Faulty 100-400 IS from B&H

[nico_smit]

I just received my Canon 100-400 IS lens from B&H and I am about to

return the lens as I suspect it to be faulty. Just to confirm my

suspicion I would appreciate jour comments.

 

The problem on my copy of the lens is that the zoom tension ring and

focus ring cannot be adjusted independently. If I hold the zoom

tension ring at the same position the focus ring cannot be turned

over the entire focus range. If I don�t hold the zoom tension ring

it turns with the focus ring, even 360 degrees. This is not how it

is suppose to work, right?

[barmijo]

When the tension ring is tightened I believe it will turn with the focus ring.

[robin_sibson1]

Wrong. When you turn the focus ring, the zoom tenson ring turns with it. When you want to adjust the zoom tension, you hold the focus ring and turn the zoom tension ring relative to it. At least, that is how mine works and it sounds as if yours is the same, in which case there is nothing wrong with it. Weird piece of design, I agree, but that's the way it is.

[michiel_bernhard]

Beste Nico,

 

Ik heb net even mijn 100-400 getest, in principe draait de zoom tension ring altijd mee met de scherpstelring, zo vaak en zo ver rond als je maar wilt. De zoom tension ring kan wel onafhankelijk van de scherpstelring draaien door met de ene hand de scherpstelring vast te houden en met de andere hand de zoom tensionring te draaien. Persoonlijk vindt ik dit niet zo handig ontworpen van Canon. Veel plezier met je lens!

 

Michiel

[wildpicture]

Michiel, please use the english language on this forum. Nico may be able to read the dutch as it is so very similar to his own afrikaans. But other people will wonder what you are talking about.

 

Indeed the design of this tension ring is very strange. On my lens I can only adjust it between "rather tight" and "very tight". There is no real "loose and smooth".

 

Regards,

Hans

[suman]

Nico

That's normal I guess. It works the way you explained. I thgought mine is also faulty but realise that's the it works.

[suman]

Oops, I really messed up my previous post. Sorry.

[john_nastelin1]

Note that B&H is closed from April 5-13, so you might as well hold onto it for a little while to confirm whether it's defective.

[paul_nicol]

Another 100-400 chiming in,, mine is the same way. Normal.

[nico_smit]

Thank you all for setting my mind at ease. Looks like my lens is fine after all.

[markci]

The fact that they're all faulty doesn't mean yours isn't. It's just a bad design (and one reason I sold mine).

[vettesight]

The manual states that this is the correct situation. Personally, ifind it an OK arrangement. My copy seems sharp and easy to use.