Cna a lens 'go soft'?

Weird question, I know.
I've read where folks purchase a new lens and for some reason they 'got' a soft one and had to have it replaced...for defective reasons?

But I have a 70-200 2.8 nonIS that has always been a great lens for me...but seems like recently my shots with it are lacking something...just a tad off in the sharpness department.

The lens has never been dropped.

Can the ...'go bad' after lots of use? Never heard of that before but I'm puzzled.

If your gear hasn't gotten "soft" over time, could it be the photographer?

Have you tried a quick sharpness test on a tripod with manual focusing, preferably live view? I wonder if something is off with your DSLR body's AF.

For me, perceived sharpness decrease usually turned out to be too slow shutter speeds handheld and/or awful lighting.

For sure they can... There are a few adjustable lens elements inside most lenses like centering/tilt which can have a large affect on sharpness. The 24-70 I is known for this... Going soft with more and more use that requires a trip to Canon for a few replacement parts and calibration.

Not sure what goes "bad" inside the 70-200, but my guess is a lens element slowly drifted out somehow (tilt/centering) and Canon needs to calibrate it back again.

Invertalon wrote in post #16291639
For sure they can... There are a few adjustable lens elements inside most lenses like centering/tilt which can have a large affect on sharpness. The 24-70 I is known for this... Going soft with more and more use that requires a trip to Canon for a few replacement parts and calibration.

Not sure what goes "bad" inside the 70-200, but my guess is a lens element slowly drifted out somehow (tilt/centering) and Canon needs to calibrate it back again.

I'll have to chip in. Just sent two lenses in for adjustment, with one being in worse shape from hard knocks during use, so it's definitely possible. Lenses having adjustable attachment points for the internal elements is done for easier calibration by service techs, and also because it lessens the chance the glass will crack from impact; a calibration is inexpensive, a replaced lens element is much more.

marcosv wrote in post #16291635
If your gear hasn't gotten "soft" over time, could it be the photographer?

Have you tried a quick sharpness test on a tripod with manual focusing, preferably live view? I wonder if something is off with your DSLR body's AF.

For me, perceived sharpness decrease usually turned out to be too slow shutter speeds handheld and/or awful lighting.

you forgot to include "bad copy" of the lens lol

Before the advent of AF microadjustment, Fred Miranda said he had his equipment calibrated annually.

gnome chompski wrote in post #16293509
you forgot to include "bad copy" of the lens lol

Actually I didn't forget. Better to focus on eliminating operator error and identifying photographers with unrealistic exceptions before talking about "bad copy" of a lens.

bob_r wrote in post #16293597
Before the advent of AF microadjustment, Fred Miranda said he had his equipment calibrated annually.

do you have a link to this? id really like to read more on this.

wanderx wrote in post #16295184
do you have a link to this? id really like to read more on this.

It was an email that Fred sent me rather than an article.