Article ID : 00257862 / Last Modified : 24/12/2021Print

What is the difference between uncompressed RAW, lossless compressed RAW and compressed RAW images

    IMPORTANT: This article applies only to specific products and/or operating systems. Check Applicable Products and Categories for details.

    What is compression in photos?

    Compression in itself relates to a reduction. Compression in photography is the process of reducing the size and quality of your photos. There are several reasons photographers opt for compression. The most common being to optimize your storage space.

    Compression lowers file size by reducing colour, contrast, and sharpness from your images.

    Uncompressed RAW:

    An uncompressed RAW file preserves all of the data in an image without compression. As all image data is stored with no impact on quality, you have the freedom to manipulate aspects of the photo like brightness, colour, sharpness and noise reduction with minimal quality loss.

    The main drawback to uncompressed Raw files is their larger file sizes. If you opt to shoot in this format, it is advisable to use an SD card with a high storage capacity or to capture and store your images elsewhere to free up space. 

    Shooting in Uncompressed Raw is recommended when both high image quality and developing speed are required. This format allows for faster processing using development software compared to lossless compressed RAW.

    Lossless compressed RAW:

    Lossless compression is a format that allows you to reduce image size without compromising on quality. A lossless compressed image is processed by post-processing software and the data is decompressed like a ZIP file. Decompression allows you to expand the compressed file back to its original size.

    This is a popular format that occupies less space with minimal quality loss. 

    Lossless Compressed Raw is recommended when you want to record content in a higher image quality equivalent to uncompressed RAW in a smaller file size format.

    Compressed RAW:

    Compressed RAW sometimes known as lossy compression, is a format that reduces the data in a photo. An image captured in Compressed RAW occupies less storage space. Once an image is stored in a Compressed RAW format it cannot be decompressed, meaning that the image will lose some of its data. Some

    photographers use this format to optimize storage space.

    Compressed RAW is recommended when you want to shoot continuously at the maximum speed or to limit the file size.