What a JPEG file actually is
JPEG (Joint Photographic Experts Group) is a compressed image format that has been the standard for digital photography since the mid-1990s. When your camera records a JPEG, it captures raw sensor data, applies internal processing — white balance, sharpening, noise reduction, contrast curves, colour profiles — and then discards the original sensor data. What remains is a compressed image with the processing decisions already baked in.
JPEG uses lossy compression, meaning some image information is permanently discarded to reduce file size. A 24-megapixel sensor captures approximately 72MB of uncompressed data per frame. A JPEG from the same shot typically weighs 8–15MB depending on the camera's compression settings and the complexity of the scene. That 5–9× reduction in file size represents genuine information loss, not just reorganisation.
JPEG files open in every image viewer, web browser, and editing application without additional software. They can be uploaded directly to social media, shared by email, and printed without any intermediate step. For most casual photography, this is exactly what is needed.
What a RAW file actually is
A RAW file is the unprocessed sensor data from the camera — essentially the digital equivalent of an undeveloped photographic negative. The camera records what the sensor captured without applying any of the automatic processing decisions that produce a JPEG. White balance, picture styles, noise reduction, and sharpening settings recorded in the camera's menu have no effect on the RAW file's actual image data, though they are stored as metadata tags that editing software can read as starting suggestions.
RAW is not a single universal format. Each manufacturer uses a proprietary format:
| Manufacturer | RAW Format | Typical File Size (24MP) |
|---|---|---|
| Canon | .CR3 (current), .CR2 (older models) | 25–35MB |
| Nikon | .NEF | 25–50MB |
| Sony | .ARW | 24–48MB (lossless compressed) |
| Fujifilm | .RAF | 30–55MB (X-Trans sensor data is larger) |
| OM System / Olympus | .ORF | 16–22MB |
| Universal (Adobe) | .DNG (Digital Negative) | Varies; some cameras shoot natively in DNG |
RAW files require dedicated software to process before they can be viewed as finished images. They cannot be uploaded directly to most social media platforms or opened with the Windows default photo viewer without first converting them.
The editing flexibility difference — with concrete examples
The most frequently cited advantage of RAW over JPEG is "more flexibility in editing." In practical terms, this means specific recoverable adjustments that are not possible, or only partially possible, with JPEG files.
Exposure recovery
A RAW file from a modern full-frame sensor typically contains 13–14 stops of dynamic range. If an image is overexposed by 2–3 stops (highlights blown out), a RAW file allows recovering significant detail from those overexposed areas in software. A JPEG from the same shot, having discarded shadow and highlight data during compression, will show pure white in overexposed regions with nothing recoverable.
Shadow recovery is similarly more extensive. A correctly metered RAW file from a Sony A7 IV or Nikon Z6 III can have shadows lifted by 4–5 stops with acceptable noise levels. A JPEG lifted by the same amount shows visible banding and colour degradation.
White balance
White balance in a JPEG is permanently applied to the image data. Changing it in post-processing means shifting the colour values of pixels that were already processed with one white balance — which degrades image quality. In a RAW file, white balance is metadata only. Changing from daylight (5600K) to tungsten (3200K) in Lightroom or Capture One costs nothing in image quality because the underlying pixel data hasn't been processed yet.
This is the single most useful property of RAW for indoor photography. If you shoot under mixed lighting — part natural light, part fluorescent — a JPEG will show colour casts that are very difficult to correct cleanly. The same scene shot as RAW allows setting white balance to whatever colour temperature looks accurate after the fact.
Noise reduction
In-camera JPEG noise reduction is applied as a blanket process that smears fine detail to reduce the appearance of digital noise. Software noise reduction applied to a RAW file gives the photographer control over how aggressively noise is removed and where — preserving detail in important areas while smoothing uniform surfaces like sky gradients.
Software that handles RAW files
The three most widely used RAW processing applications are:
- Adobe Lightroom Classic / Lightroom (Cloud) — subscription-based (approximately PLN 50/month as part of the Photography Plan). Supports all major RAW formats. Non-destructive editing; all adjustments stored as metadata without altering the original file. The industry standard for photographers working in high volume (events, weddings, commercial shoots).
- Capture One — subscription (approximately PLN 130/month) or perpetual licence (approximately PLN 1,400 one-time). Known for colour rendering quality, particularly in skin tones. Preferred by fashion and portrait photographers. Has manufacturer-specific versions for Sony and Phase One users.
- Darktable — free and open-source, available on Windows, macOS, and Linux. Supports most RAW formats. The learning curve is steeper than Lightroom, but the feature set is comparable for still photography. Actively maintained with regular updates.
Manufacturer-supplied software (Canon's Digital Photo Professional, Nikon's NX Studio, Sony's Imaging Edge) is free and supports the manufacturer's proprietary RAW format, but these applications are generally less capable for batch editing and colour grading than the three listed above.
When JPEG is the practical choice
RAW is not the correct format for every situation. JPEG has genuine advantages in specific workflows:
- Sports and news photography: Cameras in burst mode filling a buffer — a Canon EOS R3 can shoot at 30fps for example — will buffer significantly fewer RAW frames than JPEGs. News photographers often shoot JPEG for the speed of delivery; the images go from camera to wire directly, with minimal or no post-processing.
- Storage-limited situations: A 256GB memory card holds approximately 10,000 JPEGs at standard compression versus 3,000–5,000 RAW files from the same camera.
- Immediate delivery: If images need to be available without any post-processing step — events where photos are printed on-site, for instance — JPEG from the camera is ready immediately.
- Well-controlled light: In studio photography with consistent strobe lighting and a fixed white balance, the advantages of RAW over JPEG narrow considerably. Many commercial photographers working in controlled conditions shoot JPEG for workflow speed.
Shooting RAW+JPEG simultaneously
Most cameras allow recording both formats simultaneously. This uses approximately 1.5–2× the storage space of RAW alone. The JPEG can be delivered or shared immediately; the RAW file is retained for cases where significant post-processing is required. For photographers who are uncertain whether they need RAW, this option provides a safety net at the cost of storage and slower memory card write speeds.
Bit depth: 12-bit vs 14-bit RAW
Many cameras offer a choice between 12-bit and 14-bit RAW capture. Bit depth determines the number of distinct tonal values the file can contain. A 12-bit file has 4,096 tonal steps per colour channel; a 14-bit file has 16,384 steps. The 14-bit file contains more gradation information, particularly in shadow areas, which is most visible when making large exposure corrections in post-processing.
The practical trade-off: 14-bit files are larger and require the camera to write more data per frame, which reduces burst shooting speed. Cameras like the Nikon Z9 and Sony A9 III, designed for high-speed shooting, often default to 12-bit in their fastest burst modes and require switching to 14-bit manually for static or lower-cadence work.
Further reference
Technical measurements of RAW dynamic range across camera models are available at DXOMark's camera ranking, which lists sensor dynamic range in stops. The Adobe Lightroom supported cameras list confirms which RAW formats are currently supported in Lightroom Classic.
