Take three or four exposures of the same scene. Don’t change anything on the camera and keep the framing the same.
Learning About The Histogram:
A histogram is essentially a bar graph that uses the exposure data built into the photographs metadata to calculate the exposure values. So, from the image above you can see that this image would be exposed well with a lot of detail in the shadows and highlights.
This is a great thing to remember then using a histogram, I think they’re an excellent tool If you’re wanting to improve your photographs from a more technical point of view. The RGB values in the graph above act the same way as the shadows and highlights but for colour. As you can see on the image above, reading the histogram would suggest that there’s not a lot of data for the shadows, but it’s a little bit more active in the blue channel.
Is it fundamental?
The short answer is yes, but there’s lighting conditions and scenarios in which you may not use it. For example when you’re shooting a sunset, you’re shooting white sheep, you’ve got products against a black background, you’ve got a backlit subject – these are all examples in which you probably wouldn’t be too fussed about what the histogram is saying.
Luckily with the introduction of .RAW files along with the introduction of fully mirrorless sensors, able to capture immense amounts of dynamic range – you’ve got flexibility. For example, if your highlights are blown out by about 1-3 stops you may be able to salvage that data but for a file like this:
But you may be able to refine sunsets for example, here’s an example of a photo that I’ve taken with quite an interesting histogram reading:
This is the histogram from the base image:
As you can see, I underexposed this photograph quite a bit, this is an effect that has become quite popular amongst mirrorless photographers with flexible raw files. You have more freedom when it comes to post-processing. In this particular case, by underexposing I’m cutting a lot of the white out of the sky. By doing this, I have more flexibility for cloud adjustments in post. All of that black data contributes to the image. But, even if I wanted to boost the shadows up that wouldn’t be an issue either, as you can see from the histogram, the blue channel is very active in the shadows, but black values aren’t completely underexposed, I would still be able to lift the images highlights up further if I wanted to achieve a different effect.
Why do we do this?
Taking full advantage of your camera’s capabilities isn’t wrong and it never should be. Since the early days of photography, photographs have been manipulated, doctored and adjusted after. People have been ‘pushing’ 35mm film beyond its capabilities for decades. A lot of our favourite shots have used this technique.
After taking my camera out to the local park, I immediately started looking for the perfect setting for this experiment. I decided to settle on a little rubbish bin sat on the edge of a verge which overlooks the city as I needed a place that would offer the biggest insights into minute changes captured on a histogram. I usually tend to focus a lot of my editing sessions starring endlessly at the histogram in order to perfect/refine any inconsistencies in a captured image so this should be quite interesting. I think the main thing I learned from this is to not over edit my pictures in post If they don’t need it, I do spend a large amount of time colour grading and colour correcting but it’s quite interesting to see how much the work the camera actually does itself.
The main thing I realised about my camera’s automatic settings is that they’re actually not too bad. I mean, if you look at the highlight cut off points throughout all of the images they’re really consistent. The shutter calculation is part of the reason, It’s quite hard for a lot of cameras to work out overcast sky levels without bringing the image’s exposure completely down – in these 3 cases they estimated really well. Looking further, there’s not a lot to say about the highlights, I think you could probably boost them up a bit, for a camera? I think it’s perfectly suitable if you’re on the fly.