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Garrett Low January 31st, 2011 06:43 PM

What do you use to set exposure?
 
Another question for you 7D shooters. As I stated in another post I will be shooting a movie and the director wants to use a 7D. I'm trying to undergo a crash course on the camera. I'm hoping to get some hands on time soon but for now I'm just trying to get a handle on what control and features are available on the camera.

What do you use to set the exposure for your scenes? I'm use to having various tools at my disposal to set exposure. I like using a combination of Zebras, one set at 70% and the other at 100%, then I check my Histogram for overall exposure balance. On the 7D it does have a histograms which will help but I generally like to see know when I'm hitting 70% on faces. Can anyone tell me what the exposure level indicator is telling me when it is say in the middle? Is this equivalent to say 70 IRE?

I've downloaded the manual and poured through it but there are a lot of things left out for shooting actual movies.

Thanks again,
Garrett

Gabe Spangler January 31st, 2011 08:11 PM

I've always exposed to my eye with the aid of the histogram or zebras. I like to know when something is clipping, but otherwise I have my camera lcd and my external monitor calibrated to be super accurate – what I see is what I get. I don't pump the brightness of my monitor, hence underexposing the footage, which a lot of people run into because they want to be blinded by their monitors (foolish). A monitor should be accurate, not contrasty or bright. When I get the footage onto my calibrated computer monitor, the exposure is almost always exactly what I was seeing on the camera.

There is no rule as to how bright or dark a scene should be. It's all subjective. Lighting subjects' faces to 56 IRE or whatever will get you uniform, boring footage, which is good if you are working in corporate video, but bad if you are working in feature films or in a more creative arena of film/video production.

So ... if my exposure comes out to, say, an f4.0 in a scene and I want to be at f2.8 for depth of field purposes, then I drop in a 0.3 (1 f-stop) ND filter and I'm right there. So generally I am choosing the f-stop beforehand and then controlling the light into the camera to be properly exposed to that f-stop. Like if you are outside on a sunny day you can use the "sunny 16 rule," which states that you will be properly exposed if you set your f-stop to f16 and your shutter speed is equal to your asa rating. But what if you want to shoot your outdoor scene at f8 or f5.6 or f4? You can work off that f16 base and figure out how much ND you will need to open your iris and slow your shutter to the proper 1/50, if that's the shutter speed you want. And then of course you may want a slightly dark, underexposed look or a crispy bright look, so you adjust for that as well.

I always want to be between about f2 and f11, depending on the lens. F16 is too deep for the aliasing and codec on the 7D, in my opinion. And too wide open produces muddy and soft images, generally. But maybe that's what you want. Who knows....

But of course none of this flies with film. But I'm a video baby, I don't care. Never shot film, probably never will. I'd love to, but unless someone gives me $100K, it ain't happening.

Liam Hall February 1st, 2011 07:09 AM

Remember this is a stills camera.

The exposure meter will tell you where 18% gray is at and whilst there're no Zebra on the 7D, you can check the histogram to see what is clipping.

An incident light meter can be useful at times, but the best thing you can buy is an external monitor that has scopes built in. There are a few on the market that have histograms, waveforms, false colors and a range of other overlays to help you.

You shouldn't trust any monitor that doesn't have these aids, even if it's calibrated - you certainly shouldn't trust the LCD on the camera.

Garrett Low February 1st, 2011 04:44 PM

Thanks Liam. I very rarely rely on what I see in the monitor for exposure or color settings, and yes I do calibrate my monitors. Unfortunately I won't be using my equipment for a lot of this shoot as it will be provided by the producer and director. I could request a quality monitor with proper overlays but I don't think it will become a reality for this project as budgetary constraints will not permit it. I've never shot with a 7D before so it will be an interesting experience. I'll be doing some test shots with it tomorrow so I'll be getting a good idea of what to look for when setting exposure.

Bill Pryor February 4th, 2011 11:21 AM

Just remember that the in-camera meter is a reflective meter and therefore it can lie to you under some circumstances. For example, if the scene is very dark, then it will say it needs more light when maybe you really don't want to open up. You can take a reflective reading off the skin tones, off the dark areas, etc., and then choose the exposure you want. You can also, as suggested, use an incident meter.

Brian Tori February 5th, 2011 09:44 AM

While it is nice to have a monitor with scopes in the field, this is not always possible due to budget constraints or lack of power etc... I always light assuming I will not have these to use that way I'm prepared for the worst case scenario. My suggestion is to invest in a incident/reflected lightmeter. You can take an incident reading for the levels falling on the scene to get consistent results and then use the reflected reading to measure points of light that are high in the exposure range to keep then within limits. Depending on the overexposure range of the particular camera, this could be 2-4 stops above exposure. The way to test this is to take a series of test videos and bring them into an NLE to test the exposure range of the camera. If you do not have a lightmeter the alternative method is to get a 18% gray card and use the built-in meter to take readings from the camera position.


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