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MartinC
03-27-2007, 02:04 PM
I have just bought a Transcend 4GB SDHC Class 6 card for my L1 and can report the following write speeds compared to my Dane-Elec 1GB 133x SD card. The L1 will write 6 RAW+SHQ jpeg's in a sequence before the buffer fills up. Following the procedure suggested here http://fourthirdsphoto.com/vbb/showthread.php?t=5416 I started the stopwatch at the actuation of the first shutter release and stopped it when the camera stopped writing to the card.

Dane-Elec 133x 1GB SD card: 16.2 seconds
Transcend Class6 4GB SDHC card: 15.9 seconds

Given that 1 RAW+1SHQ jpeg is 19.2 MB, this corresponds to 7.4 MB/sec for the Transcend card and 7.3 MB/sec for the Dane-Elec card.

Martin

MartinC
03-27-2007, 02:16 PM
The above method assumes that the camera starts writing to the card as soon as the first shot in the sequence is complete. If in fact it waits until the end of the sequence, then it takes just 13.9 seconds to write the 6 RAW+JPEGS to the Transcend card in which case the write speed should be 8.5 MB/sec.

Martin

tspore
04-26-2007, 12:07 PM
I found a 4 GB card which will work in the camera. It appears that some companies (maybe its the photo stores) are repackaging 4 GB SD cards into 4 GB SDHC boxes, and those do not work.
I have a variety of SD cards that I bought to test read/write speeds with the L1 - SanDisk UltraII 4 GB SDHC - Hoodman 150X Raw 2 GB, SanDisk Extreme III 2 GB.
I shot all 3 cards till I filled the buffer (6 shots with Raw+lowest quality Jpeg)
All three of the cards wrote to the card in approx. the same amount of time. (There was .03 seconds difference between the three cards)
They all too from the time that it showed writing till the time of completion 14 seconds.
My guess is that all three cards are probably faster than what the camera can write. (Or maybe in the case of SanDisk II vs III maybe it can write as quick as the II but cannot for the version III)
The 6 shots take up 87.2 MB (The raw file size is 14.4 MB, and the Jpeg 128 KB It seems that the camera only records Raw & Jpeg, no Raw only feature)
So it write approx. 8.5 MB/sec with any of the 3 cards.
But really there is little value to go from SanDisk Extreme II to III's because write time is approx. the same time.
However, write time from the card to the computer will be faster.

MartinC
04-27-2007, 05:16 AM
Tony,
What class of SDHC card is the Sandisk Ultra II? These things come in three flavours: Class 2, 4 or 6 with the numbers referring to the minimum sustained write speed guaranteed by the card. My card is a class 6 but if you are getting similar write speeds from a lower class card then this might save someone a few bucks/quid.
Thanks
Martin


I found a 4 GB card which will work in the camera. It appears that some companies (maybe its the photo stores) are repackaging 4 GB SD cards into 4 GB SDHC boxes, and those do not work.
I have a variety of SD cards that I bought to test read/write speeds with the L1 - SanDisk UltraII 4 GB SDHC - Hoodman 150X Raw 2 GB, SanDisk Extreme III 2 GB.

tspore
04-27-2007, 11:07 AM
The 4 GB SanDisk Card is a Class 4.