Getting Correct Exposure - Need Advice

[Mitchell Lewis]

I'm using an EX3 with a Letus Ultimate adaptor. I've got the zebra set to 95% and I'm shooting with CINE4 and HIGH SAT and some reduction to the black levels (setting that Doug recommends in the Vortex Media training DVD's).

Matrix>Setting: On
Matrix>Select: High SAT
White>Preset: 5600k (as done in item 12)
Gamma>Select: CINE4 (identical as the F300 cameras)
Black: -3
Black Gamma: -2

Anyway, I seem to be under exposing much of the footage I'm shooting. A friend of mine was with me on my first shoot with the camera and he pointed out that colors look better if the footage is a bit under exposed. So I've been trying to shoot with just a touch of zebra. This becomes a problem when I have a bright light in the distant background. The light may only consist of 3% of the entire frame, but it can show strong zebra. In this case I usually forget about it, and expose on the rest of the frame.

I find myself using the Levels control in AfterEffects quite a bit to correct under exposed footage, so I've gotten used to using a Histogram. So on my last shoot, I tried turning on the histogram and I liked it. Does anyone else shoot with the Histogram turn on? Any other advice? Maybe it's because this is the first time I've used a camera with CINE GAMMA and I'm not used to the "look" of it. Dunno.... Could also be my viewfinder settings. I set them up to color bars, but maybe the knobs have gotten bumped? (thinking about putting gaffers tape over them)

[Brian Luce]

Why do you set your zebra so high? The secondary zebra is preset at 100. Most are setting there primary at 70 or 80. I'd start with that.

[Mitchell Lewis]

Thanks Brian. Could it really be that simple? I'll try it.

[Bo Skelmose]

If you do have a lot of white in your picture, you have to accept zebra's. I have my zebra set to 95 and I have learned too work with that. I do knot know the cine settings - but you have to mess with the knee and slope settings. If you dont, the camere will not compress the white and white will blow out. It's been discussed in other threads and that helped me with my problems of exposure.

[Brian Luce]

Originally Posted by Bo Skelmose

I have my zebra set to 95 and I have learned too work with that. .

Same question, if the secondary zebra is already set to 100, why set the primary at 95?

btw, tried auto exposure in what would not be considered severe conditions and it clipped.
Auto bad. Manual good.

[Mitchell Lewis]

Thanks everyone. I'm going to try setting my zebra's back to 70 (factory default I think). I never shoot with auto exposure or auto focus.

Nobody ever uses the Histogram?

[Andres Papousek]

Originally Posted by Mitchell Lewis

Nobody ever uses the Histogram?

I think (my percepption) that histogram only work to get a general idea of all the exposure values of your frame.

I use Zebras at 70 or 75 to see "correct iluminated caucasic faces"
Then Zebras at 100 to know where are my Whites
And marker (don't remember the exact name), wich is this tiny square with a changing percent value in the midle of the Lcd screen, to read exposure in any part of my frame.

I find really usefull this last feature. Is like have my Spot meter inside the camera. If you understand Zone sistem (ala Ansel Adams) this will help a lot more than the histogram, couse you know exactly how bright is that spot of your scene, and that lampshape, and the dark side of that face, and that shadow down there etc. etc

Trying to read all this with the histogram, is guessing, becouse that spike in the medium exposure values could be the face of your talent or the abstract art picture behind him.

If Sony change the histogram for a Waveform in the next firmware update I will make a conmemorative monument here in Tegucigalpa, with old "bronce VHS tapes" LOL

Any way, at the end, it does not matter wich tools you use for exposuring your image only how it looks at the end of all the process.

Andres

[Mitchell Lewis]

Well put Andres. I'm going to try some of your suggestions on my next shoot. The "shot box" is especially intriguing.

[Leonard Levy]

For HD most people are putting faces around 60 - 65 instead 70 these days.
Probably on the low end for a cine gamma but I don't use it so that's just a guess.

[Andres Papousek]

Originally Posted by Leonard Levy

For HD most people are putting faces around 60 - 65 instead 70 these days.
Probably on the low end for a cine gamma but I don't use it so that's just a guess.

Mitchell, Maybe I have to doble check my numbers and 70 is to much couse I think Leonard is right. Any way the idea is the same.

[Mitchell Lewis]

Thanks again everyone. I'm anxious to try this for my next shoot, but I have nothing scheduled until next week.

[Mike Chandler]

I tried using histogram as a quick way to get good exposure, shoving everything to the right and then backing off, as you would do with a still camera with RAW footage, but results were uneven depending on lighting situation. A better approach is to spend a lot of time testing and getting your viewfinder calibrated to your monitor, so that if it looks overexposed in the viewfinder, it really is overexposed. With the exception of hot spots, which zebra picks up, this works for me. And I get very different results than if I use Auto.

But I do find auto helpful on a complicated exterior shot, such as long zoom in or out with focus change and big exposure change from cu to wide or vice versa, where change is slow enuf not to notice and auto helps you bridge that big exposure divide.

[Mitchell Lewis]

Thanks Mike, I'll keep that in mind. Good point about setting up the monitor. With our old Canon XL-1S I got pretty good about just "seeing" a good exposure in the viewfinder. Not using zebra's, histogram, etc... Maybe I just need to get used to this new viewfinder.

I watched the Vortex Media Training DVD again and Doug (the trainer) made an interesting comment. He said "personally I think it's better to err in the direction of overexposure rather than underexposure".

On my first day of using our new EX3, my buddy was hanging out with me and he told me that I was overexposing the test shots we were shooting. He said that especially with HD cameras it's better to err toward an underexposure because it really brings out the colors in the image. This is something I've been trying to achieve on all my shoots since I got the camera. But now I'm starting to question this logic.

Maybe it's because I'm using CINE 4 Gamma and he's has no experience with CINE Gamma. I dunno....

What gamma setting do you shoot with and do you err toward overexposure or underexposure? (Yeah, I know, perfect exposure is what we're really shooting for)

Also, I've been shooting with the Doug's (Vortex Media) Picture Profile. He recommends Black and Black Gamma to be set to -2. Maybe that's another reason my stuff looks a little muddy. Dunno...

[Mike Chandler]

Hi Mitchell:
It is better to err towards underexposure, because once that highlight is gone, it's gone. It's not like shooting digital SLR RAW, where you want it to be as high as you can go. Although this probably belongs in a different thread, here are my PP settings. When I used this setting, the picture through my eyes was identical to the picture on the monitor. Anything else I felt was best left to post.

Matrix
On Standard
Level 0
Phase -5
RG +75
RB 0
GR -18
GB -18
BR 0
BG 0

Color Correct Off
White Off
Detail On
Skin Tone Detail Off
Knee
Setting On
Auto Knee On
Point 90
Slope )
Knee Sat 50
Gamma
Level 0
STD4
Black -
Black Gamma 0
Low Key Sat 0

[Doug Jensen]

Originally Posted by Mike Chandler

Hi Mitchell:
It is better to err towards underexposure

I disagree. Depends on what your're shooting and how much post-production processing that you want to do. I stand behind my statement that is is better to err on the side of overexposure, but that's assuming you're talking about only a 1/2 or 1 stop. If it's more than that, you've got to stop and ask yourself what you're doing wrong.

In general, if you have most of the shot looking good but you still have a part of the picture that is overexposed it is going to be a bright cloud, a background window, reflections on water or chrome, etc. It is better to let those things blow out than to bring the entire exposure down and get muddy blacks all around. Muddy shadows is what ruins the picture more than some extreme blown out hightlights. Even in high-end feature films you often see blown-out hightlights. It is not the end of the world and is better than underexposing the rest of the scene.

Obvioulsy, the ideal thing is to get your exposure dead-on in the first place. Why err either direction? Getting the right exposure within 1/2 to 1 stop isn't so hard if you use the zebras properly (not at 70) and have a little experience with the camera.

Doug