A 64GB SD card can be bought online for around £30.
A Secure Digital (SD) card is a small data storage device that can be used with digital cameras and camcorders, MP3 players, cell phones, tablets and computers. To find the best SD card for you, consider what size and storage capacity you need. SD cards come in a variety of sizes. You'll need one that fits the device you're using and the type of card reader that's built in. SD, SDHC (SD High Capacity) and SDXC (SD Extended Capacity) memory cards are all 24 mm x 32 mm x 2.1 mm. Mini-SD cards are 20 mm x 21.5 mm x 1.4 mm. Micro-SD cards are 11 mm x 15 mm x 1 mm. An SDXC card typically requires an adaptor to fit into an SD or SDHC slot, but SDXC slots usually accept SD and SDHC cards. The storage capacity of SD cards typically ranges from around 2 GB to 32 GB, although larger-capacity cards are available for some devices. Format. First, you need to find out what kind of card your camera uses. The two important formats are Secure Digital (SD) and Compact Flash (CF). Most cameras use a version of SD cards, either plain old SD, SDHC or SDXC. SDHC stands for High Capacity—meaning between 2 and 32 Gigabytes. I now have a Canon EOS 6D that uses SD cards. I have a SanDisk 64Gb Extreme PRO 95MB/s speed class 10. I LOVE it. At mid-size RAW and jpg images, I get approximately 2700 shots on this card. And can take some pretty excellent HD videos that I do at my kids choir functions at school. 1 Most DSLR cameras will work best with the SanDisk Extreme and the SanDisk Extreme Pro varieties of SDHC/SDXC memory card. 2  All SanDisk SD and microSD memory cards are water-proof, temperature-proof, shock-proof, and x-ray-proof. 1 The Extremes also record Class 10 video, which is Full HD.For the photo hobbyist who is simply looking to enjoy their DSLR, consider the SanDisk Ultra memory cards. 2  After you choose what type of card you wish to obtain, you must then decide what capacity you need. SD cards are cheap. Don't forget you'll need at least one lens for the DSLR-if you can't afford a couple dedicated SD cards for your DSLR, maybe you should reconsider. I believe you'll need at least a class 10 card for recording video, but do check the specs of the camera you're purchasing. The following is a list of approved memory cards for the Nikon D3100 Digital Single Lens Reflex camera. These cards have been tested and approved for use with the D3100. The D3100 uses listed SD, SDHC, and SDXC memory cards. Memory cards with an SD Speed Class rating of 6 or faster are recommended for recording movies. Movie recording may stop unexpectedly when memory cards with lower Speed Class rating are used This article will walk you through picking the right SD memory card for your camera. It can be tricky and confusing to pick a card that works for you, much less the best card for your situation. Use this resource to assist you in your search for an optimized photography experience. 1 The Extremes also record Class 10 video, which is Full HD.For the photo hobbyist who is simply looking to enjoy their DSLR, consider the SanDisk Ultra memory cards. 2  After you choose what type of card you wish to obtain, you must then decide what capacity you need. 1 Check the compatibility with your camera and ensure that the memory card is a good fit for you and your camera. 2  Remember, all SanDisk SD and microSD cards are water-proof, temperature-proof, shock-proof, and X-Ray proof. 1 The Extremes also record Class 10 video, which is Full HD.For the photo hobbyist who is simply looking to enjoy their DSLR, consider the SanDisk Ultra memory cards. 2  After you choose what type of card you wish to obtain, you must then decide what capacity you need. 1 If you own a DSLR camera, you must decide how high of a performance quality you might need. 2  For the serious photo enthusiast, we recommend the SanDisk Extreme Pro memory card, which records in Ultra High Speed - 1, the highest video quality available in SD/SDHC/SDXC cards. 1 The Extremes also record Class 10 video, which is Full HD.For the photo hobbyist who is simply looking to enjoy their DSLR, consider the SanDisk Ultra memory cards. 2  After you choose what type of card you wish to obtain, you must then decide what capacity you need. Flash memory cards for digital cameras are now absurdly cheap. A 64GB SD card can be bought online for around £30. That’s enough space to store 5,000 raw files produced by a typical DSLR – or upwards of 30,000 JPEGs. These cut-price cards come with a caveat, though.  You probably have the wrong SD card or it needs to be reformatted. You can't record HD video on your DSLR without the right SD card. Whichever brand you chose, Transcend, SanDisk, Lexar, or any other, no matter the brand you need to pay attention to its speed. For HD video with a DSLR you need class 6 or higher card. I like to use class 10 cards as they seem to be the best balance between price and speed. But you can record video on your DSLR camera with a card as low as class 6. 
http://www.walmart.com/c/kp/sd-cards http://www.craftsy.com/blog/2014/06/digital-photography-memory-cards/ http://www.wikihow.com/Choose-the-Right-Sandisk-SD-Card-for-Your-Camera http://www.dpreview.com/forums/thread/3798758 https://support.nikonusa.com/app/answers/detail/a_id/16921/~/approved-memory-cards---d3100 http://www.wikihow.com/Choose-the-Right-Sandisk-SD-Card-for-Your-Camera http://www.wikihow.com/Choose-the-Right-Sandisk-SD-Card-for-Your-Camera http://www.wikihow.com/Choose-the-Right-Sandisk-SD-Card-for-Your-Camera http://www.alphr.com/features/380167/does-your-camera-need-a-fast-sd-card http://www.youtube.com/watch?v=He1IEm34AHQ
how much are sd cards for dslr