As photographers, we try to obtain the highest quality images that we can. Of course, it is not the pure technical quality of an image that makes it a succesful one, as there needs to be a compelling subject as well. All other things being equal though, we would all like to obtain the best quality image of any given subject that we can. So we try to keep our equipment clean and protect the exposed front element of our lenses one way or another. If we buy used equipment we look very carefully for any scratches etc that might be on our new lens.
Now, I am not implying that we shouldn’t be doing any of the above to try to ensure that we obtain the best image quality possible. But did you ever wonder how much scratches or dirt on the front element really effect image quality? Well, have a look at Kurt Munger’s Dirty Lens article here and find out.
I do wonder how much more might be found if the images presented were inspected more enlarged or printed large and if the effect might be more obvious if the lens in question were a higher quality one but, nonetheless, the answer seems to be that these imperfections of the front element do far less than one might think!
Along the same subject line here is an interesting, if not a bit absurd (with a bit of humor ) article by Roger Cicala of LensRentals.com on shooting through filters entitled “Good Times With Bad Filters”.