How big a lens to flex a plastic body?

Someone came into a camera store the other day and traded in his D80
for a D200. He said he did it because the large zoom (heavy) he was
using was flexing the body outward slightly at the mount. I think it
was the 80-400mm. The sales person asked if he was supporting the
lens with his hand. He said he was but still felt that the body was
being flexed slightly when he moved fast to shoot sports subjects. The
D80 body appears to be about as robust as a plastic body is right
now. Which make me wonder about the dynamics of longer heavy zooms
used on lesser bodies than the D80. Obviously, given the speed and
focal length of these lenses, it wouldn't take much misalignment to
effect focus on the sensor.

RichA wrote:
Someone came into a camera store the other day and traded in his D80
for a D200. He said he did it because the large zoom (heavy) he was
using was flexing the body outward slightly at the mount.


Hmmm, but the D80 has a metal chassis as well as a metal lens mount. I would
assume (although I didn't check), that the lens mount connects directly to
the chassis.

jue

On Sun, 01 Jul 2007 09:50:50 -0700, RichA wrote:
: Someone came into a camera store the other day and traded in his D80
: for a D200. He said he did it because the large zoom (heavy) he was
: using was flexing the body outward slightly at the mount. I think it
: was the 80-400mm. The sales person asked if he was supporting the
: lens with his hand. He said he was but still felt that the body was
: being flexed slightly when he moved fast to shoot sports subjects. The
: D80 body appears to be about as robust as a plastic body is right
: now. Which make me wonder about the dynamics of longer heavy zooms
: used on lesser bodies than the D80. Obviously, given the speed and
: focal length of these lenses, it wouldn't take much misalignment to
: effect focus on the sensor.

I'm neither a metallurgist nor an organic chemist, but my impression is that
modern polycarbonate plastics are at least as stiff as most metals. If you use
a huge, heavy lens with any camera body and don't support it correctly, you
have to expect whatever happens.

Bob

"RichA" wrote in message
ups.com...
Someone came into a camera store the other day and traded in his D80
for a D200. He said he did it because the large zoom (heavy) he was
using was flexing the body outward slightly at the mount. I

Never, ever, fly in a Boeing 787 if you are afraid of plastic. It has a
plastic body.

Owl

RichA wrote:
Someone came into a camera store the other day and traded in his D80
for a D200. He said he did it because the large zoom (heavy) he was
using was flexing the body outward slightly at the mount. I think it
was the 80-400mm. The sales person asked if he was supporting the
lens with his hand. He said he was but still felt that the body was
being flexed slightly when he moved fast to shoot sports subjects. The
D80 body appears to be about as robust as a plastic body is right
now. Which make me wonder about the dynamics of longer heavy zooms
used on lesser bodies than the D80. Obviously, given the speed and
focal length of these lenses, it wouldn't take much misalignment to
effect focus on the sensor.

If it makes him feel good and he has the money, Why not. In real life
I can't see it being a problem. However I tend to look at results and if I
am happy with them, I don't see problems. Some people spend more time
looking for problems than practicing their art. Maybe they don't know
photography is more art than science?

--
Joseph Meehan

Dia 's Muire duit

"RichA" wrote in message
ups.com...
Someone came into a camera store the other day and traded in his D80
for a D200. He said he did it because the large zoom (heavy) he was
using was flexing the body outward slightly at the mount. I think it
was the 80-400mm.

Was it your son DickA? I., mean, come on.

Greg
--
Ticket******* tax tracker:
http://ticketmastersucks.org/tracker.html

Dethink to survive - Mclusky

On Sun, 01 Jul 2007 14:21:07 -0700, G.T. wrote:


"RichA" wrote in message
ups.com...
Someone came into a camera store the other day and traded in his D80
for a D200. He said he did it because the large zoom (heavy) he was
using was flexing the body outward slightly at the mount. I think it
was the 80-400mm.

Was it your son DickA? I., mean, come on.

Greg


Bro, the thought of a fertile Dick[A] is too horrifying to contemplate.
--
Slack

"RichA" wrote in message
ups.com...
Someone came into a camera store the other day and traded in his D80
for a D200. He said he did it because the large zoom (heavy) he was
using was flexing the body outward slightly at the mount. I think it
was the 80-400mm. The sales person asked if he was supporting the
lens with his hand. He said he was but still felt that the body was
being flexed slightly when he moved fast to shoot sports subjects. The
D80 body appears to be about as robust as a plastic body is right
now. Which make me wonder about the dynamics of longer heavy zooms
used on lesser bodies than the D80. Obviously, given the speed and
focal length of these lenses, it wouldn't take much misalignment to
effect focus on the sensor.

Oh, no! Oh me, oh my... Whatever shall I do?

I just ordered the 100-400mm lens for a test drive on my shoddy, inferior,
plastic Rebel XT. No doubt, the camera will be destroyed over the next two
weeks.

Damn. Wish I'd known about this before.

dwight

"dwight" wrote in message
. ..
"RichA" wrote in message
ups.com...
Someone came into a camera store the other day and traded in his D80
for a D200. He said he did it because the large zoom (heavy) he was
using was flexing the body outward slightly at the mount. I think it
was the 80-400mm. The sales person asked if he was supporting the
lens with his hand. He said he was but still felt that the body was
being flexed slightly when he moved fast to shoot sports subjects. The
D80 body appears to be about as robust as a plastic body is right
now. Which make me wonder about the dynamics of longer heavy zooms
used on lesser bodies than the D80. Obviously, given the speed and
focal length of these lenses, it wouldn't take much misalignment to
effect focus on the sensor.

Oh, no! Oh me, oh my... Whatever shall I do?

I just ordered the 100-400mm lens for a test drive on my shoddy, inferior,
plastic Rebel XT. No doubt, the camera will be destroyed over the next two
weeks.

Damn. Wish I'd known about this before.

Be carefull, that Rebel XT may blow up in your face as soon as you attach
that lens. The Rebel XT is certified for only 6 oz and under plastic
lenses.

Greg
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Ticket******* tax tracker:
http://ticketmastersucks.org/tracker.html

Dethink to survive - Mclusky

RichA obsesses a lot here. Just plonk him.