Photo How To

Have you ever wondered about the difference between compressed and uncompressed Raw files, or asked yourself if there’s really a difference at all? If the answer is “Yes,” the video below is for you.

British photographer Dave McKeegan says the above question is one he gets all the time. To introduce this quick tutorial he says, “Today we’re taking a look to see what differences there are, if any, between uncompressed and compress Raw files, and how all this affects your photography.”

McKeegan says this topic has become particularly controversial since the recent introduction of the Sony A7 IV. That’s because this new full-frame mirrorless camera only attains 10fps bursts when shooting in compressed Raw, while delivering six fps uncompressed Raw files.

This discrepancy doesn’t particularly bother McKeegan, because he rarely shoots bursts in the uncompressed Raw mode. Nonetheless, he takes a close look at the pros and cons of the two Raw formats to see if there are any other advantages and disadvantages worth considering.

During the comparison, McKeegan provides side-by-side shots, to see if you can discern anything significant. He begins by explaining that cameras from one manufacturer may handle Raw files differently than those of another brand. For this informal test, McKeegan compares compressed and uncompressed Raw files from his Sony A7 III.

As McKeegan explains, “An uncompressed Raw file is all the information from the sensor, wacked into a file and slung on a memory card, whereas compressed Raw files compress the data down.” As you may have guessed, the main benefit of the latter is smaller file size. With McKeegan’s A7 III, that means 48MB for the uncompressed files, and only 24MB for the compressed.

With that out of the way, McKeegan moves on to the meat of this episode; namely what all these means with regard to image quality. So take a look at the comparison and see if you agree with his conclusions.

You can find more helpful tips on McKeegan’s YouTube channel and in another tutorial we posted, explaining how changing one Lightroom setting will turbocharge the editing process and and save you tons of time.