Thanks everyone for the advice.
I have been shooting B&W 4x5 and sometimes I do shift the lens.
I'm excited to try a wider lens than I have now, thanx for the help!
The shorter the lens, the more likely one is working at the edges of its coverage. And the closer to the edge, the greater the falloff. Super Angulons and lenses of similar design are about as good as it gets in an approximately symmetrical design--their apertures appear round (if they appear at all) even at the extremes of coverage. But the light is spread over more film because of the acute angle. Only a strong retrofocus design--not done in conventional view camera lenses--can correct that issue. The view camera lenses provide superb sharpness and lack of distortion in return.
I routinely use a center filter with my 65mm Super Angulon when using 4x5. But I do not use one on my 90 or 121, neither of which I usually use at their limits of coverage.
Rick "still hoping to find a dirt-cheap center filter for the 47 someday" Denney
Years ago a co-worker tried to convince me about a software product he found that could "interpolate" digital data that was never there. He claimed the thing could understand and "restore" the image of a bird perched on a limb even though only six pixels represented the bird.
Hey... if it ain't there... it ain't there. Just do the right thing whether that's digital or analog. Like a beautiful lady... everything between the toes and the shoulders is great. Everything beyond that is just a headache and a losing battle!!