topic Re: My T3i has suddenly become slow in writing to the memory card. in EOS DSLR & Mirrorless Cameras

My T3i has suddenly become slow in writing to the memory card.

ScottHolder — Tue, 19 Aug 2014 17:05:04 GMT

I used to be able to take shots almost as fast as I could press the shutter, but now I get no more than 5 shots before I get the BUSY message and have to wait. Same with continuous shooting mode. I have a fully charged battery, and the memory cards are formatted in the camera. It happens with both a Lexar SDHC 4GB card and a SanDisk Ultra 16GB card. This problem just started today; I've had the camera since January.

Re: My T3i has suddenly become slow in writing to the memory card.

hsbn — Tue, 19 Aug 2014 18:07:05 GMT

are you using the same card? Are you switching to RAW instead of JPG?

Re: My T3i has suddenly become slow in writing to the memory card.

ScottHolder — Tue, 19 Aug 2014 18:23:39 GMT

I always shoot in RAW. I first had the problem with the Lexar card. I then tried the SanDisk, and it has the same problem.

Re: My T3i has suddenly become slow in writing to the memory card.

ZCDavis — Tue, 19 Aug 2014 21:28:14 GMT

Are you certain that you're not just shooting faster and, thus, maybe just now noticing it for the first time?

Without pulling out my t3i to double check, 5 to 7 RAW images shot at the camera's ~3 FPS max burst rate sounds about right from what I've experienced with mine using UHS-1 90 meg/s write speed cards.

What write speed cards are you using? I vaguely recall reading somewhere that the t3i writes at around 40 megs/s, so if you're using cards with speeds slower than that, it'll negatively impact your max burst size before you hit that dreaded write buffer.

Re: My T3i has suddenly become slow in writing to the memory card.

ScottHolder — Wed, 20 Aug 2014 03:09:03 GMT

I'm not sure of the write speeds, but the Lexar is Class 4 and the SanDisk is Class 10. I first noticed the problem when I was trying to take multiple shots of a heron in flight, but I've done things like that before with no trouble.

The main thing is that the time to write to the disk and clear the buffer seems much longer than normal. I tested it just now by filling up the buffer and timing how long it takes for the LED and the available shots number to stop blinking. It takes about 17 seconds.

Re: My T3i has suddenly become slow in writing to the memory card.

ebiggs1 — Wed, 20 Aug 2014 15:13:29 GMT

"It takes about 17 seconds."

That seems about right to me. I would get a new SD card anyway. You might cut off a couple seconds.

The image file size, number of possible shots, and maximum burst will vary depending on the shooting conditions (3:2 aspect ratio, subject, memory card brand, ISO speed, Picture Style, Custom Functions, etc.).

You didn't happen set it to jpg + RAW?

Re: My T3i has suddenly become slow in writing to the memory card.

ScottHolder — Thu, 21 Aug 2014 03:04:06 GMT

No, I didn't have it set to .jpg + RAW, it's always RAW only.

I checked reviews online, and the only buffer clearing time I found said 11 seconds, significantly shorter than 17.

I also tried recording movies just now. With both the class 4 4GB and the class 10 16GB, the recording stopped automatically at 3 seconds...

Re: My T3i has suddenly become slow in writing to the memory card.

ebiggs1 — Sun, 31 Aug 2014 13:29:48 GMT

If you still think it too slow, send it to Canon Service for evaluation.

But I would buy a brand new high quality SD card first. A fast SD card.

Re: My T3i has suddenly become slow in writing to the memory card.

ScottHolder — Sun, 31 Aug 2014 03:13:08 GMT

I called Canon, and they suggested to first try a new card with a faster write speed. They pointed out that the write speed isn't indicated on the card (that's only the read speed), but on the packaging. They said that if that didn't help, to send in the camera for service. I got a card with a 50mb/s write speed today. Much faster buffer clearing speed, and videos are recording fine 🙂

Canon's service dept. is very good. Quick response, pleasant, knowledgeable people in the USA 🙂

Re: My T3i has suddenly become slow in writing to the memory card.

renman — Mon, 31 Jul 2017 17:51:12 GMT

The solution reported didn't help me but I figured out what the problem was for me and maybe for others.

I was taking star trails with a 30 secs exposure and had noise reduction turned on. The manual indicates it can take as long as the exposure to for the noise reduction process to complete effectively doubling the time between shots.

From the EOS T3i manual.

Re: My T3i has suddenly become slow in writing to the memory card.

RebelDog — Thu, 01 May 2025 05:24:01 GMT

That's exactly right. And it's a pain in the butt! I take 10 minute astroexposures and I have to wait another 10 minutes for it to return to the ready state. (You have to use an external control and set the exposure to "bulb"). I can't see in manual mode where to turn off the noise reduction though (haven't looked but sure don't remember it- so, pending my looking for it specifically). But, at the end of the day, it's all software and unvalidated marketing crap. That's my T3i. I have a T3. It doesn't do that. And the images- even at 10 minutes- are equally good. Bottom line, they've wasted untold hours of peoples' time with a very questionable feesure. The tilt screen on the T3i is really necessary for astrophotography unless you're a contortionist. But I'm going on a two day astrophotography trip and I'm taking my T3 for objects that are at a low angle just so that I don't have to wait for the noise reduction on an object where I really don't need the tilt screen.