Originally Posted by Isoprop
Tom, you are absolutely correct about the Kingston Class 4 cards. The results are more than dissapointing.
Results from CrystalDiskMark Random speeds with 512K block size using a 32GB micro SDHC card
Kingston Class 4
Read: 17.56 MB/s
Write: 0.688 MB/s
SanDisk Class 2
Read: 14.09 MB/s
Write: 5.175 MB/s
I got a total of 19 x 20min clips and 1 x 15min clip giving me a total recording time of 6hours and 35mins
. The clips have a data rate of approx. 10 Mb/s
I connected the camera to my PC to view the files. Everything went fine. Then I Safely Removed the camera from the PC. I then unplugged it - I did not turn off the camera first - maybe that was the problem.
The camera was now DEAD as a doormouse
When connected to a PC or a Power source, the red light lit for a few seconds but there was no way
that I could get the yellow light to show. I tried everything - 30 seconds reset with and without pressing other buttons, all sorts of combinations. Nothing, nada. After about 20 minutes I gave up and went to bed.
This morning, still nothing. I kept on pressing buttons and suddenly the yellow light came on and I could take movies and pictures
After about a minute I turned the camera off. And of course it was dead again
After more pressing buttons the camera came to life again, and since then has worked perfectly.
Firmware bug found
Has anybody else noticed that the date/time for each 20 minute clip advances by 2 HOURS
!! The date advances by about 39 HOURS for a six hour recording
- Not good...
I have sent an email to "Apple", so I wonder what she has to say
Wow! Your CDM random write speed for the SD 32GB CL2 card is more than DOUBLE that of the SD 4GB CL2 card. I guess the smaller architecture of the larger memory crammed into the same size package can really reduce the memory access time a lot! My CL6 Transcend 4GB card tests just a tad under the SD 4GB CL2 card. So for recording speed, the SD CL2 card is as good as any CL6 card I've seen tested yet, but for writing or sequential writing, the CL6 card is considerably faster.
I haven't seen that date stamp discrepancy on my consecutive 20 min. clips, but then my camera only records at an average of 7 Mbps, not 10 Mbps like yours, and my files do not save automatically when battery power is lost. I've brought "file save" problem to the attention of Apple, and partner Diana, since this will need to be resolves when they come out with the continuous recording feature soon. I also brought up the fact that some cameras routinely record at an average data rate of 10 Mbps rather than 7 Mbps, and they can only say the data rate varies with the images being recorded and the speed of the card. I agree with that... I've seen mine go up over 13 Mbps on an instantaneous basis, but for all the videos I've shot so far, they all drop to an average of about 7 Mbps. And I'm getting no dropped frames reported, so the speed of the card should not impact the average data rate of the recorded video as I see it. My card is capturing every thing the camera is outputting to it, and I'm satisfied with the lower data rate... quality is still very high, with more recording time on the card.
Could that camera problem you mentioned be a dirty or intermittant switch on the camera?