Learning to light with a light meter

[natxbrotha]

I have been wanting to learn to light with a meter for some time now and I think I'm ready to take the plunge, but I have some questions before I purchase one and get started. I'm shooting with the Canon 5D Mark II and plan to possibly get a 7D in the future. I do primarily weddings and narrative short film stuff.

• What light meter are you using?
• Are light meters camera specific (i.e., film vs digital)?
• What meter do you recommend?
• How/where did you learn to light with a meter?
• Can you post any links to good learning tutorials/workshops/classes that are offered?
• Do you have any tips/tricks you have learned in the field?

Thanks for any help and/or insight you can provide! I'm ready to start getting my ratios better!

 

[PerroneFord]

Hmmm...

I have a SpectraCine IV

A film specific light meter will work fine for video

The SpectraCine IV is a fine starter meter or less expensive option, the Sekonic Cine line do much more and are worth it if you will be using it often.

I came from film, where metering was essential.

I don't know of any tutorials. A basic understanding of lighting is helpful, and a knowledge of F-Stops is critical. Any photography book will sort that out. I typically meter the darkest areas of the scene to see if they are going to read cleanly on the camera, then the brightest areas to see if we are going to blow out, or if we are out of dynamic range of the sensors, then I read the faces.

Any tips? Sure, dozens. But get the meter first and learn to use it. Then come back and ask for tips.

 

[natxbrotha]

How would I know what the darkest and brightest points are on my camera before they clip or crush? Do I need to know what the lowest lux/footcandle my camera can handles at a certain iso/shutter/aperture before I can determine this?

What is exposing to the right?

 

[Barry_Green]

How would I know what the darkest and brightest points are on my camera before they clip or crush?

You can't. Not unless you do extensive testing to learn exactly how your camera performs under any given settings configuration. And if you change the settings, throw that out the window.

Which is why you should be using a waveform monitor for that kind of info. A light meter can't tell you that.

Unless you want to invest in something like the Sekonic 758DR, which lets you actually program in your digital camera's characteristics so it knows exactly how the camera will perform. But it's a whole lot easier to just use the waveform, especially now that many cameras (HPX170/HPX300/HMC150/HMC40) and monitors (BT-LH80 on up) all have waveforms built into them.

Do I need to know what the lowest lux/footcandle my camera can handles at a certain iso/shutter/aperture before I can determine this?

Yes, but you'd also have to test it at each iris setting, each gamma curve, etc.

What is exposing to the right?

A term from using a histogram. Histograms show the brightness distributed across a graph from left to right; when shooting digital you want to expose in the brighter range as much as possible without clipping. When you do so, the histogram slides to the right, hence "exposing to the right".

 

[PerroneFord]

When you light your scene look at where the shadows and dark areas are. Look through the lens if you need to. Determine what the darkest areas are that need to have detail preserved, and meter those spots. Then look at the brightest spots in the frame. If there is a practical on in the frame, meter that as it SHOULD be the brightest thing, so meter that.

No, you don't need to know what the lowest lux/footcandle your camera can handle. You need to understand the dynamic range of the camera, and then follow the chart for making a correct exposure. Then determine how far above and below center your camera can handle.

Print out this chart:
http://www.panavision.co.nz/main/kbase/reference/tbleExposure.asp

Light your scene so that you get those readings on the exposed side of the face or key subject. If your camera can handle 6 stops, then make sure anything you don't want blown out is no more than 3 stops more than this, and anything you don't want crushed is no more than 3 stops below this.

I believe the 7D has about 7 stops of latitude so three up and three down from correctly exposed should put you right in the game.

I have no idea what "exposing to the right" means.

 

[PerroneFord]

A term from using a histogram. Histograms show the brightness distributed across a graph from left to right; when shooting digital you want to expose in the brighter range as much as possible without clipping. When you do so, the histogram slides to the right, hence "exposing to the right".

Awesome, I learned something.

Barry, it seems we meet rather often on these light-meter threads!


Natxbrotha, Light meters aren't magic tools. Can you light your scenes with them exclusively? Yes. Does it require doing your homework? You bet! Is it easier to use a waveform monitor and see where your values are falling? Yes. Is a histogram helpful? Yes.

Barry is certainly correct, that if you are going to use a light meter exclusively, you had BETTER know your camera. So keep a small notebook handy, then light and take notes.

When we did the 5D shoot last month, I restricted the camera to ISO 320 and ISO 100 so I'd have some idea of what was happening. We shot tests, I adjusted, and we shot the movie. But I would never, EVER, shoot with just a light meter if I hadn't done the tests first. You'll come back with garbage more often than not.

 

[Barry_Green]

I believe the 7D has about 7 stops of latitude so three up and three down from correctly exposed should put you right in the game.

But you can't count on it without testing, because frequently with video cameras you'll have maybe 1.5 stops of overexposure headroom, and 4.5 stops under...

Again, you gotta test test test.

Or get a calibratable monitor with a waveform, calibrate it for the prevailing lighting conditions, then light so it looks good and check the waveform for trouble spots, and go.

 

[Barry_Green]

Awesome, I learned something.

Glad to help.

Digita video characteristics are usually pretty common -- when you get deep into the shadows, you get blocky murky ugly noise. So if you want the best overall image, on a scene that isn't stressing your camera's dynamic range, you're better off overlighting it, shifting the whole histogram as far to the right as you possibly can (note: WITHOUT CLIPPING, of course!) That way you're using the cleanest, nicest part of the exposure curve.

You can always adjust back down in post to bring it to "appropriate" brightness levels for the mood of the scene. But if you can lift your scene out of the murky gutter and record it clean, then your final graded scene will look that much better.

Hence, why in digital, you'll frequently hear people advise you to expose to the right.

If you're going for the ideal look in-camera, then "expose to the right" doesn't necessarily make sense. But if you're going to be doing color grading in post, you should aim for exposing to the right whenever you can. (again, as long as it doesn't compromise the image in other ways; if you run the risk of clipping highlights, or you have to boost gain to get the image over to the right, then those are bad choices).