Digital BW, The Print

Sharp-cut filters (when shooting in color OR black & white) definitely improve image sharpness because they eliminates chromatic aberrations that blur images and produce colored fringes. 

Better quality filters which make spectral cuts more sharply work better than lower quality filters. 

Green filters usually work better than red or blue since most lenses are corrected chromatically for green. Apochromatic lenses are the exception. 

Randy Bresee
www.RandallRBreseePhoto.com


--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Paul" <roark.paul@...> wrote:

> My conversion process almost always uses a "split channels" step.  This results in 3 B&W images, each filtered with either a red, green or blue filter. With very good lenses, these should be perfectly aligned already, but with a lens that fringes badly, they won't be.  
> 
> I have not tried this, but these could be made into layers and then the "Edit > Auto-Align Layers" routine used.  This just might eliminate the fringing.  I suspect the layers could then also be re-assembled for color work as well as simply making sharper B&W images.
> 
> Paul
> www.PaulRoark.com