Understanding Histogram and How to Expose to the Right

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There aren’t many guides about the histogram and how to correctly “expose to the right” out there so I will attempt to make a clear and easy to understand guide about using histograms when shooting pictures or videos.

histogram how to use it and how to expose to the rightWe have all confronted the sun glare when using mobile phones or tablets outside in nature. You can’t clearly see what’s on the screen. So when flying a drone it is often hard to decide whether you have the right exposure or not.

Even if you can see the screen well, it can be on full brightness or dimmed, so you will almost never get an accurate preview.

That’s why you can’t say for certain if the exposure is correct, and that’s why there is a histogram option available in most drone apps.


What is a histogram?


how to use histogramThis is one example of the histogram. The left side represents dark parts of the image, middle represents mid-tones, and the right side represents the bright parts of the image.

At first glance, you can see that this image was on the darker side, with some mid-tones,  and just a bit of highlights. And that is correct as you can see from the image below.

histogram how to use it and how to expose to the right

As you can see upper-left part is where highlights are. Mid-tones are upper-right and in the water reflection of the sky, and everything else is dark.


The height of the curve represents the number of pixels in the image for that particular tone in the histogram. So if the image is darker, the curve will be very high on the left side. And if the image is bright (for example snow shots) histogram curve will be low on the left but high on the right.

histogramYou can see for the image above, the curve of the histogram is peaks on the left side of the histogram, and by the looks of it, the amount inside this red line takes about 1/2 of the whole histogram, and the image confirms it.

So to recap:

Left to Right – from pitch black to completely white
Bottom to the top – the amount of that tone in the picture.


Now we know what the histogram is! So let’s start learning How to use histogram for the best drone picture and video exposure.

The problem with this is that most commercial drones nowadays don’t have big DSLR camera sensors. Smaller drone camera sensors mean that less light falls onto the sensor surface. Less light means that pixels on the sensor get less information. This is the reason why we often have a lot of noise in our images.

For example, you know how your phone takes great pictures during the day when there is a lot of light, but it takes lousy photos full of noise during the night?

Low light and more noise on the left, and more light with less noise on the right.

The same thing happens with drones’ cameras. You want to put as much light as you can through the lens! (but not too much or you will clip the image, we will explain that later)

All I said above is the reason we want to expose to the right.


How to expose to the right?


When we look at our histogram we want to expose so the curved line moves to the right. But pay attention to not go too far because you will clip the image.

What is image clipping?

Clipping occurs when you expose too much or too little. You are then only left with pixels of the image that don’t contain any other info than being completely black (0) or white (255).

In the histogram that is shown as a big spike on the far left (for black) and far right (for white).

histogram example
As you can see, the big spike on the right (white) side of the histogram tells us that something (and a lot of it) is overexposed.

So we want to set it to something like this:

histogram how to use it and how to expose to the right
You want to expose so the curve in the histogram goes as far as it can to the right without making a spike on the pure white (255) part.

This way, if you want a darker image you can edit it in post and darken it to your preference while keeping the quality and detail. And if you were to expose for a darker image at the start, you would be stuck with that noise.

Same goes for videos.


Final look?


And in the end you should be left with a pretty nice image like this one:


NOTE: This guide should serve as a tip and you should see it as a guideline. And you could follow it in order to get a better image or footage in most situations. It is by no means the only and ultimate guide that guarantees best in the world pictures and videos. Photography and videography are art forms. And you should create content, not just follow instructions and do whatever they tell you to do. BE FLEXIBLE! You might even surprise yourselves.


Here is another example taken and edited by a professional photographer Przemek Maliszewski, using the Expose to the right technique. This was captured with his DJI Mavic Pro Platinum drone in vertical/portrait mode at sunset.

f/2.2, ISO 100, Focal length: 4,73mm, Shutter speed: 1/610s

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