CompactFlash vs CFast vs XQD Memory Cards

September 21, 2016

by Robert Giordano

Searching the internet, I found a lot of outdated information comparing CompactFlash to the newer CFast and XQD card formats. CompactFlash memory cards were developed way back in 1994 by SanDisk but they still work fine, even in high end cameras. Unfortunately, the design of CompactFlash limits their speed to 167 MB/sec for UDMA7 cards. This becomes important when you're shooting UHD or 4K video.

I thought I would look at the best cards in 2016, how much they cost, and what cameras use them.

CompactFlash Cards
One of the best CompactFlash cards offered today is the SanDisk Extreme PRO CompactFlash Memory Card.
- Capacity: up to 256GB
- Read Speed: up to 160MB/s
- Write Speed: up to 140MB/s
- Cost: roughly $300 for a 256GB card, $150 for a 128GB card

I should point out that write speed is the important number because that's what matters when you're recording video. Some card manufacturers advertise the read speed while the write speed is much slower.

Cameras using CompactFlash:
- Canon 1D C, CompactFlash only
- Canon 1D X, CompactFlash only
- Canon 1D X Mark II, (1) CFast slot, (1) CompactFlash slot
- Canon 5D Mark IV, (1) CompactFlash slot, (1) SDXC slot
- Canon 5D Mark III, (1) CompactFlash slot, (1) SDXC slot
- Canon 5DS, (1) CompactFlash slot, (1) SDXC slot
- Canon C500, (1) CompactFlash slot, (1) SDXC slot
- Canon C300, (2) CompactFlash slots, (1) SD slot
- Nikon D800, (1) CompactFlash slot, (1) SDXC slot
- Nikon D4S, (1) XQD slot, (1) CompactFlash slot


CFast Cards
Released in 2012, the CFast 2.0 specification supports SATA-III with bus speeds up to 600 MB/sec, compared with the CompactFlash limit of 167 MB/sec. CFast cards are similar in size and shape to CompactFlash cards but they are not compatible. CFast is based on the Serial ATA bus (SATA), rather than the Parallel ATA/IDE bus (PATA) for which all previous versions of CompactFlash are designed.

Sandisk appears to lead the market with their Extreme PRO CFast 2.0 Memory Card:
- Capacity: up to 128GB
- Read Speed: up to 515MB/s
- Write Speed: up to 440MB/s
- Cost: roughly $370 for a 128GB card, $210 for a 64GB card

Cameras using CFast cards:
- Canon 1D X Mark II, (1) CFast slot, (1) CompactFlash slot
- Canon C300 Mark II, (2) CFast slots, (1) SD slot
- Canon C700, (2) CFast slots, (1) SDXC slot
- Blackmagic Design URSA Mini 4.6K, (2) CFast slots
- ARRI Alexa Classic, requires the XR module upgrade
- ARRI Alexa SXT, requires CFast 2.0 adapter


XQD Cards
The format was first announced in November 2010 by SanDisk, Sony and Nikon. XQD cards are based on the PCI Express 1.0 interface (PCIe) and support bus speeds up to 500 MB/sec. XQD version 2.0 was announced in June 2012, featuring support for PCI Express 3.0 with transfer rates up to 1000 MB/sec. This card has the potential for capacities up to 2TB. Currently, XQD cards are made by Sony and Lexar but not by Sandisk.

Optimized specifically for their PXW-FS7 XDCAM Cinema camera is the Sony 128GB XQD G Series Memory Card:
- Capacity: up to 128GB
- Read Speed: up to 440MB/s
- Write Speed: up to 400MB/s
- Cost: roughly $170 for a 128GB card, $115 for a 64GB card

Cameras using XQD cards:
- Sony PXW-FS7, (2) XQD slots, (1) SD slot (for config)
- Sony PXW-Z100, (2) XQD slots, (2) SDXC slots
- Nikon D5, (2) XQD slots
- Nikon D4S, (1) XQD slot, (1) CompactFlash slot
- Nikon D500, (1) XQD slot, (1) SDXC slot


Conclusion
I'm having flashbacks to VHS vs Betamax. The CFast cards cost twice as much as the XQD cards and are only slightly faster (440 MB/sec vs 400 MB/sec write speed). The CFast cards are also used in more cameras but I guess it depends on what you're shooting. XQD looks like the better format because it has a greater potential for expansion and its cheaper! We'll just have to wait and see what happens. For now, my CompactFlash and SDXC cards are working fine.





Return to All Blog Posts >