luminence and zebra's

Cees Mutsaers

Cees Mutsaers

Veteran
What is the best way/technique to determine/set the luminance in a shot. My zebraces are set at 70 and 90 % but if I put the main object in the shot at 70% most of the frame is way over exposed.
 
I set my zebras at 75% and 100%.
The 75 is close to an average white person's skin tone (which is, on average, about 80),
so if I get a little zebra on the highlights of a white person's face, I feel OK. The 100 is my
"be careful you might clip everything!" setting. It depends on what I'm shooting, but if the most important thing is a person's face, I try to make sure the background isn't bright (a sunny sky for example). I shot an interview with an apple grower the other day, under a tree in the rain. It was a little dark under the tree, but the guy was the most important thing, so I let the sky blow out around the edges. Later I shot some b-roll of the autumn leaves and hills around the orchard. The 100 setting was my friend for that.
If the most important thing is a scene that includes the sky, but no person to worry about,
I let the brightest, puffiest, whitest clouds have a bit of 100 zebra on them. Everything else is a compromise between the 2 settings.
Ed
 
P.S. if you're getting consistent good exposure with a person at 70% zebra and the rest is blowing out, you should provide more light for the person or put them in front of a darker background.
Ed
 
If you're in manual iris and you expose for a subject in the foreground, a 70 - 80% zebra should start to roll over the highlight areas. On a person, this would be the top of the forehead, bridge of the nose or shoulders where there is a backlight or rimlight in play. Whatever is in the background area is going to expose in direct relation to what's in your foreground. If the background is more than three stops over or under the f-stop of the foreground subject, you might feel that you've over or under-exposed the entire image respectively.

I use DRS on the 300 and like it. It flattens the image somewhat, but I feel like the curve helps in contrasty situations. Like HDR (to an obviously lesser extent), it gives you more flexibility in post as details are maintained in the original image.

[What Ed says!]
 
I shoot always in 1080/25p (720 gives me always soft images) and I believe dat DSR only works in 720.


Erik Olson said:
If you're in manual iris and you expose for a subject in the foreground, a 70 - 80% zebra should start to roll over the highlight areas. On a person, this would be the top of the forehead, bridge of the nose or shoulders where there is a backlight or rimlight in play. Whatever is in the background area is going to expose in direct relation to what's in your foreground. If the background is more than three stops over or under the f-stop of the foreground subject, you might feel that you've over or under-exposed the entire image respectively.

I use DRS on the 300 and like it. It flattens the image somewhat, but I feel like the curve helps in contrasty situations. Like HDR (to an obviously lesser extent), it gives you more flexibility in post as details are maintained in the original image.

[What Ed says!]
Click to expand...
 
I have the problem most often in establishing shots of scenery where the top and bottom of the frame have big difference in intensity. If I set the bottomt 70% the rest is way above 100% I than mostly close the iris a bit in such a way that the top is less overexposed and the bottom is a bit underexposed. Probably I need a matbox with a gradient ND filter right ???
 
A grad ND will solve that problem if you aren't moving the camera in a way that will reveal the gradation.
 
Well for me in PAL land those BBC settings always seem right to me, but there again I have done stills for 30 years and still use an old meter and my eyes to look at the contrast ratios on any scene.

I then fill in with light when needed, have only done one shoot at AVC intra 50 at 720p in bright sunlight where it went a bit wrong but as it was run and gun it is still OK for me, just a bit hot for you tube.
 
I think 70 ire zebras for Cauc skin tones is very old school. That's what broadcasters used to do for newscaster faces 30 years ago. the range I work in is 53 to 65 and find that pleasing to my eye in general but it all depends on the situation. Lower IRE value skin tones look more natural to me.
 
mark - while i still use (just short of) 70 for my caucasian skintone target level, i think you're on the right track - mainly because in a digital world, if it's blown out, it's gone. if you're "under" you can always bring it back up if you're in a situation where you get post-production work done. i work mainly in news, and people want to see skintone at 70 right out of the camera as i rarely have an opportunity to get things tweaked before it hits the air...
 
Most who recommend the zebras in caucasian facial highlights aren't letting anything but the shiny spots crawl at 70 or 75%. Not the whole forehead.
 
FlacaProductions said:
mark - while i still use (just short of) 70 for my caucasian skintone target level, i think you're on the right track - mainly because in a digital world, if it's blown out, it's gone. if you're "under" you can always bring it back up if you're in a situation where you get post-production work done. i work mainly in news, and people want to see skintone at 70 right out of the camera as i rarely have an opportunity to get things tweaked before it hits the air...
Click to expand...

I think its easier for skin tones to start looking a little plastic especially in 8 bit digital than it was in the old betacam analog days. I've noticed this and that is part of the reason I go lower on exposures which seems to help the plastic problem. You can also tweak a scene file especially for faces and roll into that scene file for stand ups and what have you. Maybe some thing with high gamma and high knee. You'd have to experiment.
 
FlacaProductions said:
correct - i have juuuuust a couple of z's on the forehead or brightest part of the face...
Click to expand...


Exactly. Zebras aren't a science, you have to interpret them. You decide how much zebra you allow to get the look you want. I set mine at 75% for skin tone and only allow the first sign of zebra in the skin highlights. To say that's old school is silly.
Ed
 
But when you shoot scenery (esteblshing shot) do you stop opening the iris at the first sign of the first zebra level (not regarding the sky) ?

eddo said:
Exactly. Zebras aren't a science, you have to interpret them. You decide how much zebra you allow to get the look you want. I set mine at 75% for skin tone and only allow the first sign of zebra in the skin highlights. To say that's old school is silly.
Ed
Click to expand...
 
No simple answer for that other than to calibrate your camera's VF so that when you
look in your viewfinder you're confident that how you see it now will be how it
looks later in the edit suite, at least as far as exposure goes. I have 2 zebra settings on my camera, set at 75 and 100.
If there's sky in the shot the 100% setting keeps me from blowing out the sky. If there's
no sky in the shot then it depends on what *is* in the shot, dark trees, bright granite buildings,
etc. will determine what the 2 zebra settings look like. My camera also has a waveform monitor built-in, so I use that too.
 
Your experience as a photographer is going to build and build through experience. Your acquisition format is going to drive how you compose and light your shots. Film and HDR(v) are going to be comparatively less demanding from a dynamic range and contrast standpoint. For video, you need to keep whatever you want properly exposed within a narrow(er) range of stops. I love my foreground subject to be keyed 1 to 2.5 stops over the general background values. I don't always get what I want and the subject doesn't always lend itself to this style choice.

Productions roll around with tons of grip and lighting equipement behind them for good reason.
 
I don't think you can callibrate the EVF on the HPX300 at least i don't know how to that with this cam. If you put your second zebra at 100 % when it becomes visible it can have any value above 100% so you keep the iris openend so the second zebra is just not visible in the sky right ? However when you do that the rest of the frame will be way underexposed (in 9 of the 10 cases) and the rest of the frame is the interesting part. So I think that the only solution is a gradient ND when shooting scenery or extra light when you shoot people in front of a sky as background as suggested by the other members in this thread.


eddo said:
No simple answer for that other than to calibrate your camera's VF so that when you
look in your viewfinder you're confident that how you see it now will be how it
looks later in the edit suite, at least as far as exposure goes. I have 2 zebra settings on my camera, set at 75 and 100.
If there's sky in the shot the 100% setting keeps me from blowing out the sky. If there's
no sky in the shot then it depends on what *is* in the shot, dark trees, bright granite buildings,
etc. will determine what the 2 zebra settings look like. My camera also has a waveform monitor built-in, so I use that too.
Click to expand...
 
Erik I don't have the faintest idea what you are trying to tell, it goes beyond my comprehension, I am just a newby in video so maybe you can explain it again in simple words ?

Erik Olson said:
Your experience as a photographer is going to build and build through experience. Your acquisition format is going to drive how you compose and light your shots. Film and HDR(v) are going to be comparatively less demanding from a dynamic range and contrast standpoint. For video, you need to keep whatever you want properly exposed within a narrow(er) range of stops. I love my foreground subject to be keyed 1 to 2.5 stops over the general background values. I don't always get what I want and the subject doesn't always lend itself to this style choice.

Productions roll around with tons of grip and lighting equipement behind them for good reason.
Click to expand...
 
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