Ryan E. Walters, Cinematographer

Cinematic Excellence at 24 Frames a Second

How To Use Custom Sekonic Profiles


As you may already be aware, I have put together a lot of training on how to use a light meter and have compiled an extensive list of camera profiles to use with the Sekonic 758 & 478. And it appears that I incorrectly assumed that it was clear on how to use the profiles once they were loaded into the meter. (at least from the emails I have received recently). So if you have been sitting there wondering, "Okay, now what do I do?", this blog post will explain how to use the custom Sekonic profiles I have created.


Understanding The Profile In The Software-
Before we take a look at the meter and talk about how to use it in the field, it is important to launch the DTS Software and take a look at the custom profile. Below is a screen shot of the C100 profile I created for Log mode using the 758.
Screen Shot of C100 Profile - Edit Mode in the DTS software

The first thing to pay attention to in this profile is the outer two red arrows and bars. These bars represent the maximum dynamic range values for over and under exposure. There is no more information past these points. If you do not agree with these readings, all you have to do is click and drag the arrows to change them to the readings you agree with.

The second thing to pay attention to is the green arrows and bars. They represent where the image begins to show some clipping. I think it is unfortunate that the DTS software uses the phrase clipping point, as the image isn't really clipped- at least not in the way we are used to thinking with digital images. Instead, it is better to think of the green arrows as representing where the image starts to show signs of clipping.

I use the green arrows to mark where I want the roll off into absolute white and into absolute black to begin. By being more conservative with these values, I can get smoother transitions (especially into white) than if I just worry about the absolute values.


The next thing to pay attention to is the 0 line. This is mid tone, and by looking at where the red arrows fall in relation to the 0 line you can tell how many stops of over and under exposure are available in the camera you are shooting with.

The last important thing to be aware of is the purple line. This line represents the curve of the camera- how it responds to light, and how gracefully, or how sharp it rolls off into the highlights and shadows. A steeper curve results in a harsher transition, and a more digital looking image. A more graceful and less steep transition results in a less digital, and more "filmic" looking image. (If you want to see why the Alexa image is so sexy, take a look at how it handles over exposure- it rolls off gently & smoothly ...).

Understanding The Profile On The Meter-
Now that you have a basic understanding of what the profile is telling you and how the camera performs, it is time to put that knowledge to practical use. Below is a reading I took using the incident mode on the 758 & 478 using a profile I created for the 5D MKIII shooting in RAW with the Magic Lantern Hack.
Reading taken using the 5D MKIII RAW Profile I created.

Now if we take a look at the 758  we can see 5 small little arrows on the bottom of the screen that look rather familiar. These arrows are the same ones that appear in the DTS Profile. The outer arrows are the red arrows, and the inner arrows are the green arrows. And the center mark is mid tone.

758 Reading & Dynamic Range Display
Taking a look at the 478 we see a similar display. However, instead of small arrows we see a colored representation of the same readings. Where the dark red begins is the same point as the red arrow in the DTS software; where the light red begins is the same point as the green arrow in the DTS software. And the small line in the green area is the mid point. (Due to the limited scale on the 478 and the low light reading, we cannot see the underexposure range on this particular example).

478 Reading & Dynamic Range Display
Using The Profile-
With a firm understanding of what the profile and meter are displaying, it is now time to put that information to use. By setting the mid tone to this reading (press the mid tone button on the 758, and use the wrench icon in the 478) you can lock in the mid tone reading to the meter. Now I recommend flipping into spot mode and taking readings of the scene. Each reading you take will show up as a new mark on the scale.

By using the spot meter to take reading of important items in the frame, you can get an exact reading of where that object will fall on the exposure range of the camera system you are using. So, for example, say you wanted to know if a highlight was going to clip or not, you would take a spot reading and see where it falls on the scale. If it is outside of the range indicated on the meter, then you know it will clip. The same is true for underexposure.


The real power in having this information isn't just knowing that a part of your image is clipped into white, or crushed into black, but it is in knowing exactly where it falls. If you had an important highlight that you did not want to clip, and you took a reading and it was 1 stop outside your range, you now have two options available to you. You can bring up the overall ambience level by one stop, or you can knock down that highlight by one stop. You don't have to guess. And not guessing means you save time on set, and communicate more efficiently to your crew. (Even if that crew is only you- it will save you from making multiple adjustments).

And that is all there is to using a custom profile created for the Sekonic meters. It is the power of custom profiles that keeps me tied to my meter over the other more convenient options like iPhone apps.

Have you been using the profiles on your shoots? Do you have any other recommendations or tips you recommend for how to use the profiles?

Until Next Time - Get Out There And Shoot!

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