We get alot of people ask us what the difference is between a Class 4 SDHC memory card and a Class 6 SDHC memory card. We thought we would enter this blog post to help customers when piurchasing a new SD card.

There are currently 3 speed classes for the SDHC (SD 2.0) specification. SDHC memory cards are used in most digital cameras and camcorders these days. The different speed classes are:

Class 2, Class 4 and Class 6. The numbers indicate the minimum sustained read and write speed requirements in mb/s.

There are not many of the Class 2 cards about these days so most of the cards that we stock are either Class 4 or Class 6.

The speed of a memory card can have the following implications:
1. A faster memory card means less time to wait between shots as the camera can process the data faster.
2. A faster memory card will upload the data faster to your pc, so less time to wait for the egg timer on your computer.
3. The speed of the memory card can affect the playback of data. For image files a Class 4 card should be more than adequate but if you are playing back large high definitionn video files then you may encounter playback lag with a class 4 card which is why we would always recommend a class 6 card for HD recording

For digital camera users a class 4 card should be more than adequate in most cases but if your camera has features such as multiple burst where many photos are taken in quick succession then a class 6 card may be more suitable as the data will be processed much faster. If you are shooting images in RAW mode then again we would recommend a Class 6 card as RAW files are much larger than standard JPG files.

If you are using a memory card in a digital camcorder we would usually recommend a class 6 sdhc memory card. Video files tend to be much bigger than image files so a faster card is beneficial for faster processing and playback. If your camcorder records in HD again a class 6 card is recommended. We also stock Video HD SDHC memory cards that have specifially been designed for HD recording.

We thought we would post this quick guide to show you some of the current most popular types of SDHC memory cards.

There are alot of SDHC memory cards available in different sizes and speeds so hopefully the info below will help you decide which is the right memory card for you.

SDHC memory cards start at 4GB capacity and are available up to a massive 32GB. They are used in the majority of new digital cameras and camcorders (apart from Sony branded devices which use Memory Stick Pro Duo). They come in 3 three main speed ratings – Class 2, Class 4 and Class 6. The speed ratings are the minimum sustained read/write speeds in mb/s. Most SDHC memory cards are either Class 4 or Class 6.

Class 4 SDHC memory cards. We would recommend a Class 4 memory card for most digital camera users that intend mainly to use the camera for taking photos and non-HD video recording. A Class 4 SDHC memory card will process data perfectly well in all types of camera even with very high Mega Pixel ratings.

Class 6 SDHC memory cards.Class 6 SDHC memory cards must have a minimum sustained read/write speed of 6mb/s. Many brands of cards will have the minimum 6mb/s speed rating but some brands such as Lexar and Sandisk produce memory cards that operate at much higher speeds than the minimum required. We would recommend Class 6 SDHC memory cards for all digital camcorder users and also digital camera users that want less time to wait between shots and any camera/camcorder user that intends to shoot in HD (High Definition).

Video HD SDHC Memory Cards – Many manufacturers now produce SDHC memory cards that have specifically been optimized to record in HD. These are usually Class 6 speed specification and have been produced with the HD user in mind. These memory cards will also take photos perfectly well but they have been produced with the guarantee that you wont experience things such as playback lag when playing back your videos. Most normal Class 6 memory cards will record and play High Definition video but the video HD cards have been branded as such to help the buyer looking to buy a memory card for HD purposes.

Sizes:SDHC cards starts at 4GB and go up to 32GB. For any digital camera user intending to use the memory card solely for taking photos a 4GB will usually suffice as this will give the user capacity for over 800 full size images on a 10MP camera.
For anybody wishing to record video on the memory card we would recommend at least an 8GB card as video files are much larger than photo files thus use more of the capacity on the card.
For HD video users we would recommend either an 8GB, 16GB or even 32GB card. HD video files on average use twice as much capacity than a standard video file.