The Canon 6D offers a 20.2 megapixel full-frame sensor in a compact DSLR body size. Its DIGIC 5+ Image Processor enables up 4.5 frames per second continuous shooting. It supports Ultra High Speed (UHS-I) Secure Digital memory cards for fast write speed.
The following tests compare the performance of 32 high-speed SD cards in the Canon 6D and reveal the fastest card for this camera. Many SD cards claim a high transfer rate, but they are often only quoted with a read speed; the write speed may be significantly lower. Furthermore, write speed may be limited by the device or camera in which it is used, as is the case with the Canon 6D. Paying a premium price for a fast card may provide diminishing returns in this camera.
The most direct speed comparison uses write speed, a measurement of the rate the camera writes pictures to the card. This speed is most important during sustained burst shooting. Write speed results are dipslayed below in the write speed test. How the write speed impacts actual performance is shown in the continuous shooting test, a measurement of how many shots can be taken in 30 seconds using three different image settings. A detailed performance analysis explains some details found during testing and recommended SD cards for the 6D are provided based on the test results.
The camera is placed on a tripod and aimed at a detailed test scene with controlled lighting. Manual focus is set using Live View at 10X magnification. A timed remote shutter release provides consistent time intervals and minimizes camera movement throughout the tests. The write time is determined by reviewing a video of the card access light and is accurate to within a few hundredths of a second. The total number bytes written to the card divided by the write time equals the write speed in megabytes per second (1 MB = 1,048,576 bytes). Write speed is provided for RAW image format (RAW+JPEG and JPEG have lower write speeds).
|Average Write Speed (MB/s)||Price|
|SanDisk Extreme Pro 95MB/s 64GB||64||36.1||$34.95|
|SanDisk Extreme Pro 95MB/s 32GB||32||36.0||$21.95|
|SanDisk Extreme Plus 80MB/s microSD 32GB||32||35.5||$24.95|
|SanDisk Extreme 60MB/s 64GB||64||35.4||$53.99|
|SanDisk Extreme 60MB/s 32GB||32||35.3||$29.99|
|SanDisk Extreme 45MB/s 32GB||32||35.1||$16.95|
|Kingston U3 90/80 MB/s 64GB||64||35.0||$32.40|
|SanDisk Extreme Plus 80MB/s 64GB||64||34.7||$64.95|
|SanDisk Extreme Plus 80MB/s 32GB||32||34.6||$34.95|
|Kingston U3 90/80 MB/s 32GB||32||34.5||$17.99|
|Kingston Class 10 UHS-I 64GB||64||34.5||$28.95|
|Transcend 95/85 MB/s U3 32GB||32||34.0||$22.99|
|Toshiba Exceria Pro UHS-II 32GB||32||33.8||$113.18|
|Patriot EP Pro 90MB/s 32GB||32||33.4||$24.64|
|Transcend 95/60 MB/s U3 64GB||64||33.4||$27.84|
|Lexar Professional 600x 64GB||64||33.2||$47.93|
|SanDisk Extreme Pro 280MB/s UHS-II 32GB||32||33.1||$57.08|
|Kingston Ultimate 32GB||32||33.1||$14.32|
|PNY Elite Performance 64GB||64||33.1||$34.95|
|Sony 94MB/s 32GB||32||32.8||$26.29|
|Sony 95MB/s U3 64GB||64||31.7||$41.95|
|Sony 95MB/s U3 32GB||32||31.6||$24.99|
|Toshiba Exceria Type 1 32GB||32||30.7||$137.68|
|Lexar Professional 600x 32GB||32||30.7||$55.37|
|Lexar Professional 400x 32GB||32||28.9||$13.95|
|Transcend 600x 32GB||32||26.8||$12.99|
|Panasonic MicroP2 UHS-II 32GB||32||26.8||$189.99|
|PNY Elite Performance 90MB/s 32GB||32||26.3||$19.95|
|Samsung PRO 64GB||64||24.3||$52.73|
|Samsung PRO 32GB||32||20.2||$29.99|
|Toshiba Exceria Type 2 32GB||32||19.8||$68.07|
|Samsung EVO 32GB||32||16.7||$9.99|
The Canon 6D burst shooting test measures the number of images taken in 30 seconds using three different image settings: RAW+JPEG, RAW, and JPEG. The JPEG setting is Large, Fine. It must be emphasized that the image subject affects the number of images that can be taken. Detailed subjects create large file sizes, which take longer to write and decrease the number of images that can be taken in a given time interval compared with simple subjects. This test creates average file sizes of 28.5MB RAW and 10.4MB JPEG. The test is optimized to show the difference in write speed between cards, rather than an optimistic value provided by a more simple image subject.
|Continuous Shooting – Images in 30 Seconds||Lowest|
|SanDisk Extreme Pro 95MB/s 64GB||64||33||49||110||$34.95|
|SanDisk Extreme Pro 95MB/s 32GB||32||33||49||110||$21.95|
|SanDisk Extreme Plus 80MB/s microSD 32GB||32||33||48||108||$24.95|
|SanDisk Extreme 60MB/s 32GB||32||32||48||109||$29.99|
|SanDisk Extreme 45MB/s 32GB||32||32||48||108||$16.95|
|Kingston U3 90/80 MB/s 64GB||64||32||48||108||$32.40|
|Kingston U3 90/80 MB/s 32GB||32||32||48||108||$17.99|
|SanDisk Extreme 60MB/s 64GB||64||32||48||108||$53.99|
|Transcend 95/85 MB/s U3 32GB||32||32||47||105||$22.99|
|Samsung PRO 64GB||64||32||38||60||$52.73|
|SanDisk Extreme Plus 80MB/s 32GB||32||31||48||108||$34.95|
|Kingston Class 10 UHS-I 64GB||64||31||48||107||$28.95|
|SanDisk Extreme Plus 80MB/s 64GB||64||31||48||107||$64.95|
|Kingston Ultimate 32GB||32||31||47||107||$14.32|
|Patriot EP Pro 90MB/s 32GB||32||31||47||106||$24.64|
|Toshiba Exceria Pro UHS-II 32GB||32||30||47||107||$113.18|
|Sony 94MB/s 32GB||32||30||46||104||$26.29|
|SanDisk Extreme Pro 280MB/s UHS-II 32GB||32||30||46||104||$57.08|
|Sony 95MB/s U3 64GB||64||29||45||101||$41.95|
|Sony 95MB/s U3 32GB||32||29||45||101||$24.99|
|Toshiba Exceria Type 1 32GB||32||29||44||99||$137.68|
|Transcend 95/60 MB/s U3 64GB||64||28||46||104||$27.84|
|PNY Elite Performance 64GB||64||28||46||103||$34.95|
|Lexar Professional 600x 32GB||32||28||44||99||$55.37|
|Lexar Professional 400x 32GB||32||28||42||95||$13.95|
|Samsung PRO 32GB||32||28||33||62||$29.99|
|Samsung EVO 32GB||32||28||29||64||$9.99|
|Lexar Professional 600x 64GB||64||27||46||104||$47.93|
|Transcend 600x 32GB||32||26||40||91||$12.99|
|PNY Elite Performance 90MB/s 32GB||32||26||39||89||$19.95|
|Panasonic MicroP2 UHS-II 32GB||32||25||40||89||$189.99|
|Toshiba Exceria Type 2 32GB||32||21||33||71||$68.07|
Although the Canon 6D supports UHS-I SD cards, its write speed is well below the theoretical maximum provided by UHS-I (104MB/s). In continuous shooting the 6D write speed topped out around 36MB/s. One interesting observation is the fastest 11 SD cards in this test were all SanDisk and Kingston. Samsung PRO and Toshiba Exceria Type 1 and Type 2 cards performed slower than expected in the 6D compared with their performance in other cameras. Samsung cards were notably slow during JPEG burst shooting.
The 6D is limited by a relatively small buffer and modest write speed. The largest difference between cards is observed after the buffer has filled, at which point further shooting is limited by the write speed of the memory card. Using our detailed test scene, the 6D could manage 7 frames RAW+JPEG, 13-15 RAW and 23-58 shots JPEG before the frame rate slowed. Faster cards were able to clear the buffer faster allowing more shots at full frame rate before the buffer reached its threshold. Continuing to shoot for the remainder of time after the buffer filled, the fastest card provided 1.3 fps, while the slowest card provided 0.6 fps in RAW mode. In JPEG with the buffer full, the range was 3.24 fps to to 1.5 fps. No card was able sustain more than 1 fps in RAW+JPEG mode after the buffer had filled.
The number of shots and frames per second in continuous shooting depend on camera settings as well as the scene. More detailed scenes create larger files and reduce the number of frames and frame rate in an extended burst shooting test. The actual numbers in continuous shooting (including "buffer capacity") vary with camera settings and different image subjects.
The fastest SD card for the Canon 6D is the SanDisk Extreme Pro 95MB/s UHS-I. Both the 64GB and 32GB cards tested provided the top write speed and greatest number of shots in 30 seconds. The Extreme Pro is capable of over 90MB/s write speed, but the 6D does not reach anywhere near the write speed potential of this card.
From a value perspective, SanDisk Extreme 60MB/s SD cards provide nearly the top performance in the 6D at a much more reasonable cost. Both 32 and 64 GB capacity cards performed nearly identically. The Kingston Class 10 UHS-I 64GB SDXC card provides great speed for its price and supports a faster read speed (97 MB/s in benchmark tests) compared with the Extreme 60MB/s. Other notable value cards for the Canon 6D include the Patriot EP Pro, Transcend 95/60 and PNY Elite Performance 64GB SDXC.
The 6D has a built-in USB 2.0 port that can be used to download pictures from the camera. USB 2.0 connections are typically limited to 35MB/s, and the transfer speed measured in the 6D was slightly lower. Using the fastest SanDisk Extreme Pro 95MB/s UHS-I card in the 6D, the average transfer speed was 24.8MB/s downloading RAW images using a USB cable.
A separate USB 3.0 card reader can provide much faster transfers. The same SanDisk Extreme Pro card can provide around 90MB/s actual download speed copying RAW files to a computer. See the Card Reader Reviews for reviews and speed tests of several card readers.