A 128GB memory card is a popular choice for photographers, but how many photos can it actually hold? The answer depends on several factors, primarily the image file format (JPEG or RAW) and the camera’s megapixel count. Let’s explore the storage capacity of different memory card sizes (32GB, 64GB, 128GB, and 256GB) and the variables that influence how many images they can store.
Overhead still life photography shot of a camera, notebook, pen, coffee cup and memory card
Understanding JPEG and RAW File Formats
The two main image file formats used in digital photography are JPEG and RAW. JPEG files are compressed, meaning they discard some image data to reduce file size. This makes them smaller and ideal for web use or sharing. RAW files, on the other hand, retain all the data captured by the camera’s sensor, resulting in larger file sizes but offering greater flexibility for editing.
JPEG: Smaller Size, Less Flexibility
JPEGs are the most common image format due to their smaller size. A 20MP camera will typically produce JPEG files ranging from 5 to 10MB, depending on the compression level. This allows for more images to be stored on a memory card. However, the compression process sacrifices some image quality and limits editing possibilities.
RAW: Larger Size, More Flexibility
RAW files preserve all the image data captured by the sensor, providing maximum detail and dynamic range. This makes them ideal for professional photographers who require extensive post-processing capabilities. RAW files from a 20MP camera are typically around 30MB each. This larger size means fewer images can be stored on a memory card compared to JPEGs. Each camera manufacturer has its own proprietary RAW format (e.g., CR2 for Canon, NEF for Nikon), while DNG is a universal RAW format.
Image of a camera and memory card on a white background.
Calculating Photo Capacity for Different Memory Card Sizes
Based on an average RAW file size of 30MB and a JPEG file size of 7MB, here’s an estimate of how many photos each memory card size can hold:
RAW File Capacity:
- 32GB: Approximately 1,092 photos
- 64GB: Approximately 2,184 photos
- 128GB: Approximately 4,368 photos
- 256GB: Approximately 8,732 photos
JPEG File Capacity:
- 32GB: Approximately 4,700 photos
- 64GB: Approximately 9,400 photos
- 128GB: Approximately 18,800 photos
- 256GB: Approximately 37,600 photos
Factors Affecting Memory Card Capacity
Remember that these are estimates. The actual number of photos a memory card can hold varies based on factors like:
- Image Resolution: Higher resolution images have larger file sizes.
- Compression Level (JPEG): Higher compression reduces file size but can impact image quality.
- Bit Depth: Images with higher bit depth (e.g., 14-bit RAW) have larger file sizes.
- Camera Model: Different cameras may produce slightly different file sizes.
Choosing the Right Memory Card
Consider your shooting style and storage needs when choosing a memory card. If you shoot primarily in JPEG and don’t require extensive editing, a smaller card might suffice. For RAW shooters or those who capture high-resolution images, a larger card is recommended. Factors like speed (read/write speeds) and card type (SD, microSD, CFexpress) should also be considered based on your camera’s compatibility and shooting requirements.
A SanDisk Micro Secure Digital SD 128gb memory card.
Conclusion: 128GB Memory Card Capacity and Beyond
A 128GB memory card can hold a substantial number of photos, ranging from approximately 4,368 RAW images to 18,800 JPEGs. Understanding the difference between file formats and considering your individual needs will help you choose the right memory card size for your photography. With larger capacity cards like 256GB and even 1TB now available, photographers have ample options for storing their valuable images. Remember to factor in aspects like shooting style, image resolution, and post-processing requirements to determine the optimal memory card size for your photography workflow.
