The Sun Flare

Who doesn't love a good sun flare in a photo? They can transform a boring image into something artistic and warm. Maybe even a bit more dramatic. Have you ever tried to take an image to purposefully create one? How did that go? Let's dig in and hopefully learn something to make it a tool that you can use in your own photography. Or maybe it will be something you will be able to more successfully avoid.

What IS a sun flare?

A sun flare is just a lens flare created by the sun. So we should really ask what a lens flare is. It is an effect that occurs when too much light enters the lens and subsequently scatters around inside the lens before reaching the sensor. A perfect lens would transmit all 100% of the incident light to the sensor. In reality, some of that light will go where it is not supposed to. See the diagram below. That scattered light will show up as either a series of bright spots (repeated images of the light source) or by making the image look washed out. Typically, lens manufacturers use precision optics and apply special coatings to the glass in the lens to try to reduce flares because they tend to reduce the image quality. Nevertheless, the most expensive lenses will still be subject to flares.

Are flares good or bad?

A flare could make an image more interesting or it could ruin it. That determination, like a lot of things in art and photography, is a matter of the viewer's personal preference. Because you have no control over what other people think when they view your work, the best you can do is to be intentional about how you set up your photograph. A good photographer takes control of the available light to realize their artistic vision. In other words, if you are taking the picture, the flare is only bad if you did not want it there.

Controlling The Flare

To be intentional about whether you create a flare, you need to understand in what situations they occur and when they don't. With that understanding, you will be able to either use them to your advantage or avoid them.

How to Avoid Flares

Typically, I try to avoid flares because they lead to unpredictable results, which takes longer to get the shot. If you don't want a flare, the number one rule is to not point your camera straight at the sun. If you are pointing your lens in a direction where there is the possibility of extra light coming into it from the side, you can use a lens hood. If you don't have a lens hood, you can get creative. Use whatever you have available to block the sun or extra light from entering the lens directly. Oftentimes, you hand is the most available tool available for the job. Lo-tech solutions can be just as effective as commercial solutions.

How to Create Flares

If on the other hand you want a flare, don't take one shot and expect it to lead to the best results. Rather, take multiple shots and change your angle with respect to the sun and the subject so that you get different looking flares to choose from in the resulting images. A fun fact is that you can change the effect of the flare in the image by changing the aperture on the lens. A large aperture (i.e. Low F-Stop number like F2.8), will let a lot of light through and provide a smoother flare. If you close down the aperture (i.e. choose a higher F-Stop) the flare will become more star-like. The star shape is the result of the shape of the aperture.

To be more illustrative, I performed an experiment with an off-camera flash to show how the aperture size affects the shape of the flare while maintaining a constant exposure. To do so, I kept the shutter speed at 1/200 and then successively took images with the aperture size decreasing by 2. To compensate for the smaller aperture, I increased the ISO by 2. Check out how the shape of the flare changes.

Fake the Flare

If you want maximum control, you can always fake it. It is not hard to add a fake flare when post processing an image. Software like Adobe Photoshop and Gimp make this easy. Simply add a new layer with the image of the flare and you are done. If you are working on a phone, check out apps like Lens Distortions or Lens Flare. These make it trivial to not add that little bit of extra drama to your image.

Above All Have Fun

Now that you know more about sun flares, go play with your newfound knowledge and create some awesome images! If you liked this post, then share it with your friends as well.