The Sony A550 has two card slots, each using a different card format. The first memory card slot uses SD and SDHC cards. The other card slot uses Sony PRO-HG Duo and PRO Duo cards.
SDHC memory cards are usable, consequently, the biggest SD memory card that works is 32GB. The PRO Duo and PRO-HG Duo slot works with 16GB and smaller memory cards.
Only one memory card slot can be used at a time. There is a switch inside the card door is how you determine which memory card slot to record to.
PRO Duo memory cards are a proprietary memory card format owned by Sony. Because of this, SD memory cards are cheaper and can provide greater performance than PRO Duo memory cards.
In a hurry? My recommendation is to get this SD card in the A550:
64GB or larger cards are not compatible with the camera.
Looking for a new lens for your camera? Go look at the 6 Best Sony A550 Lenses.
Best SD Cards
SanDisk, Lexar, and PNY are brands that produce the best Memory cards. The best memory cards I have owned have been the SanDisk Extreme Pro cards.
That does not mean you need to purchase a card made by SanDisk for your Sony A550. Look for cards with impressive names. That will ensure you get fast read/write speeds, shock resistance, and other features.
I have not had errors with Lexar Professional or PNY Elite Performance SD cards.
The issues I have experienced with cards has been when I have used cheap generic brands. Not having a brand name increases the chance of data corruption or card errors.
If you are looking to spend less, don't buy a generic card. You will be better off purchasing a high-quality SD card with a smaller capacity.
Recommended SD Cards
- Best value for the money.
- Capacities from 16 GB to 128 GB.
- Transfer speeds up to 80 MB/s.
- Class 10.
- High speed card.
- Capacities from 16 GB to 1 TB.
- Transfer speeds up to 95 MB/s.
- Class 10.
- High quality card.
- Transfer speeds up to 95 MB/s.
- Class 10.
Sony A550 SD Card Compatibility
SDHC and SD cards can be used in the Sony A550. Use a card to get the maximum overall performance out of the camera.
The brand new SDUC and SDXC cards can't be used with the A550.
Currently, there are four different specifications of Secure Digital (SD) cards. Newer card specs add tech that allows for larger memory capacity as well as increased transfer rates.
- Secure Digital (SD) - 128MB to 2GB.
- Secure Digital High Capacity (SDHC) - 4GB to 32GB.
- Secure Digital eXtended Capacity (SDXC) - 64GB to 2TB.
- Secure Digital Ultra Capacity (SDUC) - 4TB to 128TB.
SD Card Speed
The speed rating of an SD card is based on the sequential write and read speeds. The write speed of an SD card is essential for video in addition to continuous shooting.
Slows memory cards can decrease the number of continuous frames the Sony A550 can take. This is because the camera's buffer will not be able to write to the card quickly enough.
With video, a slow card can cause an unexpected end to shooting. The video file may also be corrupted. If you are going to shoot video, it is critical the memory card you use meets the minimum requirements of the camera.
Read speed is nice to have for transferring files to a computer. If you are filling up cards with images or video, a card with a fast read speed will save you time.
Speed Class Rating
A memory card is given a Class rating based on the sustained data write speed of the card. Class 10 is the top rating, even though memory cards can be purchased that are considerably faster.
Here you can see a list of the Classes and the applicable minimum transfer rates:
- Class 2 - 2MB/s
- Class 4 - 4MB/s
- Class 6 - 6MB/s
- Class 8 - 8MB/s
- Class 10 - 10MB/s or faster
Virtually any card worth choosing for the Sony A550 will be a Class 10 memory card. In the short time since the launch of the camera, Memory cards have gotten a good deal faster.
Ultra High Speed (UHS)
The Ultra High Speed (UHS) bus is found in SDUC, SDXC, and SDHC cards. The UHS bus cards to achieve increased read and write speeds.
There are three different specifications. They are UHS-I, UHS-II, and UHS-III.
Look at the label to find out the rating of an SD memory card. If there is a Roman numeral I, II, or III on the front of the SD memory card, that is the UHS rating of your SD memory card.
- UHS-I - Maximum transfer rate of 104 MB/s
- UHS-II - Maximum transfer rate of 312 MB/s
- UHS-III - Maximum transfer rate of 624 MB/s
Sony A550 PRO Duo Card Compatibility
One of the card slots can be used with PRO Duo and PRO-HG Duo cards. PRO-HG means that the memory card potentially has read transfer rates up to 50MB/s plus a 15MB/s minimum write speed.
Only PRO Duo memory cards that are 16GB or smaller will be compatible in the A550.
PRO Duo cards are usually near two times as expensive as an SD card. As a consequence of the added cost, I will not recommend purchasing a PRO Duo card to use in the A550.
Do Both Memory Cards Slots Need to Be Used in the A550?
No, the Sony A550 can not use both card slots concurrently.
Competing brands have cameras that can use both card slots at the same time. That provides additional features such as overflow protection, mirroring the cards, and splitting up RAW files and JPEGs.
Being unable to use both slots for additional features, means you don't need to spend more on a PRO Duo card.
Below is an approximate estimation of how many large JPEG images you can expect to store on each size of SD card.
- 4GB - 1,160 images
- 8GB - 2,320 images
- 16GB - 4,640 images
- 32GB - 9,280 images
Make sure to look at the specs for both SD and PRO Duo memory cards before you buy them. The SanDisk Extreme Pro 32GB is the best Sony A550 memory card.
Here are additional cameras with the same dual slot configuration: