My camera (Rebel XSi) got wet a few weeks ago. It was in the bottom of my backpack, on my back, for 6 hours in wet rain/snow. I brought it into the tent that night and kept it in my sleeping bag to dry it out as a precautionary measure, after removing the battery and card. Fast forward to the next night when I tried to turn it on and got NOTHING. I know I should have had it in a ziploc bag, but what's done is done 😞
So I put it in a bowl of rice for like 4 days. When I removed it and put the battery in it turned on!
It's now been like a week and a half and I tried to take the first photo today. The camera was showing "card full". I erased everything on the card (using the camera), but it still said full. So I took the card out of my point and shoot because I KNOW that one is fine. Rebel still said it was full.
I tried turning it on and off as well as removing the battery, and turning it off then removing the card and turning it on and re-inserting the card. It DID take a couple photos then but I was unable to see either of them (it was showing a screen I'd never seen before), so I turned it off. It showed the "saving" screen (or whatever it says, can't remember off hand) for several minutes until I removed the battery. When I put the battery back in it was saying card full again.
Freaking out here... I've had this camera for like 5 years and it's been through some rough times (very tough little camera!). I'm not in a spot to buy a new one right now, and I'm on a trip where I'd LOVE to get some photos.
Is it the same card that was in it when it got wet? I'd use another card just to rule that out. I'd also reformat the card, in camera. If that doesn't do it, then I would start to suspect the electrical contacts on the card reader, or a short somewhere in the system.
Canon of course doesn't recommend anybody servicing their own cameras, but me personally, I'd pull it apart and look for corrosion or contaminants forming a bridge between contacts. Clean with IPA (not the beer) and Qtips.
I don't think you waited long enough (4 days). Keep it on a warm, not hot, hot pad for much longer. Possibly a month!
By all means get a new card.
If a camera has a short, turning it on is the worse thing to do.
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