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Let There Be Light - part 1 of 1 2 3 4 5

by Mike McNamee Published 10/04/2015

The most frequent query to come up at printing and colour management seminars is 'why are my prints darker than my screen?' This is an almost universal cry for uncalibrated system users and has the same underlying cause - the screen is too bright!

But this is actually only one side of the problem. Yes, your screen may be too bright, but your print viewing conditions are likely to be too dark, thus compounding the problem.

Now there is an international standard for this carry-on, called ISO 3664. This was published in the 70s and has had two revisions, one in 2000 and the latest ISO 3664:2009 was implemented in 2012. For the casual user, these things only serve to confuse matters still further. This is especially true because the standard's main target audience is printing press and press services. There is a standard set-up specified for viewing prints and (almost as an afterthought) for comparing prints against screen, soft proofs. The main thing that a press operator is concerned about is the match between a hard-copy proof and what the press is producing; throwing a monitor into the system only serves to complicate matters.

Despite these reservations there are some things to be gleaned and taken on board from ISO 3664. The illumination level of the viewing area should be at one of two intensities, according to what you are doing. These are called P1 and P2 as follows:


"P1 Critical comparison of PRINTS
This is recommended when comparing an original and its reproduction, or when comparing a sample print with a production run. The higher illumination level enables better judgment for evaluation of higher density zones (shadows). The illumination
level is 2,000 lux at print level.

However, it is also recommended to make a comparison with the P2 conditions, or the actual conditions that will be used to view the images, to get an overall view of tone reproduction.

P2 Practical appraisal of PRINTS
This is recommended when one wants to make a judgment on individual prints. This viewing condition is not recommended for comparing prints against one another, with the exception of comparing a print with its image shown on a monitor. The lower illumination level of P2 makes this task easier. You should be aware that such a comparison, monitor vs print, should only be performed when the monitor and print viewing light have the SAME white point, usually D65 or D50. The illumination level is 500 lux at print level."

In practice the main difference you will notice is that you can see more shadow detail at the higher luminance viewing level.

The standard specifies that the screen luminance of your monitor should be between 75 and 100 cd/m2. Some calibration software calls up 120cd/m2 for laptops. Personally we like 75cd/m2 - apart from anything else it extends the life of the monitor! This rather low value should be compared with the figures that are bandied about for iPads, Macbook Pros and some low-end monitors of up to 400cd/m2. This is the most common finding for those who suffer prints that are dark compared with their screens - they are working at the default luminance. The prime requirement for a screen calibrator and its software is that you can choose and regulate the screen luminance AND check it afterwards! Often luminance settings are under 'advanced' buttons or 'pro mode'. The current rash of Retina screens have only served to make matters worse - they are never going to look like a print!


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1st Published 10/04/2015
last update 25/03/2020 12:33:24

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Updated 25/03/2020 12:33:24 Last Modified: Wednesday, 25 March 2020