Sunday, November 15, 2009

Benefit of high speed flash memory cards?

Hello. I am wondering what is the TRUTH about flash memory cards. Will an SD card with higher speed perform better than ones at regular speeds? Is it true it'll help with flash recycle times and shutter lag? Is there a brand(s) you would steer clear from, or does it really matter? Seems like this one A-Data SD card I bought last year doesn't work as well as it should seemingly. Thanks in advance.

Benefit of high speed flash memory cards?
Here's an answer that I wrote for a specific application, but it will be useful to you in your buying decision:





The benchmark of 1X is a transfer rate of 150 KB per second.


I have not encountered a card that was not at least 4X (600 KB per second) and 12X (1.8 MB per second) is now a common speed for an unlabeled card. Compared to 4X, 12X might still be called "high speed" by some manufacturers. 40X is also a common "high speed" card and the transfer rate would be 6 MB per second. That's not too bad for most applications.





Sandisk Ultra II claims a minimum write speed of 60X or 9 MB per second, and a minimum read speed of 66X or 10 MB per second. Sandisk Extreme III claims a minimum write and read speed of 133X or 20 MB per second.





The largest 6MP photos on a D50 camera (for instance) seem to be about 3 MB, so it seems that an Ultra II could save 3 high data images per second, while an Extreme III could save 6 high data images per second. The D50 continuous mode gives up to 2.5 frames per second, so you could be gathering about 8 MB of data per second. If you do not have at least the Ultra II or equivalent, it is easy to see how the D50 bogs down at times.





Once the memory buffer is full, you can not save images any faster than the card can save them and the camera will stop taking pictures until there is space available in the memory buffer. This means you are limited by both the size of the memory buffer and the write speed of the card.





A faster card may indeed help with shutter lag, but probably only in a continuous shooting mode. I do not see any way that it could help with flash recycling time.





See also: http://www.lexar.com/dp/workflow/Pro_HS....
Reply:A fast memory card will do nothing for your flash recycle speed and nothing for shutter lag. These are limitations of the camera itself. Or actually, fresh batteries can improve the flash recycle time.


You might - MIGHT - notice a small difference if you shoot high resolution video or if you do a lot of continuous shooting. This is when you need write a lot of data to the memory card in a hurry - and this is the only time that the speed of the card matters. But even then, the bottleneck is usually the camera itself. Point %26amp; shoot cameras have pretty slow write speeds. Slower than a good memory card is capable of recieving.


Fast cards are intended for dSLR cameras. I use a Nikon D200. This camera can shoot 5 frames per second and every picture can be up to 16 MB. That means that I can throw 80MB per second at the memory card. 400MB in 5 seconds. The D200 can also write to the card like a banshee, so I invested in fast cards to keep up.
Reply:The way the speed was explained to me is that the download speed is increased. If you shoot in RAW format, then each picture will be a large file, and you'll want it faster, especially if you have a lot of pictures.
Reply:Faster cards will do nothing to help with shutter lag or flash recycle times. If you shoot rapid-fire bursts of shots they may allow you to work with more shots at a time.





I use SanDisk and a generic brand of CF regular cards (not high speed). And they both work equally well for me.
Reply:many good brands


it helps slightly


go for at least 50x faster


go to yahoo search


type sd memory card
Reply:The only real reasons to get a high speed card are if your camera has a rapid fire function and if you are using you camera to record video and you want the highest quality. It doesn't really help with flash or other functions. Other than that, a regular memory card is just fine. Sandisks are usually reliable.


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