Is a Nikkor 18-70 a noticeable step up from a 18-55 G II kit lens?

RichA wrote:
On May 5, 3:31 pm, "Neil Harrington" wrote:
"per" wrote in message

...

Hi,
I've got a Nikon D40 with the kit 18-55 and the new 55-200VR.
I found my 55-200 to be considerably sharper than the 18-55 GII. I've
therefore made some comparisons at 55mm on a tripod that really verifies
this. Maybe no surprise, as I did not expect wonders from a kit lens in
this price range, but it's really a bit softer than I expected. In fact
the 55-200VR is sharper at 55mm f/4 than the 18-55 is at 55mm f/8!
However, I know Ken Rockwell writes a lot about how nice his 18-55 is,
while most everybody else say the 18-70 wins hands down. What do you
think, is a Nikkor 18-70 about as sharp as a 55-200VR or would it be no
better than the kit lens I already have?
/per
I have both the 18-70 that came with my D70s, and the 18-55 II that came
with my D40. I like them both just fine, and my photos so far with the 18-55
(mostly indoors in P mode with SB-600) have been very sharp. I haven't
tested it extensively or made elaborate comparisons with the 18-70 or any
other lens, however.

Neil

Compare CA.

I see this a lot - what does CA refer to?

Louise

louise wrote:
RichA wrote:
On May 5, 3:31 pm, "Neil Harrington" wrote:
"per" wrote in message

...

Hi,
I've got a Nikon D40 with the kit 18-55 and the new 55-200VR.
I found my 55-200 to be considerably sharper than the 18-55 GII. I've
therefore made some comparisons at 55mm on a tripod that really
verifies
this. Maybe no surprise, as I did not expect wonders from a kit lens in
this price range, but it's really a bit softer than I expected. In fact
the 55-200VR is sharper at 55mm f/4 than the 18-55 is at 55mm f/8!
However, I know Ken Rockwell writes a lot about how nice his 18-55 is,
while most everybody else say the 18-70 wins hands down. What do you
think, is a Nikkor 18-70 about as sharp as a 55-200VR or would it be no
better than the kit lens I already have?
/per
I have both the 18-70 that came with my D70s, and the 18-55 II that came
with my D40. I like them both just fine, and my photos so far with
the 18-55
(mostly indoors in P mode with SB-600) have been very sharp. I haven't
tested it extensively or made elaborate comparisons with the 18-70 or
any
other lens, however.

Neil

Compare CA.

I see this a lot - what does CA refer to?

Louise
Chromatic Aberration:
http://en.wikipedia.org/wiki/Chromatic_aberration

"louise" wrote
I see this a lot - what does CA refer to?

Louise

CA is Chromatic Aberrations, color shadows at harsh contrast transitions.

Anyway CA is very low at 55 mm for the 18-55 according to Photozone, and
does not seem to be the source of the sharpness problem for me, as the test
pics at 55mm show. Maybe I just have a lemon for a kit lens? What does the
Nikon guarantee cover when it comes to sharpness issues?
/per

per wrote:
"louise" wrote
I see this a lot - what does CA refer to?

Louise

CA is Chromatic Aberrations, color shadows at harsh contrast transitions.

Anyway CA is very low at 55 mm for the 18-55 according to Photozone, and
does not seem to be the source of the sharpness problem for me, as the test
pics at 55mm show. Maybe I just have a lemon for a kit lens? What does the
Nikon guarantee cover when it comes to sharpness issues?
/per



Yes - CA according to photozone is quite low at 55mm, a little higher at
shorter f/l - and not great, but not terrible either.
Have you tested to see if it isn't a backfocus problem with your camera
body? I guess that if the 55-200 is okay, then that's less likely.
Dud "lemon" lenses happen - I guess your problem might be proving it.
First port of call would normally be the retailer that you bought the
camera/lens from. But do some research, perhaps go armed with test
shots where mis-focus and/or camera shake can be eliminated as a
possible cause.

In article ,
=?iso-8859-1?Q?Rita_=C4_Berkowitz?= ritaberk2O04 @aol.com wrote:
Philip Homburg wrote:

Nonsense! The 18-70 is an optical marvel that exceeds the
expectations and specifications of what people demand from a DX
lens. If you must have a DX lens the 18-70 is it.

I guess that people expect very little from a DX lens, because the
18-70 may be decent lens, but it doesn't come close to the 17-35.

Of course it doesn't since my 17-35/2.8 isn't a DX lens, is yours?

I never pay attention to labels on lenses :-)

Why should DX lenses be worse than 'normal' lenses, and why do you think
that people accept worse performance from DX lenses than from full-frame
lenses? There is no full-frame version of the 12-24 DX. So it'd better be
good (or you would have to buy a 1Ds :-)

forget that the 18-70 is a $200 lens while the 17-35/2.8 is a bit more
expensive.

Of course there is the value for money aspect. But if you want good
wide angle performance, you don't get any of the DX Nikkors that start at
18, you get the 17-35.

And even then, I would not be surprised if a 24/2 on full-frame would
be better than then 17-35 on APS-C.


--
That was it. Done. The faulty Monk was turned out into the desert where it
could believe what it liked, including the idea that it had been hard done
by. It was allowed to keep its horse, since horses were so cheap to make.
-- Douglas Adams in Dirk Gently's Holistic Detective Agency

On May 6, 4:13 pm, Rita Ä Berkowitz ritaberk2O04 @aol.com wrote:
RichA wrote:
Nonsense! The 18-70 is an optical marvel that exceeds the
expectations and specifications of what people demand from a DX
lens. If you must have a DX lens the 18-70 is it.

Nikon was sensible, unlike some other companies. They sacrificed some
control over vignetting and distortion in order to better deal with
CA, SA, coma and astigmatism. Even the build quality is good. The
result is arguably the best kit lens currently on the market and they
did it without pushing the price towards high three figures.

Yep, and for being a DX lens and a bit slow it still gives the 17-55mm/2.8
DX a run for a hell of a lot less money.

Rita

IMO the 18-70 is a decent lens and the size and weight are real
pluses. However, it does not compare at all to the 17-55 2.8. The
18-70 is not as sharp at any focal length or any aperture and shows
more vignetting. The build quality is not even close. But of course it
is 1/4 the cost! For me, the extra cost of the 17-55 is worth it.

-Karl

On May 7, 1:58 am, louise wrote:
RichA wrote:
On May 5, 3:31 pm, "Neil Harrington" wrote:
"per" wrote in message

.. .

Hi,
I've got a Nikon D40 with the kit 18-55 and the new 55-200VR.
I found my 55-200 to be considerably sharper than the 18-55 GII. I've
therefore made some comparisons at 55mm on a tripod that really verifies
this. Maybe no surprise, as I did not expect wonders from a kit lens in
this price range, but it's really a bit softer than I expected. In fact
the 55-200VR is sharper at 55mm f/4 than the 18-55 is at 55mm f/8!
However, I know Ken Rockwell writes a lot about how nice his 18-55 is,
while most everybody else say the 18-70 wins hands down. What do you
think, is a Nikkor 18-70 about as sharp as a 55-200VR or would it be no
better than the kit lens I already have?
/per
I have both the 18-70 that came with my D70s, and the 18-55 II that came
with my D40. I like them both just fine, and my photos so far with the 18-55
(mostly indoors in P mode with SB-600) have been very sharp. I haven't
tested it extensively or made elaborate comparisons with the 18-70 or any
other lens, however.

Neil

Compare CA.

I see this a lot - what does CA refer to?

Louise- Hide quoted text -

- Show quoted text -

There are several major aberrations that lens designers have to
contend with. The two worst are (in this order) SA (spherical
aberration) and CA (chromatic aberration).
Spherical aberration is devastating to a lens. This is where light
rays that go through the sides of a lens come to a different focus
point than rays going through the centre. The result is that the
image never achieves good focus, and is suffused in a kind of glow.
Most lenses are well corrected for this but it is the primary cause of
unsharp images at wide apertures. CA, or chromatic aberration is the
failure of all colours of light to come to a common focus. So when
(for e.g.) green is in focus, red and blue are not. This produces the
familiar purple, blue, red colour fringes at light-dark interfaces in
an image. In reality, we only (except in severe cases) see the edge
of an object as showing a coloured fringe, but CA (unfocused red and
blue light) is actually blurred over the entire image, reducing
contrast and effecting colour balance. Other aberrations include
astigmatism (the lens isn't completely an accurate sphere) this show
up on the edge of the field where infinitely small point sources (city
lights at night, etc) assume complex unround shapes. Coma is familiar
to anyone who has used a fast lens wide open. Images at the edge are
blurred and lights (somewhat like with astigmatism) assume seagull or
boomerang shapes. Other things can be poor image contrast caused by
poorly polished lens surfaces, but this is primarily a problem of the
past, lens grinding machines are better now. Lastly, how accurate the
curve is on a lens will determine how well it forms an image, and
poorly figured lenses in long telephotos can cause considerable image
degradation. You don't see this on top quality optics. The use of
aspheric (non spherical lens surfaces)
and high index ED glass is a way to minimize the number of elements
needed and reduce residual aberrations below that of conventional all
spherical lenses using standard glasses.

"Karl Winkler" wrote:

IMO the 18-70 is a decent lens and the size and weight are real
pluses. However, it does not compare at all to the 17-55 2.8. The
18-70 is not as sharp at any focal length or any aperture and shows
more vignetting. The build quality is not even close. But of course it
is 1/4 the cost! For me, the extra cost of the 17-55 is worth it.

-Karl

I'm sure 17-55 is a good lens, but the question was if I would see any
difference using a 18-70 instead of the 18-55.
/per

per wrote:
"Karl Winkler" wrote:

IMO the 18-70 is a decent lens and the size and weight are real
pluses. However, it does not compare at all to the 17-55 2.8. The
18-70 is not as sharp at any focal length or any aperture and shows
more vignetting. The build quality is not even close. But of course it
is 1/4 the cost! For me, the extra cost of the 17-55 is worth it.

-Karl

I'm sure 17-55 is a good lens, but the question was if I would see any
difference using a 18-70 instead of the 18-55.
/per

Did you get an answer in the thread somewhere?
I think that the answer is yes - if you look closely and remember that
sharpness across the frame (not just dead center) is what you want
unless you use strange composition techniques.
But more importantly IMO, it works faster (ring motor AF-s focus), the
front element doesn't rotate (important if using polariser), it has
extra reach to 70mm, and slightly better construction.
It's faults are distortion at the 18mm end (the 18-55 is a bit better
but still bad) and light fall-off with fully wide aperture at 18mm and
70mm. At the 18mm end @f3.5, it is "beyond fixing" as it is at least
1.5 stops, but is much less problem even one stop smaller, and easily
fixed (PTLens $10 software - which will also deal to distortion very
effectively). Apart from light fall-off at the extremes, it is very
usable at maximum aperture - and that's unusual for a consumer zoom lens.
The 17-55 is of course a very good lens. But hell will freeze before I
pay that much for a dx only lens.

Philip Homburg wrote:

I guess that people expect very little from a DX lens, because the
18-70 may be decent lens, but it doesn't come close to the 17-35.

DX isn't the issue; the 17-55/2.8 DX is a much nicer lens than the 18-70
(and for the price it darned well ought to be!). I got the 18-70 and
used it for most of a year, but I was unhappy enough to eventually
upgrade to the 17-55, which is very nice indeed (except that its lens
shade doesn't fit well in any of my camera bags!).