The Digital Fine Print Course Notes 2012 Copyright Les Walkling 2012 Adobe Photoshop screen shots reprinted with permission from Adobe Systems Incorporated.
The Digital Fine Print Course CONTENTS Part 1: Creating a Fine Print • Printer Resolution • Image Resolution • Multi-Colour Printing 4 5 7 Part 2: Editing a Fine Print • • • • • • • Four Compositions: Image Editing Workflow Colour Correction Tools Converting Colour Images to Greyscale Understanding Unsharp Masking Advanced Unsharp Masking Image Posterization Reducing Noise and Artifacts 9 10 12 16 17 18 20 Part 3: Refining a Fine Print • • • • • • Print Luminosity Basic Layer Masks Blending Adjustmen
The Digital Fine Print Course Part 1 Creating a Fine Print Copyright Les Walkling 2012 3/50
The Digital Fine Print Course Creating a Fine Print Printer Resolution The standard units expressing digital image resolution, ppi (pixels per inch) and dpi (dots per inch), although often confused and interchanged, do not refer to the same attribute. • PPI (pixels per inch) is a measure of the digital file’s linear pixel resolution. The higher the ppi, the more pixels make up the image, and therefore the larger its overall file size.
The Digital Fine Print Course Creating a Fine Print Image Resolution The optimum pixel resolution of a print is dependent on the printing medium, the intended print viewing distance, and the required optical resolution. Printing Medium: The printing medium is a combination of the printing process and the paper used. A low resolution file printed on a glossy paper will look quite different when printed on a rough surfaced paper.
The Digital Fine Print Course Creating a Fine Print Image Resolution The following Bill Beath landscape image was re scanned at the same physical size but different pixel resolutions. Each image was then printed at the same size on the same paper with an Epson inkjet printer at the printer’s highest resolution of 2880 dpi.
The Digital Fine Print Course Creating a Fine Print Multi-Colour Printing Careful examination of CMYK and CcMmYK(k) prints reveal significant differences in the highlight regions. Highlight resolution is markedly improved when printed with a light cyan (c), light magenta (m) and light black (k), especially at the highest printer dpi, because compared with a ‘traditional’ CMYK inkset, more drops of the light ink will be deposited to produce the same highlight density which also preserves highlight detail.
The Digital Fine Print Course Part 2 Editing a Fine Print Copyright Les Walkling 2012 8/50
The Digital Fine Print Course Editing a Fine Print Four Compositions: Image Editing Workflow All images are composed of other images, both imagined and real. Identifying an image according its individual compositions and then exploring and refining their contribution, honestly reveals the structure of the image. By rendering the individual compositions in the following order, the image can be most efficiently resolved.
The Digital Fine Print Course Editing a Fine Print Colour Correction Tools To fully colour correct an image control is needed over six variables: 1. Hue 2. Saturation 3. Brightness 4. Density Range 5. Global Colour Balance 6. Local Colour Balance Photoshop’s Colour Picker displays a 2D representation of 3D colour space. Hue: The hue of a colour is what is often thought of as the actual colour or ‘colour of the colour’ and is described by its (hue) angle on a 360º colour wheel.
The Digital Fine Print Course Editing a Fine Print Density Range: Density range refers to the tonal or brightness range of the image and is not the same as its colour range (or balance). Mode changing a colour image to a greyscale image changes its colour values to density values. This represents the tonal darkness and lightness of the print. An image's tonal composition may be different to its colour composition.
The Digital Fine Print Course Editing a Fine Print Converting Colour Images to Greyscale There are at least five methods for converting RGB to Greyscale. They are not the same. • Photoshop>Image>Mode>Greyscale • Photoshop>Image>Adjustment>Desaturate • Photoshop>Image>Mode>Lab then discard the a* and b* channels before converting Photoshop>Image>Mode>Greyscale to preserve the Lightness channel.
The Digital Fine Print Course Editing a Fine Print Altered Luminosity The luminosity of an image is our perception of the relative lightness and darkness of its colours. Photoshop’s luminosity formula mixes 30% of the Red channel + 59% of the Green channel + 11% of the Blue channel to represent the luminosity of the image. In traditional BW photography contrast filters were used to alter this luminosity rendering. For example a red filter was used to dramatically darken blue sky and intensify clouds.
The Digital Fine Print Course Editing a Fine Print Advanced Greyscale Workflow There are three typical stages or adjustment layers in an advanced greyscale workflow: 1. Extraction of a monochrome luminosity rendering from the original colour image. 2. Global redistribution of the image’s tone and contrast. 3. Local redistribution of the image’s tone and contrast. The original image is converted to monochrome RGB with Photoshop’s Channel Mixer.
The Digital Fine Print Course Editing a Fine Print Colourizing Monochrome Images A monochrome RGB image can be colorized (toned) by many methods such as RGB Curves and/or Color Balance adjustments. A Color blended ‘toning layer’ modified via Layer Style options is one of the more eloquent, accurate and adaptable methods. Photoshop’s Color Picker can be used to accurately specify the required colour.
The Digital Fine Print Course Editing a Fine Print Understanding Unsharp Masking Sharpening (and blurring) effects are proportional to the degree of enlargement of the final print. For example sharpening that appears perfectly balanced on a 100 ppi screen will become excessive when enlarged in a 200 ppi Lambda print. Local effects are proportional to the distance (enlargement) over which they are projected.
The Digital Fine Print Course Editing a Fine Print Advanced Unsharp Masking Photoshop’s Unsharp Mask filter increases edge contrast and therefore apparent sharpness, which appears as light and dark outlines around boundaries in the image. The exact degree of sharpening (outlining) the image requires will need to be determined experimentally for each printer at the final print size according to these parameters: . Amount: The darkness and lightness of the outlines.
The Digital Fine Print Course Editing a Fine Print Image Posterization Practical experimentation alerts us to the fact that a minimum number of levels of tone are required to create the illusion of a smooth tonal scale from black to white on the screen and in the digital print. With less than 8-bits or 256 levels of tone per channel the individual levels or steps may become increasingly noticeable as distinct jumps or bands of tone.
The Digital Fine Print Course Editing a Fine Print Minimising Image Posterization Posterization can be minimised (and therefore the illusion of smooth photographic tone preserved) by working with files that contain more than 8-bits (2 8= 256 levels) of data per channel. As many printer drivers and RIPs only accept 8-bits of data per channel it is also logical to only convert the image down to 8-bits of data per channel just before printing.
The Digital Fine Print Course Editing a Fine Print Reducing Noise and Artifacts in Scanned Images A digital print from a scanned negative will often exhibit a more granular image structure compared with an RA4 optical-chemical photographic print enlarged directly from the same negative. These artifacts appear in proportion to the film’s density. It therefore tends to not be as significant a problem with scanned transparencies whose reversed densities effectively ‘hide’ these artifacts in the shadows.
The Digital Fine Print Course Part 3 Refining a Fine Print Copyright Les Walkling 2012 21/50
The Digital Fine Print Course Refining a Fine Print Print Luminosity A fine print is the fine transformation of subject that matters. Four thoughts on foundations. A print is more than the sum of its parts. However each of its parts must be treated as their own image. Each image needs to be rendered according to its own demands. A foundation print harmoniously reintroduces these images to each other. Four thoughts on subject that matters. If we can not name our sources that is not too bad a thing.
The Digital Fine Print Course Refining a Fine Print Basic Layer Masks Layer masks control the local distribution of the layer they mask. Layer masks can be used in compositing different images together. They can also be used in the local control of specific values within a single Layer. For example different areas of an image may require different renderings in order for the image as a whole to be properly resolved. These differences may include changes in density, contrast, colour (hue) and saturation.
The Digital Fine Print Course Refining a Fine Print Blending Adjustment Layers Many of ‘Photoshop > Image > Adjustments’ can be loaded as Adjustment Layers. This allows incremental adjustments to be made with a reduced risk of incremental posterization. When the image is then flattened, archived or printed, only one adjustment per adjustment layer is applied. Blending Adjustment Layers with different Blending Modes further refines this technique by helping to constrain the adjustments to desired values.
The Digital Fine Print Course Refining a Fine Print Working in L*a*b* One of the advantages of working in the CIE LAB colour space is that it separates the image into a Lightness channel (L*) and two colour channels (a* and b*). This encourages the editing of tone independently of colour. L*a*b* L* L*a* (magenta to green) L*b* (yellow to blue) L*a*b* is also a device independent and very large colour space.
The Digital Fine Print Course Refining a Fine Print Out of Gamut Colours Saturated colours such as the green paint of this car can be accurately captured on film or with a DSLR camera. Many of these colours can also be preserved in the Adobe RGB (1998) working colour space. However once printed they becomes dull and lifeless. Adobe RGB 1998 (Working Space Profile) U.S. Web Coated (SWOP) v2 (Press profile) Many of the colours in this image (35.4% ∆E2000 > 2.0) lie outside of the US Web Coated (SWOP) v2.
The Digital Fine Print Course Refining a Fine Print Editing Out of Gamut Colours Whenever the Perceptual gamut mapping intent in a destination profile fails to adequately separate out-of-gamut colours, then these colours will need to be manually edited into the destination gamut. One approach compresses the colour gamut (range of saturation) to bring the image into gamut and then expands the tonal contrast (range of tones) to compensate for the reduced colourfulness.
The Digital Fine Print Course Refining a Fine Print Lobster - Totally Independent Tone and Colour Correction On closer inspection via the Info Palette, Photoshop’s Luminosity and Color Blending Modes do not restrict editing changes solely to the luminosity or colour of the image. Even when points are ‘locked down’ on a Luminosity blended Photoshop RGB curve their colour is still modified when adjacent points are edited.
The Digital Fine Print Course Part 4 Printing a Fine Print Copyright Les Walkling 2012 29/50
The Digital Fine Print Course Printing a Fine Print Photoshop CS™ Printing with Custom RGB Printer Profiles Select PRINT WITH PREVIEW to layout the image and set the Color Management options. The image’s colour space (Embedded Profile) will be automatically detected and set as the SOURCE SPACE. Manually select your custom printer profile as the PRINT SPACE with Relative Colorimetric rendering intent and Black Point Compensation turned ON.
The Digital Fine Print Course Printing a Fine Print Photoshop CS2™ Printing with Custom RGB Printer Profiles Select PRINT WITH PREVIEW to layout the image and set the Color Management options. The image’s colour space (Embedded Profile) will be automatically detected and set as the DOCUMENT PROFILE. Manually select your custom printer profile as the PRINTER PROFILE with Relative Colorimetric Rendering Intent and Black Point Compensation turned ON.
The Digital Fine Print Course Photoshop CS3™ Printing with Custom RGB Printer Profiles: Select PRINT to layout the image and set the Color Management options. The image’s colour space (Embedded Profile) will be automatically detected and set as the DOCUMENT PROFILE. Select PHOTOSHOP MANAGES COLORS in the Color Handling options. Manually select your custom printer profile as the PRINTER PROFILE with Relative Colorimetric Rendering Intent and Black Point Compensation turned ON.
The Digital Fine Print Course Mac OS X: Epson Printer Driver Settings Select the correct Printer Driver Settings and save them as a PRESET for repeated use. The two required settings are PRINT SETTINGS and COLOR MANAGEMENT which should be set to the same conditions as was used to produce the printer profile.
The Digital Fine Print Course Printing a Fine Print Windows: Printer Properties Settings Clicking on Windows’ Print dialogue box Preferences button opens the Advanced printer Settings dialogue that need to be correctly selected and saved for each printer profile. The saved Custom Preferences ensure error free printing with that profile. 1 Select Preferences Set the correct printer settings as required by your printer profile.
The Digital Fine Print Course Printing a Fine Print Epson K1, K2 and K3 Inksets Epson’s Ultrachrome inksets are available in three generations, K1, K2 & K3. While they all exhibit the same archival stability, their other attributes differ substantially. Colour Gamut and Linearization: These 2D gamut projections indicate some of the characteristics of each inkset relative to the RA4 (Lambda/Kodak Endure E) photographic paper colour gamut. A 3D gamut comparison reveals even greater differences.
The Digital Fine Print Course Printing a Fine Print Understanding RIPs RIPS (Raster Image Processors), like printer drivers, are used to communicate with a printer. However RIPs tend to do this with more sophistication and control than printer drivers.
The Digital Fine Print Course Printing a Fine Print ImagePrint Fine Art RIP Image Print is quite unique among RIPs because it accepts RGB data and uses RGB printer profiles (like printer drivers) but without the restrictions of operating system level printer drivers, such as page length limitations. Files can be dragged into the image Print layout window and manually (or automatically) placed on the page or roll.
The Digital Fine Print Course Printing a Fine Print QuadTone B&W RIP The QuadTone RIP (www.quadtonerip.com) is also used with Epson K2/K3 Ultrachrome printers to provide advanced ink controls for superior B&W printing. It is a software solution, rather than a colour managed (profile based) solution, or an inkset solution. As the QuadTone RIP is not profile based, it doesn’t include a soft proofing function. This limits its effective contribution to an efficient and productive B&W printing workflow.
The Digital Fine Print Course Printing a Fine Print RIP Ink Limiting Traditional RIPs permit most printer functions to be customized and controlled by the user. However the user then has to take responsibility for setting up and maintaining the RIP. For example, setting up a Traditional RIP involves: 1. Creating a new 'setting' or 'environment' for the media being used because each media will require different settings for optimum (and economical) output. 2.
The Digital Fine Print Course Printing a Fine Print RIP Linearization 3. Once the media’s ink limits have been determined the next step is linearization. Linearization test charts are usually supplied with the RIP software, and should be available in different formats to suit different spectrophotometers. They usually comprise step wedges in cyan, magenta, yellow and black, and sometimes also combinations of CMY and CMYK.
The Digital Fine Print Course Printing a Fine Print RIP Profiling 4. Once the printer has been ink limited and linearized for the new media, and the new linearization settings have been saved in the media specific 'environment or preset' in the RIP software, the printer can then be 'profiled' by printing a CMYK profiling test chart. The resulting CMYK profile therefore describes that 'current state of the printer'.
The Digital Fine Print Course Printing a Fine Print Changing Epson Black Ink Cartridges in Mac OS X Th Epson Stylus Photo printer driver under the Mac OS X Printer Setup Utility is not updated when a Black ink cartridge is changed from Matte Black to Photo Black (and vise versa). The most obvious problem is that this does not reset the Epson driver, therefore the additional Photo Black Media Types, such as Premium Semigloss Photo Paper, are not available.
The Digital Fine Print Course Part 5 Viewing a Fine Print Copyright Les Walkling 2012 43/50
The Digital Fine Print Course Viewing a Fine Print Photoshop Soft Proofing with Custom Printer Profiles Final image adjustments prior to printing should be made while viewing the screen image ‘through’ your custom printer profile for the paper you intend to print on. 1. Go to Photoshop’s ‘View > Proof Setup > Custom’ settings and select ‘Custom’: NOTE: Softproofing will only be as accurate as your monitor profile. In all cases custom monitor profiles are highly recommended. 2.
The Digital Fine Print Course Viewing a Fine Print Soft Proofing Light Sources Soft proofing involves viewing, assessing and editing an image according to its appearance on a monitor that has been accurately calibrated to simulate the viewing conditions under which the finished print will be displayed. The practice of accurately soft proofing images is highly desirable because it can lead to increases in productivity, reliability and image quality. However it is a flawed concept.
The Digital Fine Print Course Viewing a Fine Print Solux Lamps Light sources such as SOLUX 12 volt 50 watt lamps are manufactured to the highest colour rendering specifications and are excellent for critically viewing photographic/inkjet prints. The SOLUX 4700ºK spectrum largely encompasses the spectrum of a standard monitor calibrated to 5000ºK. Therefore the monitor can be accurately calibrated to a SOLUX 4700ºK lamp, resulting in a larger gamut of colours being accurately soft proofed on the screen.
The Digital Fine Print Course Viewing a Fine Print Fluorescent Lamps There are a number of fluorescent lamps available that employ a large number (7+) of phosphers to create a smoother (less spiky or discontinuous) spectrum. Lamps manufactured by GretagMacbeth (http://www.gretagmacbeth.com) and GTI Graphic Technology (http://www.gtilite.com) are used in general room lighting installations as well as specially constructed viewing booths for the critical matching of colour samples.
The Digital Fine Print Course Viewing a Fine Print Soft Proofing Requirements For softproofing to be a dependable and useful procedure six criteria need to be satisfied. 1. The conditions under which the print will be displayed need to be known and precisely characterized. In terms of an exhibition venue, multiple measurements are averaged. 2. The monitor needs to be calibrated to a gamma curve that is very close to the gamma curve of the printer that the image will be printed on. 3.
The Digital Fine Print Course Viewing a Fine Print Ink Inconstancy Ink inconstancy is where the relationship between colours alters, sometimes drastically when a CMYK print is viewed under different lighting conditions. This is different to the overall colour shift that comes from moving the print from one light source to another. For example, as the wavelength of light moves from red to infrared our ability to see colour falls off gradually.
The Digital Fine Print Course References Bibliography DeWolfe, G. (2006), George DeWolfe's Digital Photography Fine Print Workshop, McGrawHill Osborne Media, USA Johnson, H. (2004), Mastering Digital Printing: The Photographer's and Artist's Guide to High-Quality Digital Output, 2nd edition, Muska & Lipman, USA Kieran, M.
