About exposure, white balance and smartphones.

Yes I tend to talk a lot about smartphone cameras, and for good reasons. First, we always have them with us and they got to a point when they provide decent quality even if you print the photo with a 18×15 cm or kinda A4 size. Which is more than enough for most of us. Second, I hate elitist crap about how the camera brand X is better than Y, mirrorless is better or worse than dslr, feature Z is needed otherwise your camera suck, that lens is 2% sharper in the corners than the competitor, etc etc. I have no interest about such nonsense, life is too busy and short to waste it debating tech details. I prefer to spend it living and taking photos in the meantime. So, modern smartphones are a good candidate for receiving great joy taking photos, and I care about how to get better photos out of them.

Exposure.

Smartphones tend to over-expose. They are programmed to show the scene as close as possible to a “standard” brightness level. Their software and metering systems are trying to take almost any scene and show it to you as if it was shot in a sort of daylight, we could say. So a dark moody scene could become a much brighter one.

That’s why it is important to lower the exposure so that it matches amount of light in the scene. By doing so we will capture a scene that is faithful to what we are actually experiencing.  Lowering the exposure to match reality will also make the ISO go down, which means the noise reduction will be less aggressive and the dynamic range will expand since we will bring the sensor closer to its base ISO. Everyone will be happy.

The advent of HDR and its variants also meant a further disrespect for the actual light in the scene. Don’t believe the hype from the phone makers: their new incredible HDR system is not going to always capture a faithful reproduction of reality. It will mix different exposures, bump up colors, remove noise (and details), and all for giving you an image that seems to have captured what you saw. It is an illusion, a blend of technology and marketing that wants to convince you that your tiny camera phone sensor can do much more than what physics allows it.

The photo on the left was shot with an iPhone 6s on full auto: the phone decided to apply HDR. The one in the center was shot manually lowering the exposure: the exposure met the real scene but the colors in the sky were all wrong. The photo on the right was shot using Procamera and changing white temperature and tint so that the photo matched the real amazing colors of the scene. So we have a full auto interpretation of the phone software on the left, which is wrong, and a faithful capture of reality on the right. By the way, the photo on the right also had less noise and artifacts.

Someone could argue that on the left we have much more detail on the field and trees while on the others we have very dark areas. Years of full auto and HDR gave us the illusion that a good photograph must show detail everywhere. Right at the end of that sunset, the sun was hiding behind low dense clouds and distant hills and the field looked dark. When we take a photo we must accept compromises. Our eyes adapt “exposure” in real time to what we are focusing on, so we have the perception that everything is “exposed correctly”. A camera has to balance exposure for managing to capture what the real scene was like. In this case, the scene was dark, contrasty and with strong colors, with the field details barely visible. Notice that we could still use an app to slightly brighten the field since the lower ISO gives us more dynamic range. And the result would still be much better than the creepy full auto HDR.

White balance.

Let’s move to another topic that is of huge importance in digital photography and that we also see represented in the sample photos: white balance. How many times did you see a beautiful light coming from the windows or at sunset, but your photo showed nothing of that magic? Well there’s an answer for that, and it is mostly about white balance.

Truth is, you don’t need a white that is always absolute white. The white balance could represent the real scene or the way we experience the scene. A sunset will modify the light temperature in the scene: if I neutralize this trying to get a pure white on the walls, I am basically removing the sunset.

It usually makes no sense to use automatic white balance: you need to think about the scene, about what you want to show and how — about what you feel when you look at the light. Just like with the exposure, our smartphones and digital cameras read reality and capture it averaging everything to standards decided by their designers. Which is not good. In the scene from the sample photos, the sky had a glorious deep purple color, but the iPhone turned it into a bleak warm pink.

If you let it do its business in auto, a smartphone will read a scene and will try to understand what is white according to some shade of gray it is calibrated to; it will then change the white balance for the scene. In this way we very likely lose the real light in our scene — but we all know light can be warmer, colder or have some color, and it all contributes to the scene we see and experience: changing the white balance is important.

It is also important to set the proper white balance while shooting, without relying on the fact that raw files let us change it later. If we set the correct white balance while shooting, we can make sure we are capturing the scene as we intend it, as we live it. Who knows what we will remember about that scene after days, weeks, months! With the advent of “smarter” cameras that are supposed to manage all kind of situations, the photographer is very often turning into a dumb button pushing entity. A photographer is much more than this. A photographer is first of all a mind; a photograph is the way a photographer captured light. We can’t let the cameras do the thinking for us. So it is important to capture the scenes as we live them, with the white balance we decide to follow or subvert.

My advice is to always capture both a jpg and a raw if your camera or app allows it: this way you can record a jpg with the white balance set as you want, and then also a raw that you can edit later if you want, using the jpg as a reference. We tend to trust our memory too much, a little reference is also good. This is the way I shoot with both the iPhone and the Ricoh GR II.

White balance can also be used for creative purposes, by exploiting its inherent issues. For instance: in this photo I mixed artificial and natural light, which had very different temperatures and tints. By balancing them I got the background wall (lit by an overcast natural light) to become blue, while the inside architecture was lit by artificial warmer light, creating an interesting chromatic contrast. This simple example should make a point: white balance is a tool and we can use it in a way that fullfills our vision. We can capture reality as it is or we can alter it to capture it not as it is, but as we are. Do you really want to let an auto setting do this for you?

Conclusion.

You may object that shooting always jpg+dng will fill your phone with countless copies that are not really needed. And you would be right. In our daily shooting we basically capture two kinds of photos: the ones with expressive quality, the ones without it. If we take a photo of a recipe so that we can remember it later, that is not expressive. If we take a photo of light and shadows creating arabesques on a wall, that is expressive. Ok that might be an extreme simplification, but you get the point. My advice is use the standard phone camera for capturing random stuff, when the expressive quality of the photo is not relevant — but for everything else do yourself a favor and use a camera that allows you changing exposure and white balance (temperature and tint). I use Procamera on iPhone, but there are many other choices.

What I wrote applies to both smartphones and digital cameras, since the reasoning is the same. The marketing language is usually different, but the reality stays the same.

Be the mind. See the light, understand it. Be the one that creates the photograph, don’t let you camera do that for you. It will get it wrong, because a camera has no mind, it is just a tool.