You probably have seen the option in your editing software or your printer driver to choose 16-bit color processing. In fact, you may have selected the option, although you weren’t quite sure what it meant, because more data should result in better prints, right?
This short article will unlock the mysteries of 16-bit printing and help you to take full advantage of this feature in your imaging workflow.
16-bit is a fairly cryptic term. To better understand it, think back to your first computer classes where you learned about binary encoding. At that time, you probably learned that each piece of data could be defined with 8 binary digits consisting of zeros and ones. This is 8-bit processing, and it has been the standard format for describing data until relatively recent innovations in processor speeds and color rendering have made higher color fidelity practical for personal computing.
When we are talking about color, 8-bit processing consists of 8 bits of data per color channel. The red, blue, and green values of each pixel in your image would have their own 8-bit description.
In many cases, 8-bit data is sufficient information to describe the color in your image. But, in some instances, the limited descriptions available in 8-bit data will cause two pixels that are slightly different in your image capture to be defined as the same color in your output. This can result in an area of flat color in your print. Most often, you will see this type of effect in gradients or areas that move from light to shadow quickly.
“Okay, I’ve got it! I’ll always choose 16-bit and I’ll have smooth color transitions!”
Not quite, 16-bit data does have a serious disadvantage - file sizes are twice as large. This might be a great choice when your workflow is completely contained in one location, but it makes things harder when you have to transfer files or store them offsite. 16-bit data also takes longer for your printer driver to process, and, in many cases, the quality that you gain may not be visible to the average observer.
Second, taking a file from 8-bit to 16-bit actually risks degrading the color fidelity of your original image. If 16-bit information does not already exist in your file, your imaging software or printer driver will have to interpolate that information, basically making the best mathematical calculation available to create additional data points. In some cases, small rounding errors in this interpolation can result in color shifts.
The best way to figure out when a 16-bit workflow adds value to your images is through experimentation. Select a few RAW or 16-bit images that represent your style. Print them at your typical output size and keep track of the difference in printing time.
Look at your sample prints from a normal viewing distance for their size. For example, a wall-sized print should be viewed from a few feet, while a print that is sized to go into an album should be viewed about 18 inches away from your face. Once you have done these tests, you will have a clear understanding of the types of images and output sizes that benefit most from 16-bit processing in your own workflow.
16-bit processing is a powerful feature that can help you achieve high color fidelity in your imaging workflow. When implemented correctly, this function will help you to achieve lifelike color rendition from capture to print.