CF cards

[arnica]

Hi All,

Just quick one for you CF card users out there. I've been looking at these type of memory cards and wanted to know the difference between a 16GB Ultra II Compact Flash CF (30Mb/s) and 16GB CF Extreme 16 GB G (60Mb/s) card.

At first glance the obvious difference is the read/write speed. Besides that why would someone want to purchase the 60Mb/s card over the 30Mb/s card? and in what instances would one card be advantageous over the over?

Is it worth spending the extra money for the 60Mb/s card?

[ricktas]

read write speed is it. Think of sports photographers photographing fast action. They may take burst shots of 10-20 photos, the faster these can be written the the card, the better. Also faster cards can be read at a faster rate. Ever sat and waited for 16gb of files to be transferred from a card to your PC? Wouldn't it be great if that could be quicker? Well it can be with a faster card.

Remember though that the camera read/write speed and your card reader read/write speed affect the overall speed result.

[TEITZY]

As far as I know the max write speed for Nikon bodies is about 30 mb/s, so having a card with greater than 30 mb/s is not going to give you much better write speed in camera, but obviously much better performance with card readers.

I think there is also some other enhancements with the Extreme cards versus the Ultra cards they use to justify the higher cost.

Cheers
Leigh

[jbee]

Glad i searched first, i was just about to post the same question as there is such a variety of cards and prices. Does anyone know what the max write speed for a Canon D7 is? As there is not much point in me buying one faster than that for a huge amount of dollars more.

[bigdazzler]

The SanDisk Extreme III series cards are great. Ive flogged the hell outta mine and not one has ever failed me.

[JorgD]

Arnica, I am pretty sure the extreme CF cards have better temperature and pressure tolerances than the Ultra series. So if you are taking photos in extreme temperature conditions, I would buy the extreme card just to be sure.

I use an Extreme III card rated at 30 MB/sec and and Extreme card rated at 60 MB /sec. When I got the Extreme card, I wanted to see how much faster it really is compared to the Extreme III card, so I ran some tests at my PC with my USB card reader. The 30 MB/sec card was faster than the 60 MB/sec card.

This result was of course slightly disappointing, so I started doing more research on this, starting on the Sandisk web page. It appears as they their wording and testing procedures changed over time. The Extreme III card has a through put of at least 30 MB/sec, the Extreme card has a throughput of up to 60 MB/sec. Looks like the words "at least" and "up to" actually cross over for me.

Doing further research, the 60 MB/sec card uses an UDMA interface rather than the PIO interface of the older cards. Now, unless your card reader can make full use of UDMA (which mine obviously could not), you will end up with no better and possibly worse performance than the older cards.

Testing both cards in my 7D shooting Raw images, both cards allowed 22 shots to be taken at high speed before the camera started to slow down. The stated buffer for the 7D is 15 raw. So from the cameras perspective there was no difference at all. Even shooting 1080p movie mode with the 7D, provided your card can accept at least 8 MB/sec, you will have no problem taking movies to your hearts content.

I recently purchased a Nexto Extreme external HD with card reader, and the Nexto could back up the images significantly faster from the 60 MB/sec card than the 30 MB/sec card, causing me to believe that it does make good use of the UDMA interface.

I personally would not spend a lot of money on a faster card as the camera can't make use of the faster speed and the USB 2.0 interface is also slower than most cards so you won't see any benefit there. The only time there is a benefit for higher card speed is if you have a UDMA enabled backup device like a Nexto, or if you have a UDMA CF card reader connected to Firewire 800 or USB 3 when it is released.