Hi Radim,
In relation to Transcend and MxR, which version of MxR do you have? Is it the newer or older one?
With Transcend – a few days ago…I started re-testing Transcend 16GB (with the red stripe) class 6 and did the unthinkable…and stopped and started recording with the red light still on, (I did this around 20 times)…to see if I could produce a media error. Believe it or not, it didn’t happen and all clips are playing fine in the clip browser and I then did the same test with SanDisk 16GB class 6 HD version and believe it or not, the same thing. It didn’t happen again. I’ll continue this process over the next few days to see if I can create a media error. Mind you, the environment is pretty cool with air con so temperature and humidity is not extreme. In the next test, I’ll film in high humidity and 35 – 40 degrees temperature to see if this makes a difference.
In regards to the difference in the class level of your SDHC memory card, class 10 or 6, with class 10 – you should be able to get faster write speed (average between 16 – 18 MB/s) whereas class 6 in Transcend – it may give you only 11.5 MB/s write speed.
SanDisk Extreme class 10 will give you on average 19 MB/s in write. So in general class 10 should be faster.
On EX1/EX3, the faster write times can improve over cranking eg SanDisk Extreme class 10 can achieve 52 fps sustained…which is probably the limit for EX1/EX3 USB 2.0 interface.
On EX1R, that interface is improved and you can achieve full over cranking with a SDHC memory card which writes at around 12 MB/s…so as you can see, speed is not everything…
eg. I’ve recently been testing a new company’s class 10 memory card, where originally the sample card sent, would not work with the new MxM or Hoodman and the older MxM, however, the company wants the memory card to work, so they sent me a sample of the same card with different firmware. The results were that the camera was able to format and record to it and it is a class 10 memory card which gives writing at 17.6 MB/s.. but the problem we are having is media errors… and this class 10 card (sample), it is not able to over crank at all! But they will keep sending me new samples with new firmware, until they get it right.
So, what you are looking at is, the firmware which needs to be rock solid to start with. The instability of firmware will contribute to the frequency of media errors.
I hope this helps or sheds some light on your situation.
MxM Express