Originally posted by Kunzite Sorry, but this actually avoids my question.
Let's try again: I could get a Sandisk Extreme Pro UHS-II 270MB/sec (rated writing speed) or a Sony Tough 300MB/sec, or, at less than half the price, a Sony Tough rated for 150MB/sec write speed.
If anyone could do a test - I've seen the one with the Kingston 300MB/sec, so a 150MB/sec-ish card one would be great - that would be much appreciated.
See this video by yasso1967
They test the following SD Cards: Lexar 256Gb 1000X UHS-II Card, SanDisk Extreme Pro 128GB UHS-I card, ProGrade Gold 256GB V60 UHS-II Card, and the ProGrade Cobalt 256GB V90 UHS-II card. I do not know the manufacturer's claimed WRITE speeds for the cards. This is the rating that matters for capturing photos.
The Lexar 1000x card takes about 35 sec to clear the buffer
The SanDisk card takes about 19 sec to clear the buffer
The ProGrade Gold V60 takes about 16 sec to clear the buffer
The ProGrade Cobalt V90 takes about 20 sec to clear the buffer
They then run the ProGrade Gold again and it takes 20 sec to clear the buffer.
It depends on your use. If you just shoot 2-3 frames and then walk around for 20 min before shooting again, then any SD card will work for you. If you shoot bursts at 7fps, you might be just fine with 150MB/s cards. If you are constantly filling the buffer and missing shots while you wait for the buffer to clear, you might be best served by a V90 card.
Again, just because a manufacturer claims a given read/write speed, that is always under optimal conditions. Doesn't mean that the card will sustain that speed, either. A V60 card might clear faster than a V90 card - the V rating is for the minimum sustained write speed.
We'll know more as folks get their K-3 iii's and can test with different cards.