I rented a Canon 17-40L from Vistek Toronto recently and the
lens was a big yawn. It was not what I expected and I was seriously
disappointed. There was no visual increase in performance from my
'lowly' 18-55 EFS and there was so much dandruff-crud inside the
lens it was scary. Granted, its a rental lens but holy cow I thot
L glass was weather sealed???????? How could so much garbage enter
a lens when its supposed to be sealed from the elements???

I expected the 17-40L images to POP over my old EFS lens images.
They did not.

After using it and comparing it to my "cheapo lens", I was shocked!
There was no great increase in image quality image to image. I
prefered my kit lens! I shoot only Raw in AV or Manual. CS2raw.
Sans Jpeg.

Whats going on? Are your 17-40L lenses full of internal dust?
Other L glass full of dust?
Whats with Canon "L" weather-sealing on lenses over the long term usage?

I'm looking at the other alternatives seriously like Sigma and Tamron.
My Bigma keeps on getting it done well. As my old APO 70-300 Macro.
Very little internal dust in those lenses I own.

Is Canon L glass really worth it or are other manufacturers of alternative
3rd party glass getting it?

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