komputerbay 64gb writing speed

[stagsy]

Whilst it's sure to be on here somewhere - it's not been found, despite searching, reading and searching some more - so forgive the dumbass questions -  here goes...

What is the official minimum write speed required for a 64gb Komputerbay 1066 card for shooting raw on a Mk3?
Does one test for speed by doing the 5 min benchmark test in move mode with global draw off, then calculating the average from the 8 writes speed listed?
How does a "below minimum speed" card affect any attempt to record RAW e.g. constantly skipped frames, corrupted downloaded files, freeze, no record etc?

Thanks for any help with this

[chmee]

http://www.magiclantern.fm/forum/index.php?topic=12630.0

bet, you will find it.

[stagsy]

Nope

[dmilligan]

I'm going to re-word your question a bit, I hope this is what you were intending to ask:

What is the official minimum write speed required for a 64gb Komputerbay 1066 card for shooting raw on a Mk3?

The answer to that question would be: it depends on the resolution and FPS you're using. The required speed for a particular resolution and FPS can be easily calculated:
Width * Height * FPS * 14 / 8 / (2^20) MB/s

How does a "below minimum speed" card affect any attempt to record RAW e.g. constantly skipped frames, corrupted downloaded files, freeze, no record etc?

You have the option to either stop after a frame is skipped or to keep going, skipping frames. There shouldn't be any crashing or corrupted data as a result of a slow card. You could stick an old 2 MB/s SD card in there and you would still be able to record for a couple of seconds at 1080p. Any card speed below the one calculated using the above formula will not be "continuous", instead, you will record until the camera's internal buffer memory fills up at which point frames will start skipping or recording will stop, depending on the option you selected.

[stagsy]

Thanks dmilligan

Would hope to shoot at leaf at 1920x1080 or highest res possible at 25fps.

Your formula might be easy to calculate but not to read beyond what seems like W x H x FPS.......

[Audionut]

http://lmgtfy.com/?q=1920+*+1080+*+25+*+14+%2F+8+%2F+(2%5E20)

[chmee]

1920*1080[px] *25[fps] *14[bitdepth/pixel] /8[bit] /1024[bytes] = 88593.75[KByte/s] /1024 -> ~88 MByte/s
or
(1920*1080*25*14)/(8*1024*1024)
or
(1920*1080*25*14)/(2^23)
or
1920*1080*25*14/8388608

[stagsy]

Thanks guys for the ever so slightly smug replies but how come you both got different results to the same formula i.e.
Audionut 86.51 compared to chmee's 88?

[Walter Schulz]

88593.75 / 1024 = 86.51
Not quite 88. Rounding differs by less than 2 percent.

[dmilligan]

http://en.wikipedia.org/wiki/Mebibyte

[chmee]

i wrote ~88MB, because of not calculating /1024, but only moving the comma (/1000) (my fault, edited above)