Loss of sharpness on Canon 100-400

Hello everyone,

I have a question to ask- is it possible for a lens (in my case, the Canon 100-400) to lose sharpness? I have been using this lens since 2008 (it is the "dust pump" model not the newer one) and I have traveled all over the world with it (Australia, Belize, Brazil, Costa Rica, Indonesia, Singapore, South Africa, Sri Lanka, etc. some multiple times). Despite a few superficial blemishes from years of wear, there does not appear to be anything mechanically wrong with it. However, over the last couple of years, I've noticed it just doesnt "nail" some of the shots that it would have before. It seems I need to be almost entirely still to get a sharp wildlife shot, whereas before I could be moving or on a boat, etc. and still get the shot. Should I give up and get a new lens or do you think a cleaning may help? Can accumulation of dust inside the lens cause this? I don't think it is the camera itself. I have a Canon 7D Mark II and I purchased it much more recently (November 2016) and my smaller lens doesn't have the same problem.

Thanks!

In addition to the above comment about wear and tear, is it possible that after 12 years your hand might not be as steady as it was back then

Seriously though, have you checked that the IS is actually working as it should (or at all) ?

I owned one from 2009 to 2017 and it was a great lens. The only signs of wear and tear on mine was the zoom creep got worse, and the tension ring had to be tightened all the up to stop it.

Worth noting that the IS on the 100-400L ii is significantly better - 4 stops vs 2 stops.

Colin

Cporosus1 wrote:

Hi everyone, sorry for the delay. Here are some photos of my settings. Also attached a recent snake closeup...it looks fine but its not tack sharp. Settings were- f/14, 1/640 sec., iso400, 100-400mm lens Does everything look right for wildlife?

I am not familiar with a 7D ii so I cannot comment of specific settings.

Was the snake moving a little or perfectly still (I would guess moving a little) ?

How far away was the snake from the camera (ie. the subject distance) ?

Were you in Servo AF ?

Were you using BBF (Back Button Focusing) ?

I seldom use spot AF point because I find that usually just the normal single AF point gives a better result.

At f14 you are not going to get the sharpest result from the lens as diffraction is becoming evident.

The white scales under the rear end of the head appear to be quite sharp, which makes me think that perhaps the snake moved a little between you locking AF (presumably on the eye ?) and the shot being taken ?

Colin

Cporosus1 wrote:

Hello everyone,

I have a question to ask- is it possible for a lens (in my case, the Canon 100-400) to lose sharpness? I have been using this lens since 2008 (it is the "dust pump" model not the newer one) and I have traveled all over the world with it (Australia, Belize, Brazil, Costa Rica, Indonesia, Singapore, South Africa, Sri Lanka, etc. some multiple times).

You can have been unlucky and it got a bump somewhere along the way misaligning the lens elements. Try sending it in for adjustment.