less bad than Nikkor lens are. Go for Tamron or Sigma if you dont like your
Canon "consumer-grade" zoom.

 It's very tough to find truly objective, non-biased lens reviews.  I'd say
that at least 3/4 of the lens reviews that I read fall into one of a few
categories:

1.  It costs less than a few thousand dollars, it can't be worth anything.
2.  It's from brand (X), it can't be worth anything.
3.  I found a shortcoming or two, it can't be worth anything.

 What so many people fail to realize is that lens design is about
compromises - you simply cannot design and build a lens that is perfect in
every aspect.  Whether you're talking about Canon, Nikon, Leica, Zeiss, or
any other lens manufacturer, you'll find that they've made lenses designed
with certain goals in mind that would disappoint someone with different
objectives.

  Many reviewers also fail to take into account the fact that normal people
don't have 4-, 5-, or 6-figure budgets for lenses.  I've seen a lot of
reviewers make the assertion that if you can't drop at least three grand on
a lens, you shouldn't bother with *any* lens, or trying to take the picture
at all.  That's just rubbish.  Between getting a modest picture with a $300
lens and getting no picture at all, I'd *usually* rather get the modest
picture.  If you don't play the game, you can't win.

 I'd strongly suggest "The Lens Book" from Hicks and Schultz, ISBN
0715301497.  It doesn't appear to be in print, but you can either pick one
up used, or even get it from the library.  It'll help you understand quite a
bit about different aspects of a lens, and picking a lens that meets your
needs.  It covers all of the questions you've put forth in good detail, and
a whole lot more that haven't even occured to you yet. : )

steve

Here is a shot taken with a Canon 75-300 IS at full zoom.
http://home.comcast.net/~charlesschuler/wsb/media/291308/site1046.jpg

Tests are one thing; real photography is another.  Beware of the lens snobs.

The build quality of this lens is fine; given its cost.

Speaking directly to the 75-300mm lens, regardless of manufacturer, these lenses
are all 'good to very good' from 75 to about 200mm (sharp, contrasty) and they
are pretty soft, not to mention slow, from about 200 to 300mm.

A good 'hint' about lens quality is the zoom ratio.  Above 2.5:1 zoom ratio,
don't hold your breath on quality.

Given the crop factor of the Canon D60, I would consider both a long prime along
with a 1.4 TC to attain fairly good quality for nature shots rather than a
softish at the long end lens like a 75-300.

Think about, perhaps, the 200 f/2.8 and eventually add a 1.TC.

Or maybe the 100-300 in lieu of the 75-300.

You cannot correct for lack of lens sharpness (or poor focusing) in photoshop.
You can enhance the photo using USM, but it won't recover for the 'blur' created
by the lens.

More generally speaking, a careful bit of shopping with the right inputs will
lead you to the better priced gems.  Avoid high ratio zooms.  Avoid what sounds
to good to be true.  One exception for Canon: the 28-135 IS lens gives very good
performance for the price, from what I hear and some images that I've seen.

The build quality should be appopriate to the use.  If you will banging around
trails in all kinds of weather, a poorly built lens will not last long.

I use to have lovely, cheap Minolta lens that was sharp a tack, if a mite slow.
(70-210 var-app).  It was well, if cheaply built.  I would never consider using
it on a long trip in the woods, or in dusty areas.  Sold it for a good price too.

Cheers,
Alan

Most zoom lenses fall off when they get to extremes of focal length
regardless of price or rating.  One of the things you pay for in more
expensive lenses is larger apertures and a bit more sharpness.  And those
costs can go way up, but it's often worth it, especially if you want to
shoot at low ISO values.  As for build quality, I can only go back to my
"old" days of taking photos.  Usually, the lenses manufactured by Nikon,
Canon, etc., hold up pretty well compared to "off-brand" lenses.  Good pro
lenses made by the big guys may outlast you.  What happens with cheaper
lenses is that they start to loosen up after awhile, and it just gets worse
from there.  Some of my older Nikon lenses are built like tanks and have
lasted 30 years.  They use a lot of plastic in some of today's lenses, so
who knows?  And pros tend to thrash their equipment around quite a bit, so
the better stuff is made to take it.  Pros can't afford to keep all their
equipment in their individual cases and pad everything up.  They need to get
to stuff fast, and may have two or three cameras hanging around their neck
wacking into each other as they work.  When I worked for AP a lot of the
guys kept their equipment in the trunk of their cars with no cases.  The
stuff just rattled around in there (the trunk was their gadget bag).  And,
the equipment help up extremely well.  Not sure if today's plastic would
take that much punishment.

Another thing is that generally speaking, and IMHO, fixed length lenses are
going to be sharper than zoom lenses, so the tradeoff is carrying a pile of
lenses around, and having to change them all the time, or compromising with
a zoom.  Remember also that you can "process" your images a bit to improve
your images using software.