard since a condor couldn't reach that area with a flyswatter. Then the worst windstorm to hit LA in years happened that day and we couldn't stop shooting.  The wind made it impossible to use any overheads and I decided to switch the cameras to PanaLog to deal with the harsh light, so dailies came back in uncorrected PanaLog (which is not that odd-looking compared to the much flatter ARRI Log-C).  No one at Showtime noticed and I realized I probably could have shot more of the season that way.

Third season comes up and I ask the post supervisor to look into the cost of log-to-Rec.709 conversions for dailies. Turns out it was only $1000 per episode!  So we found money in the post budget to cover it and I shot the third and last season in PanaLog.

The other problem that came up in the first season in 2008 was that many post houses back then did not have a software-based LUT system to convert log footage and were renting the Panavision Genesis GDP box (the same box we used on set to convert PanaLog for viewing on the Rec.709 CRT HD monitors) -- and Panavision was complaining that for every Genesis camera out there, they needed twice as many GDP boxes because the post houses needed the boxes as well. In time, the post houses bought software-based conversion tools.

Unlike the later Sony F35, the Genesis didn't have a way of generating a Rec.709 version for the viewfinder and monitor output while at the same time you recorded PanaLog. The other problem with the Genesis was the BNC connections to the HDCAM-SR deck, there were two sets of connections, one with a clean feed and one with the viewfinder and time code information overlaid on the picture, so sometimes when pulling the deck off for Steadicam moves, the ACs would plug into the wrong video out and your image had viewfinder information burned in. One time when this happened on a Genesis pilot I shot, we could save the image by zooming inside the information along the frame lines but the other time we couldn't because we had the crosshair lines turned on!  You'd only catch the mistake if you checked playback after recording and caught that the viewfinder info was visible.

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If you ever get pushed into burning in REC709 again in Sony world .. I recommend the new Sony REC 709 color  .. S Cinetone ..  I eventually got to shoot a job on S Cinetone with my Fx9...  its really very nice .. a world away from the old Sony look..   alot more head room .. and nice roll off in the highlights .. nothing like Slog3 of course .. but really a massive improvement.. 

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Jeezuz... Thanks for the detailed run-down. I didn’t realize those other shows were also shot in Rec.709! I guess that’s a testament to the cinematographers working on those shows who made it work. Still, it seems like a terrible short-sighted decision on the studio’s part. 

Weren’t most HBO shows around the same time still shot on 35mm? Many of those shows still look great other than the occasional iffy VFX shots. 

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Keep in mind at the time, HBO had twice the subscriber base as Showtime... and the shows had twice the budget.

Showtime embraced 24PHD soon after it arrived in 2000-2001 ("The L Word" in 2004 comes to mind, shot on the Panasonic Varicam), and there were no log-based cameras other than the Thomson Viper in 2003 and that was troublesome to use because of the uncompressed HD output to early data recorders, and then all the back-ups that had to be made to LTO tape (or Panasonic D5 tape I think) because the post houses didn't have a way of storing mountains of data.  The Dalsa Origin also debuted in 2003, and the ARRI D20 in 2005.

When the HDCAM-SR tape format came out in 2003 and then the portable SR1 deck came out along with the Genesis camera in 2005, that made the Viper (and the D20) more usable. The early 2000's involved the switchover from video engineers to DITs in order to basically set levels in the HD camera for color, contrast, etc. in a Rec.709 recording that was more or less broadcast-ready.

All of this meant though that Showtime was a bit slow to embrace the rise of more film-like log-based and raw-based digital cameras until there were simple and affordable workflows for log-to-Rec.709 dailies conversions and for data storage.  

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