The zoom range of the 28-200mm lens is an amazingly convenient, but at
a cost of some image clarity. The images below
demonstrate the trade-off between convenience and image
quality between using my Tamron 28-200mm super zoom lens (f3.8-5.6) and
my Nikkor 85mm fixed focal length lens (f1.8). Camera: Nikon D70.
Click on an image for the original, full-resolution jpeg version.
I have taken thousands of good pictures using the 28-200mm super zoom
lens on my Nikon N90s (film) camera over the past several years,
including many photos that I would
have otherwise missed entirely due to not having the right lens either
with me or on the camera when the opportunity arose. I do use the
Nikkor 85mm f1.8 lens for special occasions (particularly portraits),
and I love it. But for casual use, when I only want to carry one
lens (on the camera), I have used the 28-200mm zoom.
Digital Camera 1.5x
Focal Length Multiplier Affects Clarity?
Because the image sensor in the D70 is smaller than 35mm film size, the
camera effectively multiplies the focal length of the lens by
1.5x. This means that my 28-200mm zoom lens acts like a 42-300mm
zoom on my D70. You probably knew this already. However, I
believe this also means that any
fuzziness caused by the lens is effectively multiplied by 1.5x!
[Someone please correct me if I'm
wrong in drawing this conclusion!] Therefore, depending on
your personal priorities for convenience versus clarity, it is
conceivable that you may judge the image quality of the 28-200mm zoom
lens to be "good enough" on a film camera, but not "good enough" on a
digital camera with a 1.5x focal length multiplier. Of course,
this is a matter of personal priorities and judgement, and I'm afraid I
have not used my D70 long enough (just a few weeks so far) to reach my
own conclusion on this.
