© Douglas Mesney 2011Like an 8-ball, black is something you want to be 'behind'.
Up front, black seems simple enough. There's even a song right...'Black is Black'? However, any printer can tell you that there's nothing simple about black.Black is the most elusive of tones.
What Is Black?
Black is defined by what is around it, as are all tones.
The white spot in the 8-ball above isn't white at all... it's a shade of gray that looks white against black.
© Douglas Mesney 2011Black is like people's behavior, part environment and part heredity. No matter the sources, you have to deal with what you've got. That is especially true in printing.
It's easy to identify a picture that has been printed with too much or too little black. But what is enough?
Dynamic Tone Range
Black is one of the two 'poles' of a histogram, white being the other. All other tones fall between those two absolutes. The range of tones between black and white is what I refer to as the Dynamic Tone Range. The word 'dynamic' is included in the term because a change to one tone has an effect on how all the others are perceived.
The number of tones in the range determines the look of the image. A representation of reality made with three colors cannot look the same as one made with thousands of different tones.
As tones are added, the dynamic tone rage widens... all the while anchored on black and white. That is why the black point and white point of a picture are so critical... and so problematic.
The problem begins with image capture and extends all the way through every step in the printing process. And what is the problem? Averaging.
Average Results
Virtually all image-processing algorithms are aimed at mid tones. Colors beyond their range are rounded up and averaged during processing. Only expensive capture devices capture details in the extremely dark and light regions of an image.
People use 'HDR' (High Dynamic Range) shooting techniques to extend the dynamic tone range. HDR is digital bracketing.
'Bracketing' is something photographers have been doing since George Eastman was in diapers. It's a fancy name for multiple exposures. You make a dark one, a light one, and middle one then mix together the best parts of each.
Now of course they make it seem that you need their latest gadget or software to do HDR... that's marketing. Read my book (and this blog) to find out how to do it the good old-fashioned way, without the expensive smoke and mirrors. But I digress...
Black and white is critical to the look of a picture, yet those two tones and those around them are the most problematic for printers.
Pictures are made on computers these days and people make them looking at monitors of all sorts. When a picture looks right on a monitor, it will make an OK print, but not a great one, as you already know, (maybe from reading this blog or my book).
Black and white on a monitor is not the same as black and white in printing. Not even by a stretch. So the files people give you to print will normally have problems in the dark and light tones, unless made by someone experienced in such matters of prepress, which is rarely the case.
Seeing In the Dark
© Douglas Mesney 2011Be a wise old owl, keep reading this blog.
'Luminosity' is being able to see details in the dark and light regions of the print. The quality of luminosity is the result of a very wide dynamic tone range.
Before very recently only real photographic prints had luminosity... and those fabulously expensive art lithographs and gravure prints. The reason? Those printing processes produced more tones than most other printing process... until now.
The very latest 10-color Epson® giclée printers produce the widest dynamic tone range of any printing process. That makes luminosity possible, but doesn't produce it automatically. Luminosity is something you add, by extending the dynamic tone range... a job called prepress.
'Prepress' is a term used to describe the adjustments to a picture file necessary to get the best results from a specific output device. Most of the work involves adjustments to the tone range. The prepress artist works up the tones in the dark and light regions, so that details can be seen better in these formerly 'hidden' regions.
How can you do prepress work on tones that you can't see on your monitor? Good question.
Fly by Wire
When you take a qualifying flight for an 'IFR' pilot's license (Instrument Flight Rating), the windows of the cockpit are covered. The pilot has to take off, fly and land the plane blind. Fortunately, you do not need to cover your monitor to control printing color.
Use the Eye-dropper sampling tool in combination with the Info Panel and the Color Picker to dial in your colors by number. At first it will seem awkward, but imagine how those pilots feel.
As you are sampling and reading the Info Panel, remember that in no case do you want 100% of anything or 0% (Zero) of anything.
That means stay away from Zero (black) and 255 (white) in the RGB section of the Info Panel.
In the CMYK section of the Info Panel, black limit numbers are:
- C 75%
- M 68%
- Y 67%
- K 90%
Notice in the Info Panel's CMYK numbers that 90% is the ink limit for black (K). Why? So dark tones don't clog up. (The white limit is Zero... no ink... the paper is the white tone.)
Strange looking numbers, eh? I told you blacks are weird.
Blacks Are Not Created Equal
Using all the colors on a four-color press makes 'rich black'. Black inks alone produce a wimpy dark gray tone, not black.
The numbers displayed in the Info Panel are arbitrary and simulate the ink blend for rich black on an average theoretical four-color press... of which none exists in actuality.
However, giclée-printing machines achieve black in a totally different way, as does your monitor. Nonetheless, the numbers are useful for identifying specific colors and when your shadow details are sinking into obscurity.
Every Color Has a Number
The millions of colors that your equipment can display and print each have a number, which is part of the information given in Color Picker. There you will also see the components of the color expressed as mixtures of both RGB and CMYK (LAB and CIE are spaces not usually used by print artists).
The significant thing about that color-numbering system is the control it offers. It means that you can address any of the millions of colors individually... you can change colors a millionth of a percent at a time. With that amount of control, there's no excuse for clogged up dark tones and burned out highlights.
Controlling Blacks
There are two types of control... technical and creative.
The artist who made the picture did the creative part, now it's your job as a printer to reproduce the artist's intentions as best you can. Of course, if you are the artist the following also applies...
Use the EyeDropper and Color Picker in combination with Info Panel readings to check what areas of the picture have slipped into the black void. If they are supposed to be black, that's one thing. However, if there are dark tones turning black in your prints, and you are losing shadow detail, you need to ease off the black ink levels in that region and develop 'highlights' in the dark (think night vision). How?
The answer(s) to that question are the subject of my book and of many blogs. However, to see what details are lurking in the shadow copy your picture onto another layer and then adjust the Brightness & Contrast to open up the darks and see inside.
If there are details in the shadows and you don't know how to get them in your prints, you need a copy of my book and/or a more thorough read through the contents in this blog.
This article will help you identify the black (and white) limits in the pictures you are printing, in terms of ink color instead of monitor color. The first step to getting out of the dark is identifying the problem. You can't see the light without it.
© Douglas Mesney 2004If you're a new reader, this blog was recently renamed. The first 70 articles are at http://gicleeprepress.blogspot.com and also at www.mesney.com.
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