Modern lens coatings are often so good, it’s difficult to introduce natural lens flare into your shot, even when pointing the lens directly into the sun.
It’s easy to over-do it, but a little fake flare can sometimes turn a ho-hum shot into something a bit more interesting. The image above of the Nā Pali coast in Kauai was shot with an AF Nikkor 14mm f/2.8D, and even when pointed directly at the sun, the lens produced very little flare. Fake dust and simulated anamorphic optical flare was added in Brainfever Media’s LensFlare Studio. While Adobe Photoshop includes a basic flare generator, here’s two stand-alone apps for OS X which offer far more options and adjustments. While LensFlare Studio offers more adjustments (including stackable filters), Ohanaware’s Shine can produce some nice organic effects. At these prices, you can afford to try both: