Here is another test worth trying. Switch off the Camera then dismount the lens for 30 seconds then reattach the lens and leave the camera switch off over night to see if there is any power drain.

I'm suggesting this to see if physically removing the lens after powering off the camera will break the electronic circiut that is causing the drain and if it remains so even once the lens has been reattached and the camera being left off for a long period.

The other thing is that maybe this problem is only on your copy of this lens.

Both of the above suggestions are good. Will give it a try on my "T4i". (will watch my 4s and Ts!)

Keep in mind I've used this Tamron lens on other rebel bodies with no negative effect. The only problem with trying all these thing is it leaves me no time to actually use the camera! Please don't take this the wrong way but, these various tests benefit Canon or Tamron, not so sure there's a plus for me.

flowrider wrote in post #14860554
I thought that Tamron was on of the third parties that actually licensed the AF technology that's why you don't ever hear of a Tamron lens needing to be rechipped to work with a newer camera unlike older Sigmas.

One thing I've learned by talking with various Canon personnel about this issue is that Canon DOES NOT license it's lens technology to ANY third party lens manufacturers. It is always reverse engineered (at least that is what I've been told more than once).

Bakewell wrote in post #14861648
One thing I've learned by talking with various Canon personnel about this issue is that Canon DOES NOT license it's lens technology to ANY third party lens manufacturers. It is always reverse engineered (at least that is what I've been told more than once).

It's just that some third party lens makers are better at reverse engineering than others.

The testing might not slow you down. Go into the menu and check the battery meter that reads in percentage as an indicator. Do this when beginning a test and perhaps 8 hours later. I have gone for several weeks on an unused 60D and only lost about 3% to 5%. If you are killing the battery in two days, your charge should be dropping off very rapidly; I would think 10% more or less in 8 hours.

This brings up another thought, are you absolutely certain the battery is in great shape?

John from PA wrote in post #14862158
The testing might not slow you down. Go into the menu and check the battery meter that reads in percentage as an indicator. Do this when beginning a test and perhaps 8 hours later. I have gone for several weeks on an unused 60D and only lost about 3% to 5%. If you are killing the battery in two days, your charge should be dropping off very rapidly; I would think 10% more or less in 8 hours.

This brings up another thought, are you absolutely certain the battery is in great shape?

Two things...I've noticed the battery indicator on the T4i is not real sensitive...once it starts to move it goes fast and second I've used three different Canon batteries with the same end result...this includes two new batteries from Canon service

Same thing happens with my G1X. Once it stops showing a complete battery icon, running out of power is imminent.
Eduardo

Bakewell wrote in post #14863507
Two things...I've noticed the battery indicator on the 4Ti is not real sensitive...once it starts to move it goes fast and second I've used three different Canon batteries with the same end result...this includes two new batteries from Canon service

match14 wrote in post #14860939
Here is another test worth trying. Switch off the Camera then dismount the lens for 30 seconds then reattach the lens and leave the camera switch off over night to see if there is any power drain.

I'm suggesting this to see if physically removing the lens after powering off the camera will break the electronic circiut that is causing the drain and if it remains so even once the lens has been reattached and the camera being left off for a long period.

Sorry...tried this and the battery is still dead within 48 hours....

Just an update regarding this issue.

Sent the Tamron to service and they replaced it (extremely early serial #) with a current production run unit. Problem appears to be solved and I'am currently receiving "normal" battery life.

With the grip issue on your T4i, did you send it to Canon or swap it locally? Just asking because Canon may have repaired it instead of shipping you a new one, unless of course the serial number changed.

Good that you got resolution, sounds like something was crazy with that other lens.

Canon doesn't license their tech to anyone as far as I know, too much business in the lenses to give cheaper competition an edge.

And no, off is never off, there is always power being used and active, it keeps the clock running, and yes if you remove/put in a new memory card usually the red light will blink briefly, so there are still some parts of the camera with electricity at all times.

Regarding the grip issue...Canon sent a new camera to resolve. This did not solve the battery issue. It still wound down within 48 hours. Not sure if this answers your question...

I think I have the same problem with my Sigma 24-70 f2.8. I got the T4i about 4 weeks ago with the 18-135 STM and that has been on it until last weekend. On Sunday I put on the Sigma 24-70 and took a few shots all was well (can't confirm batter power at this time) - never really had a better run down with the T2i this replaced. On Thursday I pick up the camera and turn it on it comes on and the screen goes black almost immediately. I panic thinking the camera has gone faulty having never had battery issues before but then I try my spare battery and all is fine that is at about 3/4 charge. I then charge up both batteries fully and place the new one back in the camera. Took a few shots turned it off and put it away with the Sigma 24-70 on. Friday afternoon I turn on the camera - same thing that happened as Thursday; it comes on then goes off almost immediately the battery is fully discharged. I place my spare fully charged battery in and took 5 shots then made sure to turn off (doubting that I had the other times). I just checked 8 hours later and the battery is at about 50%. It has lost half its power just sitting there off in 8 hours. I came looking online for similar issues and found this post. If anyone has a solution I would be happy to try it. I am going to try some of the suggested methods above turn off OS etc. and see if it helps.

Hi Dave, glad you got your issue sorted, happy shooting. Chris, I am having issues with my 7d at the moment, I limped it through a couple of weeks to get my holiday out of the way and now I hope to get it sorted. I have my batteries going flat to the point of dead whilst the battery is in the camera within a few days.
Charge the batteries 100% and leave them out of the camera for a few days then check the charge. If thats ok, then put battery into camera, but, take the lens off the camera body to try to eliminate that from the equation. That should pinpoint body, lens or battery as your problem.
Good luck
Ian

hi dave,

i'm a user of the canon t4i and i've just bought the tamron 24-70 from B&H NY.
i've just received it yesterday (cause i'm not resident in NY) and i had the same problem as you for the battery, ( woke up this morning and the battery was at 0).
how can i resolve the problem ( i think the serial number of this tamron is 014XXX) so i think it's not an earlier serial # ( but i'm not sur).

how about you, is everything ok now? and what should i do now ( return the objectif to B&H or contact tamron??), need your advice.

thx

Mehdiben wrote in post #15235809
hi dave,

i'm a user of the canon t4i and i've just bought the tamron 24-70 from B&H NY.
i've just received it yesterday (cause i'm not resident in NY) and i had the same problem as you for the battery, ( woke up this morning and the battery was at 0).
how can i resolve the problem ( i think the serial number of this tamron is 014XXX) so i think it's not an earlier serial # ( but i'm not sur).

how about you, is everything ok now? and what should i do now ( return the objectif to B&H or contact tamron??), need your advice.

thx

Sorry to hear you're having problems. My issue seems to have been resolved. It was resolved by returning the lens to Tamron stating the issue I was having. You can get a warranty service form from their website. They replaced the lens. The turnaround was about 10 days. Good luck!