Which memory card for your DSLR?

The Sandisk Extreme Pro 64GB Class 10 280GB oer seciond SDXC card

Need for speed? That 280MB/sec rating may not be the number you are looking for.

When you think about your camera and your memory card needs, do you think bigger and faster is better? Wait a minute..not so fast. Some cameras cannot handle newer SDXC formats, some cameras cannot take advantage of the 128MB/sec read rates or faster, and sometimes smaller and slower win the day.

My example..I have and still use a Nikon D90. It works, takes great photos and works with all of my lenses so why not right?

Well the first thing to note is that I shoot in RAW format, meaning NEF files for the Nikon (Canon uses a CR2 format, Panasonic uses a generic RAW format) are going to be a different size as you get more megapixels. So my D90 takes RAW photos in about 10-11 megabytes per image. While my D7100 uses a 28 megabyte raw image. Your camera has a common raw file size average and you should know it.

Now…for my D90, I never use anything bigger than a 16GB SDHC card. Sure it will support a 32GB card but I get into a grey area I try to avoid.

If I have 28 GB worth of images on the card and it fails, I am going to be mad. However if I only have 7-10GB of photos on card, I will still be angry at the loss but it won’t be nearly as bad as with 32GB. See?

Now a word about speed. Most cards will put their fastest speeds on the card and that is usually the speed a device can READ from it. What you want are cards that sync up with your camera speed. If you shoot at 7 frames per second and have a 90MB/sec write speed on your card, you might be able to eek out a few more shots before your camera’s buffer for the number of images it can hold, runs out.

So..ignore that 250 MB/sec listing on the card and look up the write speed for that card. Odds are it is going to be less than the read speed for that card.

That’s a quick lesson. If you have questions, please let me know. Next time, the quickie lesson will be over picking lenses to take on a trip.