PDA

View Full Version : D90 required SD card speed for 720 vid and burst shots



kingfisher29
13-07-2010, 1:49am
Hi,

bought a D90 on sunday, the sales person has throw in a 2G card and it's only got a 45X rating.

So I was testing the 720p video and burst shots, when playing back the video on computer it's all laggy and the burst shots felt like there's a bottleneck somewhere.

i'm guessing the card is too slow for the camera and can't keep up. so i'm wondering what speed rating do i need that can handle the 720p video and burst shots on a D90??

i've notice some ratings comes in numbers like 45X, 200X and some comes in class, like class 6, class 10.

so what are you guys(D90 owners) using?

rellik666
13-07-2010, 9:46am
The x# is the write speed, I don't think this would affect the output from your computer, unless you are running the video directly from the card?

It would only affect the speed at which the camera can collect information.

Roo

judybee
13-07-2010, 10:00am
I just bought a D90 and bought a class 10 card with it. Somebody told me to get a class 10 card as my other class 4 would be too slow. Not sure if this was right, but the class 10 has workded great so far, although I've not used it for video yet.

Watchamacallit
13-07-2010, 10:58am
I personally wouldn't run anything off the camera - if I'm doing anything with photos (or video) I'd copy it over first. The reasons are there are just too many possible choke points going along (just to name a few):

Camera CPU
USB (I'm just assuming, could be firewire)
CPU USB 1.0/2.0 slot
CPU Load
Ram Usage
Page file usage
Etc, etc


I was using a class 6 on my D90 and had no issues with it at all, on video or burst shots - I did try a class 2 to test it out at some point and that was really slow, so I would recommend on staying at a certain level.

maccaroneski
13-07-2010, 11:13am
Things that will affect burst mode on a D90 include the format that you are shooting (i.e. shooting raw you will find a bottleneck faster than shooting JPEG). Other things include the amount pf processing in camera. For example, turn Active D-Lighting off, as well as any in camera noise reduction.

I think that you may be finding in burst mode that it is the camera buffer filling that creates the bottleneck as opposed to the card speed.

Kym
13-07-2010, 11:49am
For the sake of a few $ its better to get the fastest memory card you can.
Class 10 is the go, and get a good brand - i.e. Sandisk.

Kym
13-07-2010, 11:49am
For the sake of a few $ its better to get the fastest memory card you can.
Class 10 is the go, and get a good brand - i.e. Sandisk.

kingfisher29
13-07-2010, 4:13pm
the video was copied over to the computer and played from the computer, and it was laggy. my computer hardware is fast enough to play 1080p video no worries. so it's was as if the memory card cannot keep up with the camera.

if i lower the image size and set to jpg mode for burst shots, it's better, but still needs to buffer a bit after 6 shots or so.

so i think i'll buy a faster SD card.

thanks for alll the fast replies

JD90
16-07-2010, 1:01pm
Don't put to much faith in speed x rating. That only indicates capability of short bursts and not sustained read/write speed. There is no standard on the x rating and really isn't a good indication of the overall cards performance

The card class is the rating that you want to take notice of. It is quoted to a set standard

eg class 2 = sustained/continuous minimum speed of 2 mb/sec
class 10 = minimum continuous speed 10 mb/sec

go with the fastest class if you want continuous high speed read/write because you will probably always find that you fill the D90 buffer.

JD90
18-07-2010, 10:09am
just to add to the above and answer you question, the write speed from the D90 seems to max at about 20 mb/s

reaction
19-07-2010, 1:36pm
class 6 will do video fine, but may as well get class 10 for burst shots.
class 10 is actually only 10 mb/sec on an EMPTY card with contiguous writes. it doesn't guarantee real life stuff.

and the 45x speeds are all lies. You know because you'd get these 200x 15mb/s cards that are labelled class 4. Because the 200x 15mb/s all have 'up to' in small print at the back, and are for READ speeds not WRITE.

I've been using Transcend cards for ages w/o problems, if all cards were free I'd consider the sandisk extreme 30mb/s edition (which tests at only 22mb/s!). All other sandisk cards are class 4 or 6 only.

kingfisher29
24-07-2010, 4:15pm
thanks guys for all the replies, i've end up bought a class 10 card, and now i don't seem to be having any problems.

will know what to get from now on.

cheers