The only thing about the 18-70 that may disappoint is that the close
focus distance is only about 38cm / 15 inches.
I do macro, and have a 105mm macro lens, but also I have experimented
with the 18-70 with one extension tube, 13mm length.
That takes the focusing distance at 70mm from about 38cm through to just
under 1:1 ratio.  The results are not bad at all.
A problem may be that it is difficult to buy just one tube, as they
usually come in sets of three with about 13mm the smallest.  The longer
tubes are not of much practical use with the 18-70, and neither is the
13mm with the 18-70 zoomed out less than about 50mm.  Tubes are
available with the electronic contacts, which are needed if metering is
going to work.  Despite using this combination several times with a D70,
I assumed that the AF would not work.  Today I forgot to switch AF off,
and it works even though the extension tubes say very clearly on the box
"Manual Focus Only" (it doesn't work very well unless the light is
good). When they made the extension tubes perhaps they didn't think
about "fly by wire" AF-S lenses.  I think that one extension tube of
13mm may be more use/better than diopter adapters with this lens.  It
has a large front element and filter ring, and good quality adapters
will be about as expensive as extension tubes.  Perhaps more relevent is
that lighting for macro is often tricky - most dedicated macro lenses
have front elements that are recessed in to the front of the lens,
almost like a built-in lenshood.  When I was playing with the 18-70 and
extension tube today outdoors, it was difficult to eliminate flare from
the sun reflected in windows etc.  Adding up to three layers of extra
glass by way of close-up adapters will make this problem worse.
So, that is in my opinion a good cheap solution.  The 18-70 is a
terrific lens for almost all I do.  I have a macro lens which is for
sure better (sharper, less distortion, easier to use, longer focal
length), but it was quite expensive (A Nikkor 105mm AF macro lens will
cost nearly as much as the D50), and the 18-70 with a tube does nearly
as good a job in many cases.  For portraits, the 18-70 is good, but a
wider aperture fixed focal length 50mm f1.4, or the inexpensive f1.8 may
offer some advantage, but perhaps you would need to be quite serious
about things to consider it worthwhile.  There is one advantage that the
D70s may have over the D50 for macro work - a DOF preview button.  DOF
is very shallow, and shooting macro is when I most use this feature, as
it can be very hard to guess the effect of aperture on how background
objects will be rendered.

The 18-70 AF-S zoom is a good lens. Not very good, but good. It's autofocus
is not too precise, so with wide open aperture at 50 to 70mm focal length,
the AF-S of this lens tends to back focus. I think it has a bit of a lag
when it locks in focus that tends to overshoot the target. It's very cheaply
made. The lens hood is junk. I have already lost it once and had to get a
replacement for $10. But for a D50, it will be good enough.

The 50mm f1.8D AF is one of Nikon's best optical performer. It's also build
like a piece of junk made out of plastic. But it sells dirt cheap ($99). Its
optical performance is excellent and its AF works well.

The 70-300 f4-5.6D AF ED zoom is a good lens. Again its build like Nikon
wants it to self-destruct in no time to ensure that we always have to buy
new lenses. The AF is sluggish. But on a D70, between 70 to 200mm I get good
results.

The 105mm micro Nikkor f2.8D AF is a very good lens. It's actually a very
useful lens, which is also build well. It focus from infinity to 1:1 and is
well worth the $600 (US dollars!).

The 80-200mm f2.8D AF is a very good lens. It's heavy and an overkill for a
D50. But it's sharp and has a good AF. Even for a D70, it's a little bit too
heavy. But hey, we're all waiting for the D200 ;-)

How about Sigma and Tamron lenses? Well, find out for yourself.

Gregor

A good place to get information about lenses is the forums at
dpreview.com. There is lots of detailed talk about lenses, and lots of
example pictures taken with various lenses.

A candidate for a "general purpose lens" that was recently discussed
there is the Nikon 28-200. Not the best possible lens, but good bang for
the buck.

Bob B.

On Thu, 25 Aug 2005 18:26:08 -0700, furtherside wrote:

I've found this to be a good general purpose lens for my D70, and it is
the lens that I usually leave attached to the camera.  Its not as long as
the old 28-200 (tamron) I used to leave attached to my 6006, but its
lighter, faster, and focuses quicklier.  (Also, the 28mm on the D70 is not
at all wide angle, which is a killer indoors)

Anyways, if you're looking at purchasing the D50 body and adding this
lens, I'd suggest getting the D70 kit which comes with this lens.  With
the $100 rebate on the D70 kit (not the D70s), you could get the D70kit
for about the same price (or less) than the D50 body + this lens.