Most photographrs have probably heard about 8-bit vs 16-bit images, yet not thought about it very much. Those are two very small numbers, and they’re not very far apart either! However, the truth involves some staggering numbers, that are “miles” apart! This is why it is extremely important to understand how image bit depth works.
The simplest explanation is this: the number of bits will define how many total possible tones and colors an image can display. An 8-bit image will be able to display a little more than 256 shades of gray, which translates to 16 million total color possibilities. (That is, if you are talking about 8 bits/channel on an RGB sensor.)
A 16-bit image, on the other hand, has the potential for 65,536 shades of gray, and will therefore be able to display over 280 trillion colors! Now you see how staggering the difference is. Simply put, 16-bit images appear lifelike and realistic, whereas 8-bit images might appear is if they are from some digital Minecraft-esque realm. Yikes! If you’re a photographer, you want your tones and colors to show smooth transitions.
As a visual representation of how big the difference can be, check this out: Nathaniel Dodson over at tutvid explains what the benefits of higher bit images in his visual breakdown.
Color depth, also known as bit depth, is very important to present photographs as you intend for your target audience, whether in print or on a digital display. The greater the bit depth of an image, the greater the number of colors and tones that you have in the image, which makes tonal transitions appear smoother.
Also, you have more to play with in post-processing! Remember that the bits increase, the number of colors increases exponentially. For example, a 1-bit image has two colors, a 2-bit image is 4 colors, and an 8-bit image has 256 colors per channel of red, green and blue.
What does this bit depth stuff mean in reality? It means that your images have much more “lattitude”. That’s a fancy way of saying that you can do things like recover lost shadows or highlights with ease! In fact, the dynamic range of many cameras raw files these days is truly incredible, with 4-5+ stops of shadow detail recovery being possible.
There is a caveat to higher-bit images, and that’s the fact most modern consumer displays don’t take advantage of the full gamut, only displaying about 16 million colors anyway.
RAW versus JPG | It’s All About The Bits!
One of the most hotly debated arguments in the earliest days of digital photography was, of course, RAW VS JPG. Actually, it all comes down to the bit depth! JPG images are only 8-bit, while raw images are 16-bit. (Well, there’s a big asterisk there about raw images, which we’ll get to next.)
This is why a JPG image can look beautiful straight out of the camera, but it will “fall apart” if you try to edit it. Simply put, the JPG image just doesn’t have the range of tones to withstand anything more than the slightest bump to contrast or saturation, before you start to see the transitions get, well, “chunky”.
For this reason, we always recommend that all photographers shoot in RAW, or RAW+JPG. You just never know what you might want to do with your photos later in post-production! Even if you hardly ever edit your images and the JPGs look beautiful on the back of your camera and/or your phone, raw files just don’t take up that much extra space, especially with raw compression and bit depth options today.
Raw Image Files | 12-Bit VS 14-Bit?
Wait a minute, I thought we were talking about 16-bit images? What is this about 12-bit and 14-bit images? Well, here’s the sort-of-bad news: most digital cameras that have a raw file capture are, in fact, just using sensors that are only outputting 14-bit images.
This is okay, because as soon as you open up these raw files in, say, Adobe Lightroom, you’re doing everything in a 16-bit environment. This “working environment” concept is crucial to why 8-bit vs 16-bit is so important to understand. Simply put, think of it this way: the more you “aggressively” edit your photos, the more you’re going to need the smoother, fine grade tools with which to do that editing.
In fact, some cameras (mostly Nikon) allow you to bump the raw files down from 14-bit to 12-bit, which saves even more space! This isn’t advisable for most photographers, but for those who capture extremely high volumes of images, such as action sports, wildlife, or time-lapse video, it can be a great way to save a ton of space on memory cards.
16-Bit VS 32-Bit?
You might be wondering, if 16-bit images are so good, is there something even better? The answer is yes! Adobe Photoshop allows you to go even bigger, to 32-bit images. Is this really necessary, though? Nope, it is not at all necessary for most photographers’ workflows. If you’re editing hundreds or thousands of photos each week, just stick with the native 16-bit workflow that Lightroom, Camera Raw, and most other raw processing software offer.
If you’re making absolutely enormous prints of images that you applied very heavy, strong edits to, then once in a while you can utilize the 32-bit space for certain special images, such as for gallery exhibitions.
8-Bit VS 16-Bit | Conclusion
To sum up, the best thing you can do as a photographer is to think about your images’ bit depth as a working environment. As such, it is important to avoid reducing your bit depth at any point during the editing process. Also, it doesn’t hurt that much, whether your particular camera is creating 16-bit, 14-bit, or even 12-bit raw files; the biggest difference you’ll see in image quality will absolutely be whether you’re using raw or JPG.
With that being said, hopefully you now understand that it’s all really quite simple! The powerful concept of 8-bit vs 16-bit images is something that, for most photographers, just does its magic silently in the background of your capture and editing workflow.
