Sometime ago my friend Oskar approached me with the results of an experiment that was mind blowing. He ran an experiment which enlightened me regarding the aspect of working with JPEG format files that drastically impacts image quality.
At the core of Oskar’s observation is that when working with a JPEG file, in many programs (potentially even Photoshop), each alteration made will prompt a save in the program before you manually pursue a final save of your changes. The end result is not just one round of data loss due to JPEG compression when you save your final version of an image, but several rounds of data loss reflecting the number revisions made before your final image is saved.
JPEG Compression: Data Loss & Image Impact
Check out the results with images. It might just blow your mind too and drive home why working with lossless formats (PSD, TIFF & RAW+Sidecar Files) are so critical.
[tags]JPEG, compression, lossless, image format, Photoshop, data loss, image quality, RAW, TIFF[/tags]
Thanks for sharing this, Jim! Although Oskar’s tutorial doesn’t make it clear whether each individual alteration prompts an automatic resave and loss in quality, even if that’s inaccurate, it’s always good to keep in mind that JPG is a lossy format. We’re better off sticking with lossless ones.
Just to clarify: The image was saved, closed, re-opened, saved, closed, re-opened…