8-bits and 16-bits vs. 32-bits

The difference between 8-bits color and 32-bits.

Every photographer talks about taking pictures in a «raw-format» because the image has much more information to work with, but what are really the difference? Why is 32-bits images better than 8-bits or 16-bits?

I won’t use the time to explain what a bit is. It’s the computers way to calculate things. In images this is quite important. The bits is (in a nutshell) how much information there is in the picture.

An 8-bits image got a color range from 0 to 256. That means that each color (red, green, blue) has 256 variations. Roughly 16.8 million colors to work with. Not bad, and every .jpg-picture is actually 8-bits.

16-bits images has 65 536 possible values per color. In other words 281 trillion color possibilities! This is far mor colors than the eye is capable of seeing, but in the editing process, more information is never a bad thing.

So why is there 32-bits? 32 bits is actually 24-bits color and 8-bits of non color information. Instead of a range between 0-255 or 0-65 536, 32-bits images uses the values between 0 to 1. 0 is black and 1 is white. But (and this is the big but), the image can actually contain values lower than 0 and higher than 1.

If you try to adjust the colors in 8-bits or 16-bits images, the black cannot get any darker than 0 (black), and the whites cannot get any brighter than 256 or 65 535 (white). But in the real world, there may be things that is actually «brighter» than white or «darker» than black. For example a lightbulb, a flashlight or the sun. You cannot get this information from an 8-bits or 16-bits image.

This is where 32-bits comes into action. 32-bits images contains an extra 8 bits with this light-information. In other words, like a dream to work with compared to 8-bits images, and destined to give you great results!

The only downside, is that there is no camera to date that has the capability to take a picture in 32-bits. A single lens reflex camera has the maximum of 16-bits. But if you make a HDR (High Dynamic Range Image), this image has the possibility of 32-bits. And if you work in 3D or with user created content in a graphical software like Photoshop or After Effects, you may create images (or video) that has the 32-bits information.

And maybe, one day the real world is ready for real 32-bit images.

8-bits image vs. 32-bits HDR-image (see the difference around the sun):