>>...have you seen any filter caused imperfections on my >>images already posted? > >It's impossible to know, Dimitri, if none of your posted >28-300mm images were taken without a filter. Without >something to compare against - as Eric and Brian have already >mentioned - we can't say whether the generally low contrast is >due to a filter or some other cause. > Generally true, but, as I said, I am testing every filter, very long, under any light. In case I see ANY imperfection caused by filter, back it goes. Most of my images posted before are off-camera JPEG, without any PP. Not now, D800 files are so easy and great to PP, so everything now from me is JPEG converted from RAW in PP. Any filter im my use is not causing any low contrast or any other problem. Dimitri.