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View Full Version : is d90 video limited by slow SD cards?



nihilus
09-18-2008, 09:41 PM
I'm a total newb looking to get a D90 as a first time DSLR right now, mainly for still image photography but here I am on this forum so I must be interested in the video capabilities as well right? :-)

I'm wondering how slow an SD card you can get and not have the video capture fail? From people talking about video file sizes..

600MB in 5 minutes is 600MB/300s = 2MB/s average

So I assume class 6 (6MB/s) cards will never be bandwidth limited for video?

There's lots of class 6, 16GB SDHC cards out there. I'm not really keen on paying more for the 30MB/s transfer rate. For the price of one 16GB SanDisk Extreme III card, on newegg you can get 3 class 6, 16GB SDHC cards.

I can't quite find this question answered around the net yet.. Can anyone confirm that video will not be bandwidth limited on the D90 at all, as long as you get a class 6 SD card?

Am I right to assume that the real bandwidth limit is 4.5 still shots per second in RAW format.. which is something that only sports photographers need to worry about. I'm only concerned with running the D90 for multiple minutes in video capture mode, and getting the most flash card GBs for my $, not with how fast it takes to unload the SD card to a computer.

Also.. beware products like this:
http://www.newegg.com/Product/Product.aspx?Item=N82E16820171349
it says 15MB/s but it is actually rated class 4, with 4MB/s sustained write speed.

stoiqa
09-18-2008, 09:44 PM
please do a search before starting a new thread

http://www.dvxuser.com/V6/showthread.php?t=146898

THX

ando
09-19-2008, 02:29 AM
the class rating is about minimum sustained speed for writing
your card may go much higher, there is no rating for maximum speeds, read or write.

for example since d80 has a ~10MB/s write speed a sandisk III was recommended
http://www.robgalbraith.com/bins/multi_page.asp?cid=6007-8531