10 mega-pixel digital cameras that can shoot short video clips are quite common these days. One is often required to use the digital camera in burst mode. SD cards are quite handy when you go to cover a big event or on a vacation where you do not have your computer with you to offload pictures as they were taken. With SD cards, you store your images on them until you access your computer for further processing the images. Most digital cameras come with slots for SD (Secure Digital) and SDHC (Secure Digital High Capacity) memory cards. You should note that mini-SD card and micro-SD card are smaller versions of an SD card usually made for mobile phones. You may not be able to plug them into your digital camera without an adapter. Some digital cameras support MMC cards that are not as widely available as SD cards. Read your digital camera manual carefully to know which card types is supported.
Once you know about the type of cards that are supported by your digital camera, the next thing you should consider is the storage capacity suitable for you. It is better if you calculate your requirements and choose appropriate SD card within your budget. Else, you will run out of space on your memory card in the middle of a photo shoot. The latest digital cameras are capable of taking pictures in a variety of formats (RAW, AVI, JPEG etc) and resolutions (640x480 to 3648x2736). When you multiply number of formats with the range of resolutions, you get many combinations at which you can capture images or video. You need to have some idea regarding the resulting file sizes for various combinations. Lower resolution pictures result in smaller file sizes. RAW images produce larger files than JPEG files. For example, a 3648x2736 image at full 10 MP resolution results in approximately a 15 MB file in RAW format, 30 MB in BMP format and 2.2 MB in JPEG format. Please note that these values may vary for different digital cameras. When the same digital camera is dialed down to take a 2048x1536 image (3.1 mega-pixels), it produces a 4.7 MB RAW file or 9.4 MB in BMP format or 1 MB in JPEG format.
When you are about to capture video you have to consider frame rate in addition to resolution and format. Videos captured at 30 fps (frames per second) are double in size compared to videos shot at 15 fps. Video formats include motion JPG, AVI and RAW. You may also capture audio along with video. For full information about video capturing capabilities of your digital camera, refer to its manual. When calculating SD card size required, take into account how many pictures you usually take at a time in which format and resolution. If you are planning a video, try to determine approximate length of the video, frame rate and resolution. For your reference a 2GB SD memory card can store 20-40 minutes of video ( based on mode ) or 770 photos at 3648x2736 ( 10 MP ) resolution or 34 hours of MP3 music at 128 Kbps. A 4 GB SD Memory card holds just double of that. Again, these figures may vary for different digital cameras.
Whatever is your requirement, whether it a video or photos, remember you can always use several smaller capacity SD cards and just change them when they are full. It does not take much time switch memory cards, so do not panic if you do not have a large memory card. It may be a good practice if you use separate SD memory cards for separate formats. Then you can estimate how many more photos you can store in the remaining space.
Jaya Kumar Patchala is a digital photography hobbyist. Click here to buy the latest in SD memory cards in India
