Correct exposure with PD170

[Phil Kay]

I've gone from using my PD170 in full auto to full manual (focus and exposure). I've cracked the manual focus bit, but am having real trouble with getting the exposure right.
In a nutshell - what looks ok in the screen or in the finder doesn't look right on a TV or computer screen.

How do I know when I have the correct exposure? Say I'm filming an interview and I want the skin tones to be correct, how do I know that they are by looking in the viewfinder?

Keep it simple,PLEASE! :0)

[Mike Rehmus]

The LCD screen never will look 'right'. Forget it as it is only, at best, a framing tool.

The viewfinder can tell you focus and exposure rather accurately. Use Zebras to set the exposure (search this forum, lots of advice about using that feature). The resolution of the finder is just enough to set focus accurately in most situations.

If you want to make color decisions in the field (a question you didn't ask, I know), you are going to have to haul along a color monitor capable of displaying accurate color. It has to be calibrated as does your studio monitor. Forget the computer monitor, it is unlikely to be able to display video accurately in any case. The camera is incapable of reproducing the colors in most scenes anyway.

So, number one, learn to use and trust the zebra indicator for exposure. The only alternative to that is to haul along a waveform monitor and that isn't for everyone.

So it is simple, just not easy.

One other bit . . . the LCD and viewfinder in these Sony cameras do not show the entire frame. For that you do need an external monitor with underscan.

[Pete Wilie]

Here's my approach for setting exposure.

In the studio/home before you leave for shoot:

1. Obtain an electronic copy of the SMPTE color bars in JPG format.
2. Copy to PD170 Memory Stick
3. Display color bars from PD170 MS on external monitor (or TV if you don't have monitor)
4. Calibrate the Monitor
5. Calibrate the PD170 LCD to match the monitor

Now your PD170 LCD is not going to show perfect exposure, but it can be used in the field if that's all you got.

In the field (without a monitor):

1. Establish lighting
2. White balance
3. Zoom in on the main object of interest. If a person, then this will be their face.
4. Turn the PD170 zebras on, and set to 70%
5. Set manual shutter = 60, and gain = 0
6. Adjust iris to obtain zebras on the "hot spots" of the face (nose, cheeks) -- this is for white Caucasian faces. If face is darker, open iris a little more.
7. Switch zebras to 100% to see if anything else is blown out. If so, and it's important, close down the iris a little. Sometimes you will have to accept the background being blown out to get proper exposure of your subject.
8. But try to avoid high contrast lighting, like sun/shade.

If the shot is critical and there is high contrast or difficult lighting, shoot it three times bracketing the exposure: best guess, 1 stop under, 1 stop over. When in doubt, underexpose. You can always add brightness in post, but if the image is overexposed too much, the video information is lost and can't be recovered in post.

Mainly, experiment a lot using the above as a guide. When you display the footage on the monitor/TV, be sure to turn on the Data Code that shows the exposure settings. Do this enough and you will develop a feel for setting exposure.

Of course, it's best if you can have a monitor with you in the field. But some times this isn't practical.

Good luck, and practice, practice, practice. :-)

[Phil Kay]

Thanks guys, that's very helpful. I'll go out now and experiment.

[Bob Harotunian]

Pete mentioned white balance. From my experience there is not much more important to accurate color reproduction than a good manual white balance. Otherwise, experiment with using the LCD as a guide and slight underexposure definately produces a better image for us with the PD170.
Bob