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12-11-2009, 03:37 PM   #16
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According to the Wikipedia:

" SD Speed Class Ratings

SD Cards and SDHC Cards have Speed Class Ratings defined by the SD Association. The SD Speed Class Ratings specify the following minimum write speeds based on "the best fragmented state where no memory unit is occupied":
  • Class 2: 2 MByte/s - 13x
  • Class 4: 4 MByte/s - 26x
  • Class 6: 6 MByte/s - 40x
SD and SDHC cards will often also advertise a maximum speed (such as 133x or 150x) in addition to this minimum Speed Class Rating. Important differences between the Speed Class and the traditional "X" speed ratings are; 1) the ability of the host device to query the SD card for the speed class and determine the best location to store data that meets the performance required, 2) class speed defines the minimum transfer speed. Even though the class ratings are defined by a governing body, like "X" speed ratings, class speed ratings are quoted by the manufacturers but unverified by any independent evaluation process.
On 21 May 2009, Panasonic announced new "class 10" SDHC cards, claiming that this new class is "part of SD Card Specification Ver.3.0". Toshiba also announced cards based on the new 3.0 spec As of November 2009, the SD Association's Web site does not include information on this new class or new specification. "

There are now Class 10 SDHC being sold from Panasonic and Sandisk (Class 10 is supposed to be 10Mb/s minimum).

I have also seen Class 10 SDHC from Centon - that seem very reasonably priced.

Bear in mind that there are several SDHC that already claim 150x -
which is: 0.150 Mb/s x150 = 22.5 Mb/s -
however this is more likely only the (optimistic maximum) read speed (if that)
most of these seem to test out at about ~15 Mb/s read and ~7Mb/s write speed - which is actually plenty fast enough for almost any digicam.

Brands such as A-Data, ATP and RiData, OCZ, PQI, Delkin have 150x SDHC.

TopRAM also have 150x but for some reason they test out at about 15Mb/s Read - but less than 5Mb/s write........

The fast Read speeds are actually very useful -
as they allow for fast uploads to one's computer using a suitable Hi-Speed USB2.0 SDHC reader.



12-11-2009, 06:25 PM   #17
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Stick with quality cards like Sandisk Extreme if you don't want problems. A-Data SDHC cards are junk INHO.
Amazon.com: Customer Reviews: A-DATA 32 GB SDHC Class 6 Flash Memory Card 32GSDHC6 (Blue)

Amazon.com: Customer Reviews: SanDisk 16gb ExtremeŽ III 30MB/s Edition SDHC High Performance Card
12-12-2009, 09:25 AM   #18
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Yup stick with the tried and tested.. I recently upgraded from 8GB Sandisk Extreme III 20MB/s to 16GB Sandisk Extreme III 30MB/s SDHC! Both cards handled video on K-7 fine though

I shoot in DNG Raw format all the time, so files sizes are between 15-20MB per photo. 8GB Sandisk Extreme III 20MB/s SDHC stores around 323 DNG Raws with continuous shooting (Hi) mode for DNG Raw, I can shoot off 11-13 photos before the buffer is full. Now with 16GB Sandisk Extreme III 30MB/s SDHC it can store around 651 DNG Raws and with continuous shooting (Hi) mode for DNG Raw can shoot off 16-17 photos before buffer is full which is 30-54% faster it seems.
12-13-2009, 11:08 PM   #19
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Hi my partner uses LEXAR Class 2 cards in K-x and the video works fine

12-15-2009, 08:17 AM   #20
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All of my cards are either PNY Optima's or Lexar's. I have had good results from both without problems. I find the PNY's are noticably faster and very well priced at my local BJ's so that's all I buy presently. I should mention they are the 4gb SDHC variety. A pkg of 3 is currently 19.99.
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