Lens flare is a fact of life and it can often show up on your pictures unannounced. All three of the lenses in this review have special coatings that are designed to reduce lens flare. The more elements a lens has the greater the chance of unwanted flare. Flare is generally caused by bright light just outside the image area. The best defense for lens flare is to use those lens hoods that are shipped with the lens. The Pentax D FA 50mm includes a lens hood but we did not use it on this test to ensure all the lenses were evaluated equally.
For this flare test we placed the sun just outside the view image and worked to create flare in the image.
Although all three lenses had significant flare, the “winner” was the Pentax DA 50mm F1.8, the runner up was the Pentax D FA 50mm F2.8 Macro. The Pentax FA 50mm had slightly more flare than the D FA 50mm. The amount of flare did not improve as the lenses were stopped down, in fact it got worse. The best way to avoid a lens flare from ruining your pictures is to remember: if you have to shield your eyes from a source, then it would be wise to shield the lens as well.