Re: Manual focus of non-full-time manual focus lenses?

On Mon, 9 Jun 2008 21:35:26 +0800, Wilba wrote:

Just putting the lens cap on is not a problem.

But a bump on the front of the lens while it's auto-focussed would be. I
find it hard to believe that lenses would be built with such a serious
weakness.

These inexpensive lenses are probably able to withstand a
reasonable amount of turning force as well as moderate bumps. If
they would be damaged by the slightest of bumps, a huge number of
these lenses would be damaged after all these years on the market,
and if they had been, I find it hard to believe that such a design
flaw wouldn't have been widely known by now.

When DPReview clumsily said :

"The manual focusing ring rotates on autofocus, and care
must be taken not to move it accidentally with the lens set
to AF, to avoid damaging the motor."

I'm sure that they didn't mean that if you accidentally touch, or
accidentally try to rotate the ring the lens will immediately be
damaged. I'm assuming that if that attempt is made to rotate the
ring, you'll notice that there will be resistance, and that damage
won't occur unless you don't take the hint and try to use much more
than the normal amount of force. If you do that, you'll probably
end up damaging the lens's internal gears.

.

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