Image editing is the heart of the creative act of photographic printmaking-- it is where you transform a well-crafted snapshot into a work of art. It is where you implement Ansel Adams' oft-repeated statement,
"The negative is comparable to the composer's score and the print to its performance."In his youth Adams was disappointed by camera shop prints of his mountain photographs-- they didn't convey what he saw and felt. That disappointment launched him on a successful quest to make prints that conveyed his feelings about the landscape he loved. He shared his knowledge in his Basic Photo series, particularly in The Negative and The Print, classics that are relevant to this day. Technology has transformed the means of image editing, but not the ends.
Adams realized that a print can never capture the tonal range of an actual scene, particularly a naturally illuminated landscape. A print has a maximum tonal range of no more than 100:1. Scenes have widely varying tonal ranges, often much greater. If you try to transfer a scene literally to a print, the contrast may be too low, resulting in a flat appearance. More often it's too high, blocking out highlights and shadows. Even if you correct the contrast (and do nothing else), you will rarely capture the visual experience of the scene.
Why? Because our eyes function differently when viewing prints and viewing scenes. As they move about a scene, they constantly adapt to differences in illumination using all sorts of cues not present in a print. The scene we experience is the result of numerous small and large adaptations. When we look at a print, our eyes hardly adapt. They grasp the print as a whole. In order to capture the feeling of a scene, those adaptations have to be put into the print. And to capture the artistic essence of the scene-- to reveal its essence-- we often have to go a great deal further.
In practice, this means if you photograph in natural light, you must dodge (lighten selected areas of a print) and burn (darken selected areas). When I started with photography I thought the master straight photographers (Alfred Steiglitz, Paul Strand, Edward Weston, Wynn Bullock, and Ansel Adams, to name a few.) who practiced "pure" photography didn't do much dodging and burning. Wrong! They were consummate artists who understood the workings of the human eye. They worked very hard on their prints, balancing every element to maximize the visual intensity. They would have loved digital technology. As Paul Caponigro said in a 1973 workshop,
"If I were God, I would say 'Let there be light.' Then I'd never have to dodge or burn."Some of the specific goals of image editing are
- Adjust the geometry: crop, rotate, correct perspective distortion, etc.
- Remove dust specks and scratches.
- Correct for lens aberrations, if needed: distortion (barrel and pincushion), chromatic aberration (color fringing), and light falloff (in wide angle lenses).
- Adjust the brightness, contrast, color tint, and color saturation of the image as a whole.
- Adjust portions of the image to bring them into balance with the image as a whole. This typically involves the use of masks and may be facilitated by sophisticated techniques such as contrast masking.
- Sharpen the image, and, if necessary, reduce grain.
Picture Window Pro from Digital Light and Color
Digital Light & Color was founded in 1993 by Jonathan Sachs, co-founder of the Lotus Development Corporation and author of Lotus 1-2-3, one of the landmark programs of personal computing. When Jonathan left Lotus in 1990, he combined his formidable software skills with his passion for photography to create a digital photo editing program that has evolved into today's Picture Window Pro. Picture Window Pro is an extremely powerful image editor that has every feature serious photographers require. Among them,
- Full support for ICC color management.
- Full support for 48-bit color and 16-bit B&W files. This allows repetitive edits with no loss of quality.
- Outstanding masking capabilities for adjusting portions of an image, including creating masks based on image properties.
- A wide array of geometrical transformations, including resizing, cropping, rotation, warping, perspective correction (equivalent to lens tilt), lens distortion (barrel and pincushion) correction, and lateral chromatic aberration (color fringing) correction.
- Excellent tutorials and support. See the message board.
The inevitable question will arise, "Why not Photoshop?" Photoshop is, after all, the dominant image editor in graphic arts. The answer: Picture Window Pro is less expensive, easier to learn and easier to use. And extremely powerful. Photoshop is intended for advertising and display. It has an enormous range of features most photographers will never need; features which make it difficult to learn and less than intuitive to use. As a result, a whole industry has grown up around teaching it; numerous classes are offered and over 400 books are in print. You can start making artistic prints of the highest quality far more quickly with Picture Window Pro. And if needs be, you can always open the files with Photoshop. I often talk to people who have tried digital printing but prefer the old-fashioned chemical darkroom. They have one thing in common: they've struggled with Photoshop.
Robert Schwiebert's eloquent comments sum it up.
I've been a Photoshop user for a few years and have accumulated a number of good plug-ins and actions to support my photographic workflow. In the past I had glanced a PWP, but didn't really take anything seriously except Photoshop. Then I spent some time reading your various articles that reference PWP's use, and I decided to download a demo copy to work with. After spending some quality time using the program I realized that, for photographic work, it provides all the capabilities of Photoshop plus my add-ons, and much more. It's hard to know where to stop in singing its praises: a clean and consistent user interface, fast image processing, exceptional documentation, 48 bit image support, lower cost upgrade path, ... I can really see why you promote it so much, and I hope it gets a more prominent place in the market. Anyway, the upshot is that I've officially retired Photoshop. It's very satisfying to have one high-quality, well-integrated tool that serves my photographic needs.
The Picture Window screen
The title bar (top row) contains the program name and version and the usual Windows boxes for minimize, maximize and close. The second row contains pull-down menus: File, Edit, Transformation, Mask, Tools, Window and Help. Commands accessable through this row are summarized in the table below. The third row contains icons for selected operations. The workspace is everything below the third row. Only a portion is illustrated. It contains images and dialog boxes. The Levels and Color transformation, described below, is in progress. |
Images are edited by means of transformations, which operate on the entire image or portions selected by a mask, and by tools, which typically operate on small areas of the image, selected by dragging the mouse. Transformations create a new copy of the image; tools update the current copy.
A quick guide to Picture Window Pro functions, below, summarizes transformations, tools, and other operations.
Commands by operation, at the bottom, lists transformations by function (Color Balance, Contrast, History, etc.).
Image size and display
The true size of a digital image is its pixel size, for example 5,749 x 3,740 pixels. You can see image size by right-clicking on the image and selecting Display info, or clicking on Window, Info... Digital images are also specified by their size in inches and Resolution in dpi (dots or pixels per inch). For example, the box on the left indicates 1.44 x 0.93 inches at 4000.00 dpi resolution. Don't be overly concerned by these numbers. They refer to film in the scanner, and have no effect on the monitor display or print size. Picture Window ignores them (you set the print size when you make the print), but some programs use them for setting print size. If you need, you can change them without changing the image pixels using the Resize transformation with Preserve:File size and proportions. Most of the time I ignore them. When an image is opened, it is displayed at 1:1 magnification (one image pixel per screen pixel) if it's small enough to fit inside the screen; otherwise it is reduced to fit the screen. The amount of reduction, for example (1:8), is indicated at the top of the image window. Right-clicking on an image brings up zoom controls, several of which have icons: Zoom Out to Fit Screen , Zoom In and Resize (Expand Window), Zoom In , Zoom Out , Zoom to 1:1, Zoom to 1:1 and Resize. Use 1:1, or zoom in even more, when you need to examine examine imge pixels closely, for example, when you use the clone tool to remove dust specks or when you sharpen the image. Note that there are two options for zooming to 1:1. Zoom to 1:1 and Resize usually enlarges the window to fill the screen. I often use Zoom to 1:1 (no Resize), which has no icon, because it leaves the window unchanged, keeping tools and other windows uncovered. Thumbnail Browser. Clicking on the Browse... icon opens a Thumbnail Browser on the left of the Picture Window screen, shown here on the right. Click on the Browse button to select the folder to browse. OPT allows you to select Tiny, Small, Medium, or Large images. Small is shown; I normally use Large. Thumbnails can be sorted by name, date, or size. The thumbnail display can be used for managing image folders: you can open or delete files as you please. The Browser window can be resized (widened) to display thumbnails side-by-side. Thumbnails are stored in a file named PW35.BrowseInfo (similar in function to Windows XP's Thumbs.db), which is updated when the Thumbnail Browser is opened or the folder is changed. Warning: Deleting a thumbnail deletes the image file itself. Be careful! |
Image editing sequence
Image editing is typically performed in the following sequence. Each step involves a tool or transformation. The sequence is, of course, not rigid. I tend to follow it most of the time, but there always afterthoughts-- I'm forever finding dust specks I missed, especially after sharpening. Then there's that last tonal adjustment... Before you start, make sure your system is calibrated so your monitor conforms to generally accepted standards (gamma = 2.2 for Windows, etc.) and your prints match your monitor. - Crop the image and make any other geometrical adjustments using transformations in the Geometry toolbox.
- Clean up the image-- remove scratches and dust spots using the Clone or Speck Removal tools.
- Adjust the overall brightness, contrast and color. A huge arsenal of transformations is available for this purpose: Filter and the Gray and Color toolboxes.
- Create masks if needed and adjust portions of the image.
When tonal and color adjustments are complete, sharpen the image with Unsharp Mask. Use a mask to avoid sharpening smooth areas like skies-- sharpening increases grain. If grain is objectionable, consider using a separate program, Neat Image, to reduce it. It comes close to working miracles.
- Select the image to be adjusted (click on it).
- Select the transformation. This brings up a dialog box with sliders and other controls.
- To adjust a portion of the image, select a mask by clicking on the box to the right of the Amount: slider and selecting a mask image. The Amount: slider splits into two sliders. White (the masked area) defaults to 100% and black (the unmasked area) defaults to 0. You may need to adjust them appropriately.
- Make adjustments in the transformation dialog box until the Preview image looks good. The original and Preview images may be resized if necessary. With transformations that affect fine detail, such as Sharpen or Blur, I usually enlarge the Preview, and often the input image, to 1:1. I may move the amount slider from 100% to 0 and back to observe the effect of the transformation.
- Click OK to complete the transformation and close the dialog box. Click Apply to complete the transformation, keeping the dialog box open-- useful for continuing where you left off.
- The new image is named Untitled n, where n is an integer that increments in steps of 2 (1, 3, 5, ...). After several transformations, Untitled images can crowd the screen and gobble memory: 48-bit images scanned at 4000 dpi from 35mm film can be as large as 120 MB. You can access a chart with the history of these images (the transformation that created each of them) by clicking on the Windows tab in the Thumbnail Browser. You should name and save "keepers" and delete intermediate images you no longer need. It's a good idea to save an early, good version of an image, before you do too much processing. I usually save a version after I've cropped it, removed dust, and done some basic color adjustment, but before I've adjusted masked areas or done any sharpening, just in case I misjudge something along the way.
Transformation example: Levels and Color...
The Levels and Color transformation makes a good example. It's the Swiss army knife of transformations for adjusting color, brightness, and contrast: easy to use and versatile, though not as powerful as specialized transformations such as Brightness Curve (B&W) or Color Curves (color), which are my favorites. The Preview, Apply, OK and Cancel boxes appear in most transformations. Preview is grayed out when Auto is checked. Apply performs the transformation (creates a full image), but leaves the dialog box open for further adjustments. OK performs the transformation and closes the dialog box. Full Range is specific to Levels and Color. It sets Dynamic Range (the black and white pointers) so the so the minimum is 0% and the maximum is 100%. OPT allows you to set options, which may be specific to the transformation. The options in Levels and Color are generic: Reset and Probe Size.
Most transformations have an Amount slider to control the amount of the transformation. When no mask has been selected (the box to the right of Amount is pure white), there is a single Amount slider. To select a mask (a B&W image the same pixel size as the Input Image, used to select areas that receive adjustment), click on the box on the right of the slider. Available masks (loaded in PW Pro) can be selected, and a double slider appears, as shown on the right. The double slider allows you to control Amount separately in dark and light areas of the mask (gray is intermediate). The default is 100% adjustment in white areas and 0% in black, but it can be inverted or set as desired.
The adjustments below Amount are specific to Levels and Color. The Midtones slider and the black and white pointers below Dynamic Range control the midtones, shadows, and highlights, respectively. These controls allow you to adjust both brightness and contrast. Clicking the Full Range box on top sets the left (black) arrow to 0% and the right (white) arrow to 100%. I use Brightness Curve (B&W) or Color Curves when I want to perform these adjustments more precely, with a histogram display. Sometimes when Color Balance is used, you may want to increase the right (white) arrow beyone 100%. Clicking the Invert clipped pixels in preview box shows when you've gone too far.
Clicking on the Color Balance box brings up a color picker window, illustrated in the lower right. The Color Picker offers a number of options, including selecting colors by typing numbers in boxes or using standard filters (CC or Wratten designations). The Color Balance box affects mostly highlights. The Color Balance transformation has six boxes for adding or removing color casts from highlights, midtones, and shadows.
Color Space: can be set to HSV or HSL. These two spaces, which transform RGB images into hue, saturation, and lightness or value, are required for adjusting tones. (Lightening or darkening an RGB image presents the problem of how much to adjust each setting to keep the same hue.) You should be familiar with the effect of Color Space on saturation when you lighten or darken an image: HSV and HSL behave quite differently.
Last but not least is the Saturation slider. More options (Preserve Low, High, Low and High, and neither) are available in the Saturation transformation.
A quick guide to Picture Window Pro functions
This table shows highlights of available commands. I've omitted several; the entire list would be overwhelming. You may want to use the table as a reference and skip to the example below, illustrating the use of the versatile Levels and Color Transformation. I do most of my tonal and color adjustments with Brightness Curve (for B&W) and Color Curves (for color).
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Edit |
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Transformation Adjust the |
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Mask |
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Tools |
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Window |
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Help |
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Commands by operation
Commands are listed alphabetically by operation (i.e., function name) (in blue) for operations that are frequently required, not obvious, or can be accomplished by several transformations.
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Next steps
This page introduced Picture Window Pro and outlined its capabilities. To review the basics of image editing, read Making fine prints Part 3: Image editing or the online tutorials, The Basics of Digital Images, the Tutorial chapter from the Picture Window electronic manual, and Nine Tips for Making Better Prints. The key to serious image editing is selective adjustment with masks. Making masks quickly is a vital skill. To learn more, read Making masks or the online tutorials, Creating and using masksand Dodging and burning. For more depth, look at the advanced pages on image editing in Example: Sunset, Providence, Contrast masking (a very powerful technique for balancing contrasty images), and Tinting and hand coloring B&W images.
Images and text copyright © 2000-2009 by Norman Koren. Norman Koren lives in Boulder, Colorado, founded Imatest LLC in 2004, previously worked on magnetic recording technology. He has been involved with photography since 1964. |
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