Lens Flare

What is lens flare? The geek zone will tell you it is the refracted or scattering of light from within the lens elements. Even the best lenses have flare, it is just very well controlled by the quality and treatment of the elements within the lens.

The closer in alignment with a light source, the greater the possibility of flare and zoom lenses with more elements are more susceptible to flare than prime lenses.. Glare is a good example as it is most definitely a result of lens flare. As glare goes it is a broad refraction of light that causes the glare. Often a curves adjustment on Photoshop can do wonders with mild glare.

Below is a shot I took last week of the sunset in Leland Michigan. A nice composition that is lost by the flare of the sun. There is a specific reason for this flare that I will get into shortly. Needless to say this is not an example of great photography.

In discussing lens fare in a training presentation I am putting together, I have used two images that demonstrate lens flare. The first image on the left is not only a flare condition but also glare. With lenses you do get what you pay for. The image on the left is actually from a closed circuit camera with a very inexpensive lens. On the right flare is still evident even on a high end lens. In this case it was a Canon EF 28-104 f/4 L USM lens. But is this the fault of the lens?

Zoomed in you can notice a slight halo of light around the sun, this is balanced flare that is acceptable. The flare or second sun in the 7 o'clock position from the sun is not a result of the Canon lens at all. Rather it is the reflection on the UV filter screwed on the front of the lens. Actually I had a circular polarizer on the front of the UV filter as well.

The diagram above shows how lens flare is generated by use of filters in front of the manufacturers glass. The further from a center aligned light source, the greater the flare effect as well as glare.

Solution: There are a number of ways to mitigate lens flare. First is to not shoot into the sun or bright light but that is often unpractical. Second is to use quality glass. The third and what I should have done in the first image above is to remove any screw-on filters from the front of the lens.

I support the position of a coated daylight or UV filter for normal shooting to protect the front element of an expensive lens, but I should have removed it for that series of shots.

Hey, that does it for me today. Take care... Doug