As soon as I got my hands on a Canon 7D,the first thing I needed to upgrade were my media cards. My old 8gb Sandisk Extreme III CompactFlash cards were just not big enough nor fast enough to keep up with the 7D. Since I plan to experiment with HD video, I was planning on at least 16gb cards, but which ones? The wrong media card can create a bottle neck to slow you down and your next shot. With video, it can mean dropped frames and audio drop-outs.
Unfortunately, it is not as simple as comparing the listed speeds on the cards. It’s more like comparing apples and pineapples; they may both have “apple” in their name, but they are definitely NOT the same. There is no standardization involving the speed of the cards. A manufacturer’s speed rating is only a reference for that manufacturer. A 300x speed rating from SanDisk is not the same as a 300x from Lexar. So, what can you do?
Rob Galbraith DPI has completed extensive testing on most compactflash cards and sd cards. They have even tested these cards under “real-world” conditions by testing these cards in a variety of digital cameras. Take a look at an excerpt of the performance table for the 5D MarkII below:
Using this chart, I focused on the following CompactFlash cards:
- Lexar Professional 300X 16GB
- SanDisk Extreme IV 45MB/s Edition 16GB
- Transcend UDMA 300X 16GB
Each of these cards had virtually the same performance ratings which allowed me to focus on price and availability. Since the SanDisk cards also had a rebate, I decided on 16gb SanDisk Extreme IV. This card can hold almost 50 minutes of HI-DEF video or almost 500 RAW images.
I plan on testing the 7D this weekend and posting results next week.