The Sony Alpha 900 features a dual card slot. I do not like to repeat myself, enough has been said about the extra functionality lacking on the card slot, still it is a miss for a camera of this class. Certainly for those who shoot in a combination of JPEG & RAW, a spreading of the storage formats would have come in handy. This time, with the Alpha 900 you will have to divide your pictures afterwards, which means you need a PC or notebook to do it. The card slot supports Memory Stick Pro Duo and CompactFlash memory cards. Officially, Memory Stick is supported up to 16GB; however, in practice I used the new SanDisk 32GB CompactFlash without a problem.
Memory Stick Pro Duo & CompactFlash memory cards
You will find yourself using a huge amount of GBs due to the high resolution of this Sony DSLR A-900. And it's quite an amount; 24 megapixels of resolution with a RAW file size of approximately 38MB. It is obvious a 2GB card will not take you far, in particular when you shoot in a combination of RAW+JPEG. You will have to deal with 50MB per picture, which comes down to around 300 pictures on a GB card. My advice is to use a minimum of 8GB storage capacity and if you really get going with photographing, purchase a 16GB card!
Considering 8GB of storage capacity:
24 Megapixels - ratio 3:2 - RAW - 38MB - 211 pictures
24 Megapixels - ratio 3:2 - cRAW - 26MB - 313 pictures
24 Megapixels - ratio 3:2 - RAW & JPEG - 49MB - 166 pictures
24 Megapixels - ratio 3:2 - cRAW & JPEG - 36MB - 224 pictures
24 Megapixels - ratio 3:2 - JPEG Extra Fine - 24MB - 343 pictures
24 Megapixels - ratio 3:2 - JPEG Fine - 10MB - 790 pictures
24 Megapixels - ratio 3:2 - JPEG Standard - 7MB - 1185 pictures
The table above considers a storage capacity on a CompactFlash memory card and a ratio of 3:2. Ratio 16:9 will mean a few more pictures, however, when shooting in RAW the camera always selects ratio 3:2.
SanDisk Extreme Ducati 8GB a fast memory card
Processing speed of the Sony A900 is excellent, especially since this is a 24 megapixel DSLR. If you compare the performance of the A900 to its rivals, the A900's performance is average. It's hard to compare these models, since most of them don't work with large files like the A900. I'd recommend purchasing a fast memory card with a speed of a minimum of 40MB per second. In combination with the SanDisk Extreme Ducati 8GB you will reach a high speed of 30-35MB per second, which suffices to keep the speed going.
Transferring files via a Firewire kaartlezer
If you hesitate to transfer files through the Sony A900 because of its speed, just try it once. The transfer speed is impressive and you won't feel the need for an external card reader. A card reader is handy if you want to avoid connecting the camera all the time, or want to be able to keep the workflow going whilst the memory card transfers pictures. A Firewire card reader would then be an excellent option.
Sony A900 comes with a Li-Ion battery
The Sony DSLR-A900 comes with a Li-Ion battery that is recharged through an external battery charger. One charge takes approximately 175 minutes and a full recharge of the battery takes about 235 minutes. According to CIPA measurements, which are standardized but not necessarily have to equal practice, a fully charged battery should deliver approximately 880 pictures; however, in practice this amount will not be reached. And if you think you need longer battery life, or want it just for convenience, you can purchase a second Li-Ion battery.