UDMA 101 - What is UDMA and why do I need it?

UDMA (Ultra Direct Memory Access)

Chris Wood, Delkin's Senior Digital Design Engineer, explains, "The advantages of UDMA over previous transfer modes are the use of double edge clocking. That means data is transferred on both the rising and falling edge of the clock. This not only doubles the data transfer rate per clock, but also results in increased reliability by the use of cyclical redundancy checking (CRC) for data transferred over the bus."

What does that mean? It's like going from pedaling a bike from only one side (standard CompactFlash, or CF) to pedaling a bike from both sides (UDMA CF). This new technology accelerates data transfer; dramatically increasing transfer speeds, allowing for a more streamlined workflow process. It's important to note that UDMA technology is ONLY utilized when used in combination with UDMA enabled devices, such as Delkin's FireWire 400/800 reader, All-In-One USB 2.0 Reader, the ExpressCard54 CF adapter, or the CardBus32 UDMA adapter.

Do UDMA enabled CF cards work with all CF compatible devices?

Yes.
For example, racing fuel will work in your rusty 1986 Datsun, but it will perform much better in a race car. We like to say that you can only work as fast as your slowest device. So, if your card reader is UDMA enabled but your CF card is not, you can only transfer images as fast as the card will support. By the same token, if the card is UDMA enabled, but the card reader is not, you can only transfer as fast as the reader will support.

You need both a UDMA enabled CF card and UDMA enabled card reader to take advantage of the additional speed and performance from UDMA enabled devices.

Why do I need UDMA technology?

How do professional photographers process their workflow with UDMA?

Professionals use UDMA enabled CF cards and UDMA enabled card readers and/or adapters together to transfer images to a computer.

When using UDMA enabled CF cards, professional photographers will always use an adapter or reader that is UDMA enabled, rather than transfer directly from the camera. Transferring directly from the camera has many disadvantages including: additional battery power loss, slower transfer times, and the inability to use the camera during transfer.

How do professional photographers process their workflow with UDMA?

Although most cameras are not UDMA enabled, you still get faster than standard CF processing by using CF UDMA enabled cards.

Manufacturer	Product	Available
Canon	EOS-1Ds Mark III	Yes
Nikon	D3, D300	Yes
Delkin Devices	CompactFlash PRO UDMA 305X	1GB, 2GB, 4GB, 8GB, 16GB
Delkin Devices	Readers	CF FireWire Reader, All-in-One USB 2.0 Reader
Delkin Devices	Adapters	ExpressCard54 CF, CardBus32 UDMA

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