Canon T3i Performance

Average to slower than average speed for consumer digital SLR these days.

The Canon Rebel T3i turned in a sluggish startup time, though shutdown was super fast and difficult to measure. (Automatic sensor cleaning was enabled, by default.) The Canon Rebel T3i's buffer clearing times were a little long, especially considering the shallow buffers.

The Canon Rebel T3i's Play to Record mode switching time was quite sluggish for an SLR, though Record to Play and displaying a recorded image are about average.

The Canon Rebel T3i's full autofocus shutter response was a touch slow using our standard single-point AF test, at 0.283 second. Interestingly, switching to Auto Selection AF and allowing the camera to choose the focus point reduced shutter lag to 0.160 second, which is very good. As expected, enabling the built-in flash increased full AF lag a bit, to 0.260 second. (The camera emits flash metering pulses and analyses the results before taking the final flash exposure.) "Prefocusing" the camera by half-pressing and holding down the shutter button before the final exposure resulted in a lag time of only 0.087 second which is good for a consumer SLR. Shutter lag in Manual focus was a bit slower than prefocused, at 0.114 second, which is still quite fast. In Continuous focus mode, shutter lag was 0.129 second, very good.

The Canon Rebel T3i's AF lag time in Live View mode was longer than using the optical viewfinder (as expected). We measured 1.176 seconds using "Quick Mode" (phase-detect AF) which is a bit slow for PD AF. Surprisingly, Live Mode (contrast-detect) AF was faster at 0.826 second, but keep in mind we don't defocus the lens between trials, so phase-detect AF will likely be faster in most real-world situations. Prefocused, the Canon Rebel T3i's shutter lag was pretty fast in Live View mode, at 0.084 second.

To minimize the effect of different lens' focusing speed, we test AF-active shutter lag with the lens already set to the correct focal distance. We also use the same Sigma 70mm f/2.8 macro with every camera (on all platforms except Four Thirds/Micro Four Thirds and Nikon consumer models lacking an in-body focus motor), to further reduce variation, and because our tests showed that focus-determination time with this lens was close to the fastest, across multiple camera bodies from different manufacturers. Being an older design with a non-ultrasonic motor, it wouldn't be the fastest at slewing from one focus setting to another, but that's exactly the reason we measure focus determination speed, which is primarily a function of the camera body, vs focus adjustment speed, which is primarily a function of the lens.

Shot-to-shot cycle times in the Canon T3i's single-shot mode were about average for an SLR, at 0.44 second for large/fine JPEGs, 0.46 second for RAW and 0.39 second for RAW + large/fine JPEGs.

Continuous mode speeds are also about average for a consumer model, at about 3.6 frames-per-second for large/fine JPEGs or RAWs, and 3.3 frames-per-second for RAW + large/fine JPEGs. Measured buffer depths in continuous mode were low at 9 frames for large/fine JPEGs, 5 frames for RAW mode and only 3 frames for RAW+ L/F JPEG. (Note that in our cycle time testing we shoot a target consisting of a fine-grained digital noise pattern, designed to be very hard to compress. This gives us worst-case buffer capacity numbers: You're likely to see greater buffer capacity when shooting more normal subjects.)

The Canon Rebel T3i's flash took an average of 3.2 seconds to recharge after a full-power discharge, which is pretty fast.

Connected to a computer or printer with USB 2.0, the Canon Rebel T3i's download speeds are quite fast.

Bottom line, the Canon Rebel T3i is average to slower than average in most aspects of its operation for a consumer SLR. While continuous mode speeds aren't state-of-the-art, they are fast enough for most moving subjects, and shutter lag and cycle times are fair. Buffer sizes are small, and clearing times are sluggish with our 30MB/s SDHC card.

Battery
Below average battery life for a lithium-ion SLR design.

The Canon T3i uses a custom rechargeable lithium-ion battery for power, and ships with a charger. Battery life is bellow average when using the optical viewfinder even for a consumer SLR, and of course Live View mode draws more power reducing battery life. We recommend you pick up a spare battery and keep it freshly charged and on-hand for extended outings. The Canon T3i is compatible with an optional BG-E8 battery grip, which can double capacity with two rechargeable lithium-ion battery packs. The grip also accepts AA batteries.

The table above shows the number of shots the Canon Rebel T3i is capable of (on a fully-charged rechargeable battery), based on CIPA battery-life and/or manufacturer standard test conditions.

(Interested readers can find an English translation of the CIPA DC-002 standards document here. (180K PDF document))

Storage
The Canon Rebel T3i accepts SD/SDHC/SDXC memory cards, and does not ship with a card. Canon recommends a Class 6 card or faster for recording HD movies. UHS-I compliant cards are supported, but the camera does not take advantage of their increased bus speeds.

We strongly recommend buying a fast, large capacity SDHC/SDXC memory card for the Canon Rebel T3i: at least a 4GB card, preferably a 8 or 16GB one, to give yourself extra space for extended outings, or when shooting RAW files or video. Check the shopping link above, cards are really cheap these days, so no reason to skimp.)