17-40 Doesn't work in the cold...SOLUTION

So my 17-40 has something wrong with it (probably just needs cleaning) were when it gets cold it stops focusing properly. This last weekend I was shooting relay for life so I obviously needed it to work, so I came up with the idea of rapping a bandana around it with a hand warmer stuff between to keep it warm. And low and behold it worked .

In my first round of testing it didn't work since I was putting the lens in a seal container and the handwarmer needs oxygen to work, but after just putting it outside it worked perfectly .

Just wanted to show a creative way of solving a gear problem.

Here are some shots from the freezer test.

Too much lube,which increases viscosity in the lowered temp setting.

I often shoot mine in temps lower than forty below ambient,with no means of insulation or increase in temp.

I've been using hand warmers in ziplock bags for a while to keep the lenses warmer. I do it mostly for condensation though. They work very nicely.

Works better for batteries.

I have the same lens. I guess I should finally read the manual regarding operating temps.

How cold did it get for the lens to start not working properly?

I'd not field a lens that dragged it's feet and would send it off to be cleaned(degreased).

I also use this lens at -35 with no issues, man your lens must have a quart of oil in it to fail like that, Instead of wrapping it with a bandana, I would wrap it in bubble wrap, and send it to Canon.

Relentless Pursuit wrote in post #10258289
I'd not field a lens that dragged it's feet and would send it off to be cleaned(degreased).

Yes I know the problem is regarding the lube. And I will send it in, but don't really have the $ to right now (read avg. college student). Canon via email is also pulling the "send it and we can quote you" bs.

And for cold...I'd say the lens (ie the whole thing) only has to get to low 50's for it to start acting up. So like if I went from room temp to shooting in low 50's weather it takes maybe an hour. Really shouldn't be something to worry about in most of them.

I wasn't guessing.

Relentless Pursuit wrote in post #10259724
I wasn't guessing.

no one thought you were...not sure why this statement was needed...

To shift your focus.

Pun intended.