In article , ottawa97@emr1.NRCan.gc.ca says...
>: > I use a Nikon FM and have lenses at 28, 50, and 105 mm. I
>: > would like to buy a 20 or 24 but couldn't decide which one
>: > will suite me better. If anyone in this group would share
>: > his or her experience, I would very appreciate.

>The 20 will "fit" well with your present lens line-up BUT if you're into
>filters, you'll be in for an expensive surprise. For the 20/2.8 you
>might have to invest in the costly 62mm "wide" polarizer (regular
>polarizer will vignette) and buy a whole second set of filters for
>that lens (assuming your systemized for 52 thread). The shade isn't
>cheap either.
>Both the 24f2.8 and 20f2.8 are optically superb.

I go along with the general recommendation of the 20 over the 24,
and note that with best samples of both Nikkor f2.8's, the 20 is
a little better than the 24 optically. I find no need for a
shade with the 20mm (a hand to block the sun when it is just
outside the picture area is sometimes useful), unlike the 24mm
which is more sensitive to out-of-picture side light. Also,
regarding a comment above, if you do like polarizers, you may
not like them on a 20 - polarization is VERY uneven over the
angle-of-view of a 20mm lens. I would avoid wide-angle zooms,
if you care about fine image quality - none but maybe the huge
and expensive Nikkor 20-35mm comes near the fine performance of
the Nikkor 20mm. Use it from f5.6 to f16, and you will be
amazed how good a wide-angle lens can be - it is first-rate.
Hope This Helps