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How to Correctly Set Exposure on a Canon EOS DSLR Using the Prolost Flat Picture Style

In this video I explain how to set exposure correctly on a Canon EOS DSLR while using the Prolost Flat picture style.

You can find more details about the Prolost Flat picture style here:

Getting Started

To start, in your camera settings, navigate to your picture styles, and go to User Defined 1. From there, hit info to set the details and set the picture style to Neutral. Once on Neutral, set the Sharpness all the way to the left so that it is at 0. Do the same for contrast. Dial the saturation two clicks to the left and put color tone on 0.

While you’re in the menus, set your color space to sRGB. It doesn’t make sense to use any other color space since the video being recorded is Rec.709, which is even less colors than sRGB.

Also, change your Histogram display to Brightness instead of RGB.

Now that that’s done, lets start with how to figure out what your exposure is.

How to Read Your Exposure

When you have your Canon DSLR camera in video mode (or live view mode) push the “Info.” button until the brightness histogram is displayed on the screen. Look at it closely. You should see that it is broken up into 5 zones with a vertical line separating each zone.

The zone on the far left is blacks, the zone on the far right is whites, and when looking at a Luminance waveform in Adobe Premiere Pro (or your editor of choice), this Brightness histogram directly corresponds to the IRE levels you would see in a waveform display, so something all the way over to the left is IRE 0, and something all the way over to the right is IRE 100. The camera’s histogram divides it up into nice 20 IRE chunks for our ease of use. The very middle of the middle zone is IRE 50.

Canon DSLRs shoot full swing video and not studio swing (Google those terms if you don’t know what that is), so what you see in the Brightness histogram is literally IRE 0-100. Pretty nifty to know, and very easy to verify. Just shoot some footage, make note of where it is on the Histogram on the camera, and then look to see where it is on the waveform display in the editor.

The histogram is not perfect, but it is waaaay better than nothing, or even worse, trying to set exposure using the display on the back of the camera. Not a good way to go. Use the Brightness histogram. It’s the fastest way to get consistent exposure from shot to shot.

Other Tools You Need

So now that we know how to tell what our exposure is when we’re using Prolost Flat, how do we set our exposure correctly?

Well, you need a couple more tools, but don’t worry, they’re very in-expensive. Ideally (and the best case scenario) is you would have an 18% grey card. I use Mennon 18% grey cards, but really, any card will do as long as it an 18% grey card. A couple of things to note: A white balance card is not an 18% grey exposure card. Do not confuse the two. An 18% grey card is for setting exposure, and a white balance card is for setting white balance.

If you don’t have that, you can also use a normal sheet of white copy paper to set exposure. Either one will work.

Setting Your Exposure

So, to set your exposure, you set your lights up the way you like, and then you place the grey card (or white sheet of paper) where your skin tones would be (or human faces) and have it directly facing the camera. If your shot doesn’t have people in it, then place it where it will be lit by the primary source of light in your scene. From there, change the exposure controls (ISO, shutter speed, aperture) on your camera (or add/remove light) so that the grey card or white sheet of paper sits in the right spot on the histogram.

It’s that simple.

The Correct Exposure Settings

So what is the right spot on the Histogram? This is the money part of this post:

The 18% grey card should sit as close to 40 IRE as possible. It should cause a spike on the histogram right on the line separating the 20-40 IRE zone and the 40-60 IRE zone.

The white sheet of paper should cause a spike at 70 IRE, which is right smack in the middle of the 60-80 IRE zone. Remember, this is reflected flat white and not specular highlights or light sources which are brighter than white, so a basic reflected white should be 70 IRE straight out of the camera when using the Prolost Flat picture style.

White is a funny thing, which is why I recommend actually using a grey card over a white card. It’s a lot easier to get consistent exposure with a grey card.

That is it. That is how you set exposure on your Canon EOS DSLR Camera using the Prolost Flat picture style. It really is that easy. It will give you a fairly usable image straight out of the camera that will be really easy to grade and go from pretty usable to looking really great with a little color grading, and you can get the same look and cut footage from multiple Canon DSLR cameras super easy this way.