I was reading a review on luminous-landscape earlier testing the new Canon EF 400 F4 IS DO. The person testing it did a good job. I was impressed with the results. Then I went to the Canon web site and read this....... Note: If a very bright spotlight like a mercury lamp is photographed with a DO lens, a ring of light may occasionally appear around the light source, due to the imaging characteristics of the multi-layer diffractive optical element. how does this problem affect landscape pictures and pictures near the angle of the sun? Can this lens be used to photography sunsets? This sort of makes me wonder about the rumor of the 500mm F2.8 DO IS? Are we getting a good lens replaced with a bad one? Guess only time will tell.