By Peter Ryan
Printing is one of the most enjoyable outcomes of photography but it is also one of the most frustrating and potentially difficult things to master. This paper is not about post processing techniques, just printing.
There is no use trying to print anything unless you have spent time calibrating and profiling your screen.
Calibrating is a hardware function and you can use the following website: – www.photofriday.com/calibrate
Profiling is a software function and it makes appropriate changes to your graphics card. Software packages such as Spyder3 and Colormonki (there are others) are used for this process and are a MUST.
Many people blame poor colour rendition on the ink, paper or printer but never on the screen. If you don’t do this first step then you have little chance of getting a reproduction that meets your expectations.
The next thing you need to manage is the output and the easiest way to start is to use the printer manufacturer’s paper and inks. When you load the printer driver software it will download ICC profiles to match the ink and paper combinations. When you get more experienced you may choose to use other papers and download specific ICC matching profile or make your own profiles – using special software.
The most common complaint I hear from people is MY PRINT IS TOO DARK.
Now you have calibrated and profiled your screen you need to turn the brightness of your screen down to 50%. The image on screen is backlit and if turned up too bright you underexpose the image during post processing to compensate.
Also remember, the image on screen is based on RGB (additive colours) while the print is CMYK (subtractive colours) and viewed under reflective light so you will never get 100% correct colour matching. Next you need to understand the output limitations of your desired medium.
The Digital Dynamic Range Conundrum
All the way through the output process colours are being ‘blocked up’ or compressed at either end of the dynamic range. The dynamic range of a jpg file consists of 256 colours each of the Red, Green and Blue channels. Combined these give you over 16.78m colours so you are not short on colours but there is only 256 tones between Black (0) and White (256).
With all this blocking up of colours what you find that while 0 (zero) is Black, 50 also looks black, 100 looks black and it is not until you get to the mid 100 tonal range you start to see shades of grey, so-to-speak. With the compression of colours from capture to output we finish up with a lot of detail that is hidden, particularly in the shadow area.
To get a good quality print that reflects more what the eye sees we need to open up the shadow detail by moving the tones from the area we cannot see to the mid-tone area where we can. We do this by using the Shadow/Highlights command (or Fill slider in ACR).
This process can make the image look a bit flat (or milky) so it is important to add some saturation of colour and bring in the Black and White clipping points on the Levels command to restore the proper contrast to the image.
Below is the full RGB colour spectrum.
There are two main colour spaces used in digital photography – sRBG and Adobe RGB (1998). The first is slightly smaller than the second. Gamut (or colour range) is the word used to describe the colour spaces.
What Colour Space do You Use?:
1. sRGB is best to use if you are printing direct from the camera or using kiosks and generally most photo labs are set up for sRGB – it is best to ask them first. sRGB is also the mode best suited to viewing on computer screens including email and web postings and is best for skin tone in wedding and portrait shots.
2. Adobe RGB (1998), or just Adobe RGB as it is called, has a wider colour range (gamut) and particularly in the green range. This is best used when you intend to do your own post production work in a designated photo imaging program, i.e. Photoshop, which can handle the larger colour gamut. This may give some slight advantage when printing to your own inkjet printer.