What are the colour calibration recommendations for PDF to Book?
A calibrated screen is the basis for a reliable colour reproduction. To match your screen as closely as possible with our prints, we recommend a gamma value of 2.2 and D65 light condition. For a very basic calibration you can use standard tools on your computer like the calibration assistant under your screen settings. Here, you can adjust your screen in contrast and lightness. For a precise calibration, there are measurement tools available (hardware and software, e.g. from xrite or basICColor).
Different printing systems have different colour gamuts. Please note that there are colours on your screen which cannot be reproduced on the print. In the production, ICC output profiles make sure that you get the optimum colour from each printing system which is as close to the original colour as possible.
Due to the different technologies, photographic printers are based on RGB while digital printers are printing in CMYK mode. This explains the fact that the gamuts of these printing systems are different.
The standard working colour space of the lab is sRGB. Firstly, this is the best colour mode for photographic printers. Secondly, the lab can always apply the optimum colour conversion to CMYK for digital printers and for different papers and finishings. This happens within the production workflow. The colour specialists on site care about the colour management of the printing systems.
Using the presets BobBooks_PDF.joboptions you make sure to create PDFs in the working colour space of the lab. During the layout process, you don’t have to care about the colour modes too much. RGB images from your camera don’t have to be converted. You are also free to insert images in other RGB colour spaces like AdobeRGB. The presets will make sure that all objects are converted to sRGB.
If you have used our PDF to Book software to launch your templates, then the Bob Books presets should automatically be installed.
The colour space of your screen is larger than the colour space of printers. The possibility to print exactly what you see on your screen is therefore limited. In addition improper settings and technically inadequate screens can lead to colour deviation.
The ambient light also influences the colour perception. So differences between your screen display and the printed colour is normal to a certain degree.
If you adjust your screen settings as followed you will get the best results:
Colour Temperature: 6500 Kelvin
Illumination: approx. 120-160 cd/mÇ (also dependent of ambient light).
160cd/mÇ correspond to an illumination level of 500lx.
If you have a measurement device (spectral photometer) and the respective monitor calibration software, you can also follow the instructions in your software. Your monitor allows you to change the settings of the colour temperature, contrast and brightness. Those settings are independent of your computer.
1. Adjust the colour temperature to 6000 – 6500 Kelvin
2. Maximize your contrast
3. Now decrease the brightness until the dark Q (left side of the image) is barely visible.
Also the light Q (right side of the image) should barely be visible.