RAW file contents

What’s inside a RAW file?

What you see may not be what you got!

Here are histograms displayed by five different photo editing applications – all of the same RAW file.

Take a look:

The tools were set to their default settings. The same RAW file was loaded into each. No adjustments were made. Yet the displayed histograms are rather different. You can see that especially in the red channel. In three of the editors it seems that the reds are seriously overexposed. The data rises on the right side and there is a tall spike at full scale.

The last two are actually from one app and a sub-tool inside. Here the input file seems to be adequately well exposed with no, or very little, data lost to overexposure.

How can that be? Let’s look at a couple of JPG image files from two of these tools.

Again, no adjustments were made, and the images merely saved as JPG files.

You can see that the first one has very little detail in the bright red areas of the blossom. It looks “pasty”. The second image, although darker, seems to have good color detail in all areas.

The histogram displayed by the camera also showed that the photo was overexposed.

So the question is, was this image overexposed and irretrievably lost detail in the red-most areas? Or was there indeed red color detail there that the last tool successfully used in making the JPG image?

I will not identify the tools used for these illustrations, lest I have made some mistake that paints some of the tools in a “bad color”. Although you can easily get that information from what is shown here (just click on an image).

Your thoughts and comments are invited.

.:. © 2022 Ludwig Keck