Article was released in Hotshoe, spring 2005             http://www.photoshot.com/

What you see is what you get!!

The digital darkroom has taken over from the wet lab bringing with it a series of new challenges that professional photography businesses have to overcome if they are to continue to service their client’s needs in a professional and profitable manner. In the first of a series of articles, colour management specialist, Udo Machiels, takes HotShoe through the first steps of how he created a digital darkroom using the Epson 4000 pro printer for London based Universal Pictorial Press & Agency.

“When I met Charles Taylor, managing director of UPPA, he had recently taken the decision to shut down the company’s 3,500 square feet of wet darkrooms. For almost 75 years UPPA, as one of the country’s leading press photo agencies, had supplied hundreds of prints every day to the nation’s newspapers out which their picture editors would make their daily selections, but the new digital age had put an end to this requirement. However, as UPPA is also the photographer of record at high profile events from which the important subjects require suitably high quality prints – such as the introduction of new peers to the House of Lords - Charles still needed a high quality print solution. Hence his call asking me to build him an appropriate “digital darkroom.”

In a digital darkroom, just like in a traditional darkroom, there are substantially two issues – one, quality of the prints and secondly, workflow. In this article, I describe how I set up UPPA’s inkjet printer so that Charles and Garry Dunn, head of production at UPPA, could be sure that they would get high quality prints, good enough for a Lord!

As a print device, Charles had already chosen the recently launched and positively reviewed Epson 4000 pro. This is a professional, desktop printer that uses 8 pigment inks (including 2 blacks) giving it a rich and fine colour range, and can produce prints up to A2 in size at a pretty decent print rate. Not a bad choice given UPPA’s dual requirements of high image quality and print size flexibility.

However, if you are running a professional photography business, it is extremely unlikely that you can just unpack your printer, plug it in and get perfect prints first time, every time. This isn’t necessarily a bad reflection on the machine; professional printers employ very sophisticated and sensitive ink laying technology causing out of box performance to be affected by a variety of factors including local conditions and to vary from batch to batch when manufactured. Depending on your level of tolerance, you may or may not be able to live with these raw results. Both Garry and I decided that we could and should improve on the UPPA’s printers out of the box performance.

The first step in increasing the 4000’s performance was to make a print of a digital file called a “target” and which contains “reference files” using one of the 4000’s out of the box printer driver “media type settings”. The first question was which Epson printer driver media type setting should we use? Maybe “Matt Heavy weight” or “Premium Gloss Photo paper” and a setting like “No Colour Adjustment.” For the technically minded, printer driver media type settings are actually pre-defined “linearizations.” In practise, you make several test prints using the same setting on different types of paper.

Not surprisingly, you need a special type of machine and some software to supply this target print and reference file and then to measure and to calculate the difference between the measurement taken from the printed target and the reference file. The more sophisticated – and generally the more expensive – the measuring tools4, the better your reading, and ultimately, the more colour accurate your prints will be! Having gone through this process what we had now achieved was a setting – a colour profile5 – where we knew that we would get an accurate print, within the limitations of present technology, of any digital file that we cared to print out on the machine. In fact, what we did was to set up several different profiles for different types of paper with the whole process taking just over half a day.

In theory, once you have created a profile you don’t have to do anything else to ensure that, in the words of the title of this article, “What you see is what you get” when you press the “print” button. As Charles commented, “We could use a black and white monitor to view our images, knowing that they will now come out properly when printed!” Indeed they would, but wouldn’t it be nice if you could see on screen an accurate representation of what will be produced by the printer? The thought of this got Garry Dunn, head of production at UPPA, even more excited, “No more test prints and wasted paper AND you can play around on your images whilst seeing what you will get!” – but that is another step which we will cover in the next issue of HotShoe.




1.A “target” is a digital file that represents a grid of colours where we already know the digital definitions (what we call a reference files) of each of the colours represented in the target. Therefore, by measuring the difference between the colours of our print (the printed test target) and the original target (reference file), we can find out how accurately our printer is reproducing colour at different printer driver settings.

2. Different Printer Driver Media Type Settings lay down various amounts of ink. Different papers absorb different amounts of ink. In order to find the best Printer Driver Media Type paper Setting for printing the test chart, and later to be used with the ICC Profile, we first have to print the same test chart on the same kind of paper using the various settings available in the printer driver. What we are looking for is the setting which gives us the best smooth tonal transitions even before we use a profile at all. Why? The better the linearization, the less work the ICC Profile has to do, and the more the ICC Profile is used for the ultimate fine tuning of the colour- balance.

3. A linearization is a command to the printer to lay down a predefined amount of ink and also controls the linear behaviour of each CMYK channel so as to ensure that the colour shading is smooth. If, for example, of any of these channels behaved in a very non-linear way, shadow detail may be clogged and we might lose high-light detail.

4 I use soft-and hardware supplied by GretagMacbeth - The ICColor chart reader and Spectrolino with the SpectroscanT table is the hardware and the software is ProfileMaker Pro 5.0 which calculates the ICC profiles using the measurement file and the reference file.

5 A colour profile is a small item of software, which is always working in the background to provide reliable and predictable colours from original to monitor to print. It describes the colour reproduction characteristics of a device specific colour space like scanners, monitors, and printers. It is a look-up table that describes the properties of a colour space and defines the most saturated colours within this colour space. The 'International Colour Consortium' (ICC) definition of a Profile is 'a digital data file in a standardised format, containing numerical values, which define the complete colour gamut of a device such as a camera, scanner, display or printer'.

Atmos Design / Udo J. Machiels is a specialist digital colour management consultancy. Services include: Setting up digital studios:- calibrating hard-ware, building ICC Profiles and setting up Rips, on-site with additional training if needed; RGB remote profiling for Epson printers and drivers. (See www.atmosuk.com); Advice on digital imaging from capture to final print.
Customers include photographers, businesses involved in Fine Art reproduction and pre-press companies. Other customers are ink, media and software manufacturers asking who ask Udo to test their products. Contact e-mail: info@atmosuk.com.