How do you judge exposure for video on a GH3 without Zebras or False Colors?

For me at least, the first step to judging proper exposure is adjusting the monitor screen brightness to match the ambient light. On my Panny TM900, I would use -1 for nighttime, 0 for normally lit interior shots, +1 when taking pictures on bright overcast days and +2 for working in sunshine. At the moment, I'm trying to figure out which monitor settings work best with the GH3. There are many more increments, the changes are more subtle, and the screen doesn't seem to get as bright as on the TM900, though I haven't done any side-by-side comparisons. From my first tests though, it appears that the camera meter tends to overexpose by around 2/3 stop. Ideally, if the screen is calibrated correctly, when correct exposure is achieved, the image on the monitor should look neither too bright nor too dark. Since I've never seen this brought up before, can I assume most people don't change screen brightness according to the situation?
 
The GH series doesn't have a good "calibration reference" to do this and be any more accurate in "judging" exposure. Yes I might brighten the screen or EVF for use in bright sunlight but I would still have to pay attention to the meter and perhaps use the histogram to supplement judgement.

The Canons do give a reference, the adjust monitor brightness screen brings up the last still image shot and shows a B&W "stepped" gray scale alongside. You adjust LCD brightness until you can see ALL steps on the grayscale from the deepest black to the pure white, and at the same time see the full tonal range in the last still.

You have me thinking about this so the next time I'm out with my GH3 I'll see what difference adjusting EVF (that's what I use most) brightness will make. You do have to insure you set it back to midpoint for "normal" use, though.
 
Bruce - My only experience with video up until a couple weeks ago has been with using the Panny TM900, and although the LCD monitor was crap, I could rely on it (along with the meter, etc.) for proper exposure. That is, when the scene was correctly exposed, the image in the monitor matched the values of the clip, provided I used the settings I mentioned above. It appears that with the GH3 monitor that isn't going to be possibe. Whatever brightness level I set it at, the monitor looks dark when the image is correctly exposed. And for most scenes, I find that the camera's built-in meter reads 2/3 stop to a full stop over. So I've begun using the EVF for all of my shooting. It looks as though I'll be picking up an external monitor at some point in the future...
 
I've mostly had luck exposing the GH cameras, but dearly miss proper exposure tools such as waveform, zebras, & false color.

Even the most skilled eyes, or even external meters, do not match the precision of those tools.
 
which meter mode? how to expose for skin tones?

which meter mode? how to expose for skin tones?

Can anyone advise on which metering to use, and an exposure or histogram interpretation for proper skin tone exposure?

I typically use the center or spot meter and usually get good results when the histogram turns white and my exposure indicator suggests proper exposure. I also have the highlight overexposure indicator enabled.

Every once in a while I get over exposed shots when my histogram looks good, my exposure reading looks good and highlight indicator is absent. Some times the images are just a bit flash and washed out, but other times the base exposure is acceptable but I have blown out highlights. I'm either using the wrong metering, misreading or putting too much faith in the camera's indicators.

Is the spot meter best for evaluating skin tones and areas with problematic highlights?

Any suggestions would be appreciated.
 
davidp158 said:
Can anyone advise on which metering to use, and an exposure or histogram interpretation for proper skin tone exposure?
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A histogram is going to do very little to help you "interpret" exposure for proper skin tone exposure. A histogram gives you a visual representation of where your image tones, light and dark, fall over about a 5 stop range. Proper skin tone exposure is probably best achieved with spot metering although there are other methods such as incident meter readings.
davidp158 said:
I typically use the center or spot meter and usually get good results when the histogram turns white and my exposure indicator suggests proper exposure. I also have the highlight overexposure indicator enabled.
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If skin tones are your most important tones to set exposure for, center or spot will usually do the trick. The histogram, exposure meter readout, and highlight overexposure indicator will tell you "other things" about overall exposure.

davidp158 said:
Every once in a while I get over exposed shots when my histogram looks good, my exposure reading looks good and highlight indicator is absent. Some times the images are just a bit flash and washed out, but other times the base exposure is acceptable but I have blown out highlights. I'm either using the wrong metering, misreading or putting too much faith in the camera's indicators.
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Actually, none of the above. What is missing is a good basic grounding in photographic exposure. There is always a very specific range of tones that any given exposure will render correctly. In some cases everything you need falls neatly into that range but in some other cases lighting contrast will exceed that range and the only way to deal with it is to limit the light falling on the areas where the highlights get overexposed or "blown" by using diffusers or light blocking panels, or by moving the subject out of the way of the stronger light that is causing the problem.

davidp158 said:
Is the spot meter best for evaluating skin tones and areas with problematic highlights?
Click to expand...

If skin tones are the most important thing to expose for I use either spot or center weighted metering but I also do a quick test to see what else is happening in the image then try to reposition something to solve any problems that occur. This is where a good solid understanding of lighting and exposure and how those relate to each other comes into play.
 
Bruce - Thanks for taking time to respond.

Can you recommend a resource (book, web tutorial, or exercise) that will inform me of that "basic grounding of exposure"? I could invest in a meter that does incident measurements, but without that "basic grounding…" I won't know how to make use of it.
 
Here's a fair "start". Even if you think you already know what's in this article, read it through and see the way he ties points together.

http://photo.tutsplus.com/tutorials...-ultimate-beginners-introduction-to-exposure/

Then do a search for "photographic exposure", some of the articles will be very informative, some will not. But taken all together they should help you "get a feel" for it. Meters will usually tend to read and set exposure for the brighter areas so if you stay aware of this you will better be able to interpret meter readings.

An incident meter ignores all of that and reads light falling on the meter (why we usually take an incident reading from the subject position) and sets overall exposure for an "average" subject based on the light falling on that subject. But don't run out and buy an incident meter. I find the metering system in our Canon's and GH series cameras to be more than accurate enough.

We just need to learn how to interpret them.

Good luck
 
Bruce - Thanks for the link and info. Much appreciated!

I have read a few photography books, and thought I had basic grasp on exposure, but my inconsistent results suggest I need to study this further.
 
davidp158 said:
Bruce - Thanks for the link and info. Much appreciated!

I have read a few photography books, and thought I had basic grasp on exposure, but my inconsistent results suggest I need to study this further.
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Basically you probably need to study some and then apply what you learn. It's hard to try to explain how that's done but I, like many others, learned something about exposure in a time when most cameras did not have even a simple "match needle" system. I started with the data sheet that came with film, used the table printed on it (memorized it for Tri-X film). It was based on the "sunny 16" rule (sun over your shoulder, f16 and shutter speed equal to the ASA/ISO rating on the film and adjust accordingly for cloudy overcast and other situations), from there I bought a simple reflected light meter and then cameras started coming out with meters.

Color slide film, especially Kodachrome, was probably the greatest enforcer of exposure discipline. You learned the film and how it behaved because you made your exposure and then had to wait a week or two to find out if you were "on" or not. Now we have the LCD and EVF to give us some instant feedback on our exposure and this is a GOOD thing.

The eye sees a very broad dynamic range of tonal values but the LCD will only show you about an 8 stop range at most, the histogram shows a graphical display of a 5 stop range and reflective print media will show only a bit more than that. Your job is to train your eye to "see" in terms of exposure, and right now your difficulty may simply be that your expectations of what you can "squeeze" into that image in the way of tonal values may be a bit high.

Dive into it, shoot a lot and study what you're getting. Try to acquire "discipline" in how you approach exposure.

It will come.
 
davidp158 said:
Bruce - Thanks for taking time to respond.

Can you recommend a resource (book, web tutorial, or exercise) that will inform me of that "basic grounding of exposure"? I could invest in a meter that does incident measurements, but without that "basic grounding…" I won't know how to make use of it.
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There's a reason why exposure meters became popular after their invention... because The Eye is so untrustworthy... Zebras and the like will only set the high and low depending on the type... they will not indicate 'placement' of the tone of what's in the middle...

A waveform monitor would be much better, but unfortunately is not available in the GH-1/2/3. One would need some external equipment for that...

In any case the spot meter is probably the most useful tool to set specific exposure of specific scene elements, absent the waveform monitor. Plus the spot meter can be carried around for location scouting, where taking test shots with the waveform monitor would be cumbersome for many situations.

An incident meter will allow one to know the amount of light falling on a scene, but not show the relative reflectivities that may be important in placing the scene values, or compensating for a wide dynamic range of the scene.

However, it needs to be understood that the light meter produces a meter reading for a specific 'gray' value. (Color meter is different from a general 'light meter'...).

That 'grey' value is approximately for an 18% grey result in a photographic process. This 18% is approximately at the 50 IRE but cameras vary on this, depending on the manufacturer. Recently I tested my Nikon D600 on an 18% grey card, and the 'outof the box' value when viewed on a IRE display seems to be about 45 IRE.

What does that mean... well at 18% the 'grey' card represents a 'mediterranean complexion', and so for dark complexion the meter is giving an exposure indication that will allow 'too much' light in, about 1 stop too much, whereas for a far north 'translucent' complexion, the meter is reading too low, and about 1 stop under.

There are many variations of skin tone, but these are sort of general principles.

So, the metering would be:

Meter the face of the person, and

1) Open up 1 stop if the person is fair to 'very fair'.
2) Close down one stop if the person has a dark complexion.

This also means that one needs to change lighting schemes for dark and light complexion.

Similar considerations are required for inanimate or non-human species, where the value of the subject will set what is required for adjusting from the meter reading for camera settings.

This is where 'dynamic range' comes into play, and why there will be compromises...
 
Reading off Caucasian skin tones and opening one stop was an "emergency" kind of reading if we forgot our incident meter. In many cases that simulated an incident reading. I used to read off the back of my hand (under the same light falling on the subject) then open that one stop.

Yes, an incident reading takes nothing about the various reflective values and tonal values in the scene into consideration, but it did do a very good job of arriving at an exposure that would allow the various elements in the scene to "register" on film at their respective values.

But David is at a point where in his best interests we need to simplify things for him and fortunately most of our cameras have a tool for doing just that.

The LCD or EVF. He can do the "spot" reading (with his GH camera meter set to that mode) then make an exposure and see what it looks like. He does have to accomplish two things first: Familiarize himself with what a "good" exposure looks like in the EVF or on the LCD, and have some method of shielding one of those from bright daylight if outdoors. I can shield the EVF with my hand close the camera and my face, and I often carry a Hoodman Hoodloupe with a 3X eyepiece in the bag or with the neck lanyard that allows it to hang within reach.

The eye may be unreliable at first but it can be trained. I've trained mine and have found the GH2/GH3 EVF to be a very good tool.

We have 3 "tools" to evaluate exposure: The meter readout at the bottom of the viewfinder screen (EVF or LCD), the appearance of the image (either in the EVF or with a loupe on the LCD), and the histogram (once one learns how to interpret a histogram). I use all three (and it's much better than having to wait a week or two like in the Kodachrome days!!!).

I don't use it much but I still have the Sekonic L28c incident meter (copy of the old Norwood Director Hollywood used to depend on) I bought myself in the BX air terminal shop during a stopover on Okinawa on the way back from VietNam in 1970. Sort of as a "congratulatory" gift for having made it through a combat tour. I dug it out a couple weeks ago and shot some tests, the metering system in my GH3 came very very close to identical exposures. I really could have used either method.
 
Bruce - Thanks for taking time to respond.

I viewed the link you suggested, and feel I already have a good grasp on those fundamentals. I just want to be able to dial in skin tones more consistently, and was wondering if there is a technique specific to that using the camera's built in metering. I was hoping there would be a way to anticipate what exposure zones fall within the histogram display, as I don't have an external monitor with false color info. A friend just gave me his old Minolta IVF meter, which may help my exposure learning curve.

Regarding your comment about camera histograms only displaying about a 5 stop range, does the histogram clip off, or inaccurately display, the shadow and highlight extremes?

BTW, I really appreciate not having to wait for film to be developed!
 
davidp158 said:
Bruce - Thanks for taking time to respond.

I viewed the link you suggested, and feel I already have a good grasp on those fundamentals. I just want to be able to dial in skin tones more consistently, and was wondering if there is a technique specific to that using the camera's built in metering.
Click to expand...

Most of the time spot or center weighted will do that for you if you control the area those modes read. In a portrait (or video scene that is a closeup like a portrait) skin tones are everything and like j1clark posted skin tones are variable. But you have to have a starting point so after doing the reading take a test shot at the settings the reading suggested and see what it looks like. Adjust up or down as necessary to get what you want.

davidp158 said:
I was hoping there would be a way to anticipate what exposure zones fall within the histogram display, as I don't have an external monitor with false color info. A friend just gave me his old Minolta IVF meter, which may help my exposure learning curve.
Click to expand...

As you gain experience you'll be able to do that better. Remember, the histogram is NOT an exposure meter, it's a guide that needs to be interpreted in relation to what your eye sees as image tones in the scene.

Minolta made some fine meters. That one should help you (I just checked and it still goes for $195 to $219 used), I've seen it in use by others.

davidp158 said:
Regarding your comment about camera histograms only displaying about a 5 stop range, does the histogram clip off, or inaccurately display, the shadow and highlight extremes?
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It "clips" mainly if your exposure is going to "clip", and it doesn't inaccurately display. What it will do depends entirely on the range of tonal values in any given scene. With a scene that is largely snow overall it may easily clip on the right side or it may merely "crowd" the right side. If you have lit one person with one light that has a carefully controlled beam and most of the background goes dark to black the histogram display will "crowd" the left end of the display or even clip some. In either case you may have very little in the way of graphic "spikes".

A histogram is what it is. Take a lot of test shots and compare what the image looks like with the histogram display that can be shown with stills. You can learn a LOT by doing that.


davidp158 said:
BTW, I really appreciate not having to wait for film to be developed!
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Me too. No way do I want to go back to "wet process" photography. I had a lot of fun in my home darkroom, I got a lot of satisfaction out of what I could do on the job but I DO NOT MISS the cleanup. The Ektachome processor we had at the base photo lab filled up a room and usually took me a day to a day and a half to pull the racks, scrub them absolutley clean, mix fresh chemistry, and put it all together. The day the photo maint crew crated it up to ship it off (when we converted to digital) I literally jumped for joy.

The day the lab chief told me to process no more B&W he expected an argument. I did handsprings when he walked out of the studio. Again, a lot less cleanup and I don't miss scrubbing out stainless steel tanks.
 
Bruce - Thanks again for your help and insight. I'll get there, but have to put in the time to learn the fine details.

BTW, I used to work in pre-print shops, and had to deal with film processing and maintaining the processors. Don't miss that one bit.
 
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