Typo, it should read 70%

I'm a little curious about using 70% (or whatever setting you prefer) for gauging the correct exposure for skintones. Given the plethora of complexions, how can you settle on anything?

It can't!!!!
I've been trying to tell people this for years. Pick any three people at random on a New York street and I'll show you how 70% can't be right for all (or maybe any) of them.

A calibrated gray card of known reflectance value or something bright white are the only two reliable targets for zebra.

Thanks. I thought I was the only one who thought that this was a little nutty. The palm of the hand is about the only part that seems to have any uniformity. But grey card.....yes.

OK, I will come clean on this. Generally I have my Zebra 1 set to 70+, depending on subject matter I may vary this up or down by 10%, as Doug says no two skin tones are alike. I also use the LCD viewfinder to judge the overall exposure, but this does require you to set up the screen accurately. I use the Colour (Color) bars for setting up the display, and may check this a couple or more times during a shoot – the contrast and brightness buttons may get moved especially if you fumble to turn up peaking etc. Shame Sony couldn’t have incorporated a lock on these. I also occasionally use the Histogram, just to check that shadows or highlights have not been totally lost.

My background is as a stills photographer and I spent many years studying and using the Ansel Adams Zone system of exposure. This has helped me to understand which areas to take a reading from and how to interpret that reading. It’s surprising how many photographers will shoot a snow scene and wonder why the snow looks grey. Of course the Zone system also relies on developing the film to compensate for high or low contrast scenes etc. This is something that can’t be easily translated to digital capture, although I am working on it.

In short I use a combination of Zebra, Histogram, eye balls and experience to judge exposure, and generally I get it right to within ½ stop most of the time, any small variation can be corrected it in my NLE.

If you want a good fail safe method, then set your Zebra to 98% and then set the aperture so the lines on highlight areas just vanish, this should produce the correct exposure but keep an eye on the dark areas making sure they don’t block up. Or as suggested use a Kodak 18% grey card (available from most good pro dealers)

Agreed, this has to be the best method these days as NLEs have such good grading controls that as long as you preserve your highlights and ideally use gamma and knee settings to maximise dynamic range you'll have the most information in the picture to work with. The only exception is quick turnaround news-type stuff where they will be no time for grading, in this case you want to get a pretty picture straight out of the camera.

Steve

Thanks Vincent for the tip, I find it very difficult getting used to the EX3 viewfinder and also in getting it set with the brightness/contrast controls.

I've recorded with clips under exposed and some slightly over exposed. I'm going to try that and see how that goes.

Thanks again.

Strange behaviour of zebra1: sometimes I get zebra1 stripes not all the way to zebra2, therefore leaving an area between the two with no stripes at all. I thought it should cover everything from e.g. 70% to 100%, where zebra2 takes over.

It's a normal behaviour - see http://www.dvinfo.net/conf/1179015-post9.html

When you use the zebra for exposure you are usually running and gunning - shooting very fast with no monitor. As a rough guide so my exposures are safe I put my zebra @ 60%, and look to see it on caucasian faces. If I'm shooting darker people I may lower it.

Its not science nor is it exact, its just a way to save your ass in a rough and tumble situation. It works and has been used by video shooters for many many years.
In SD we usually set it at 70. Many find 60 better for HD.

OK, thanks, Piotr.

Leonard,
With 60% zebras are you looking for highlights on the face or all over the face?

Wherever I would expect to see a solid flesh tone, depending on the lighting and the situation. Certainly not all over the face.

Like I said before its not a science. People on this forum really overthink a lot of exposure and color balance issues IMHO. If I have time I always have a monitor I know with a waveform and I trust that to get me very close. I do care a great deal about accurate color and exposure.

However, If I'm in run and gun territory then I just want to make sure I have an exposure and color balance that's close enough. Running 2 zebras at 100 and at 60 or so is a big help. So is balancing off any piece of white paper or napkin or cloth you can find. Personally I favor computer printer paper- don't ask me why as its not all the same. I also carry a little swatch book of gels to cheat if I have mixed light or something looks green on my viewfinder. Its never failed me and I think what I'm describing is typical of professional shooters.