Image Formats: JPEG, TIFF, RAW, DNG

Image Formats: JPEG, TIFF, RAW, DNG

Every digital image you capture or create is saved in some file format. The format determines how the image data is stored, how large the file is, and what editing options you have. In photography, the four most common formats are JPEG, TIFF, RAW, and DNG. Each has a specific role in a professional workflow, and knowing when to use each one saves storage space and preserves image quality.

JPEG is the universal standard for sharing and displaying images. It uses lossy compression that reduces file size significantly by discarding information the human eye is less likely to notice. A JPEG from a 24-megapixel camera might be 5 to 10 megabytes, compared to 30 to 50 megabytes for a raw file. JPEGs are perfect for social media, email, web galleries, and any situation where you need to deliver images quickly. The trade-off is that every time you save a JPEG, you lose some quality.

TIFF is a lossless format often used in professional printing and publishing. It preserves all image data without compression artifacts and supports high bit depths and layers. TIFF files are large, often several hundred megabytes for a single image. They are not practical for everyday use but are the standard for archival masters and high-end print work. If you need to preserve every bit of quality for a print or publication, TIFF is the format to use.

RAW is not a single format but a category of proprietary formats specific to each camera maker. Canon uses CR2 and CR3, Nikon uses NEF, Sony uses ARW, Fujifilm uses RAF. These files contain the unprocessed sensor data and cannot be opened by most image viewers without specialized software. RAW is the working format for serious editing. You import RAW files into Lightroom or Capture One, edit them, and export to JPEG or TIFF for delivery.

DNG, or Digital Negative, is Adobe's open raw format designed to be a universal standard. Some cameras shoot DNG natively, and many photographers convert their proprietary raw files to DNG for archiving. DNG is smaller than most proprietary raw formats because it discards some non-essential metadata. It is also more future-proof because it is an open standard not tied to any camera manufacturer. For long-term archiving, DNG is an excellent choice.