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60 essential skills: photoshop CS essential skills >>>>>> PHOTOSHOP CS >>> Step 7 – Sharpen Sharpnening the image is the last step of the editing process. Many images benefi t from some sharpening even if they were photographed and scanned with sharp focus. The ‘Unsharp Mask’ fi lter is used to sharpen the edges and corrects any blurring introduced during the digital process. The Unsharp Mask increases sharpness by emphasizing the edges where different tones meet. The Unsharp Mask works by increasing the contrast at the edges. The pixels along the edge on the lighter side are made lighter and the pixels along the edge on the darker side are made darker. Before you use the Unsharp Mask go to ‘View > Actual Pixels’ to adjust the screen view to 100%. To access the Unsharp Mask go to ‘Filter > Sharpen > Unsharp Mask’. Start with an average setting of 100% for ‘Amount’, a 1 pixel ‘Radius’ and a ‘Threshold’ of 3. The effects of the Unsharp Mask fi lter are more noticeable on-screen than in print. For fi nal evaluation always check the fi nal print and adjust if necessary by returning to the saved version from the previous stage. The three sliders control: Amount – this controls how much darker or lighter the pixels are adjusted. Eighty to 180% is normal. Radius – controls the width of the adjustment occurring at the edges. There is usually no need to exceed 1 pixel if the image is to be printed no larger than A4/US letter. A rule of thumb is to divide the image resolution by 200 to determine the radius amount, e.g. 200ppi ÷ 200 = 1.00. Threshold – controls where the effect takes place. A zero threshold affects all pixels whereas a high threshold affects only edges with a high tonal difference. The threshold is usually kept very low (0 to 2) for images from digital cameras and medium or large format fi lm. The threshold is usually set at 3 for images from 35mm. Threshold is increased to avoid accentuating noise, especially in skin tones. 61 capture and enhance essential skills >>>>>> PHOTOSHOP CS >>> Save Step 8 – Save, duplicate, resize and save again Go to the ‘File’ menu and select ‘Save As’. Name the fi le, select ‘TIFF’ or ‘Photoshop’ as the fi le format and the destination ‘Where’ the fi le is being saved. Check the ‘Embed Color Profi le’ box and click ‘Save’ Important > Always keep a back-up of your work on a remote storage device if possible. Duplicate your fi le by going to ‘Image > Duplicate Image’ command. Rename the fi le and select OK. Go to ‘Image > Image Size’. Check the ‘Constrain Proportions’ and ‘Resample Image’ boxes. Type in 600 pixels in the ‘Height’ box. Anything larger may not fully display in the browser window of a monitor set to 1024 × 768 pixels without the viewer having to use the scroll or navigation bars. An alternative to using this image resizing approach is to use the Crop tool. Typing in the dimensions 400px and 600px, dragging the crop marquee over the image and then committing the crop will also resize the image quickly and effectively. Note > Internet browsers do not respect the resolution and document size assigned to the image by image editing software – image size is dictated by the resolution of the individual viewer’s monitor. Two images that have the same pixel dimensions but different resolutions will appear the same size when displayed in a web browser. A typical image resolution that is suitable for viewing on a monitor is often stated as being 72ppi but actual monitor resolutions vary enormously. File format Destination Profi le 62 essential skills: photoshop CS essential skills >>>>>> PHOTOSHOP CS >>> JPEG format Set the image size on screen to 100% (this is the size of the image as it will appear in a web browser on a monitor of the same resolution). Go to ‘File’ menu and select ‘Save As’. Select JPEG from the Format menu. Label the fi le with a short name with no gaps or punctuation marks (use an underscore if you have to separate two words) and fi nally ensure the fi le carries the extension .jpg (e.g. portrait_one.jpg). Click ‘OK’ and select a compression/quality setting from the ‘JPEG Options’ dialog box. With the Preview box checked you can check to see if there is excessive or minimal loss of quality at different compression/quality settings in the main image window. Choose a compression setting that will balance quality with fi le size (download time). Excessive compression leads to image artifacts, lowering the overall quality of the image. File preparation overview 1. Select an image with full detail. 2. Select appropriate ‘Color Settings’ in the image editing software. 3. Acquire the image from the capture device with suffi cient pixels for quality printing. 4. Adjust the tonality and color to ensure the histogram is optimized for quality output. 5. Remove any dust and scratches. 6. Apply the Unsharp Mask. 7. Save the image as a TIFF or Photoshop fi le. 8. Duplicate the fi le and resize for uploading to the web. 9. Save the fi le as a JPEG with a suitable compression/quality setting. 63 capture and enhance essential skills >>>>>> PHOTOSHOP CS >>> Capturing in RAW More and more medium to high end cameras are being released with the added feature of being able to capture and save your pictures in RAW format. Selecting the RAW format stops the camera from processing the color separated (primary) data from the sensor, and reducing the image’s bit depth and saves the picture in this unprocessed format. This means that the full description of what the camera ‘saw’ is saved in the image fi le and is available to you for use in the production of quality pictures. Many photographers call this type of fi le a ‘digital negative’. Sounds great, doesn’t it? All the quality of an information-rich image fi le to play with, but what is the catch? Well RAW fi les have to be processed before they can be used in a standard image editing application. To access the full power of these digital negatives you will need to employ a special dedicated RAW editor. Photoshop CS is the fi rst version of the program to have such an editor built into the program. Designed specifi cally to allow you to take the unprocessed RAW data directly from your camera’s sensor and convert it into a usable image fi le format, the Photoshop RAW editor also provides access to several image characteristics that would otherwise be locked into the fi le format. Variables such as color space, white balance mode, image sharpness and tonal compensation (contrast and brightness) can all be accessed, edited and enhanced as apart of the conversion process. Performing this type of editing on the full high-bit, RAW data provides a better and higher quality result than attempting these changes after the fi le has been processed and saved in a non-RAW format such as TIFF or JPEG. So what is in a RAW fi le? To help consolidate these ideas in your mind try thinking of a RAW fi le as having three distinct parts: Camera data, usually called the EXIF data. Including things such as camera model, shutter speed and aperture details, most of which cannot be changed. Image data which, though recorded by the camera, can be changed in a RAW editor and the settings chosen here directly affect how the picture will be processed. Changeable options include color mode, white balance, saturation, distribution of image tones and application of sharpness. The image itself. This is the data drawn directly from the sensor sites in your camera in a non interpolated form. For most RAW enabled cameras, this data is supplied with a 16-bit color depth providing substantially more colors and tones to play with when editing and enhancing than found in a standard 8-bit camera fi le. 64 essential skills: photoshop CS essential skills >>>>>> PHOTOSHOP CS >>> RAW processing in action When you open a RAW fi le into Photoshop CS you are presented with a RAW editing dialog containing a full color, interpolated preview of the sensor data. Using a variety of menu options, dialogs and image tools you will be able to interactively adjust image data factors such as tonal distribution and color saturation. Many of these changes can be made with familiar editing tools like levels and curves controls. The results of your editing can be reviewed immediately via the live preview image and associated histogram graphs. After these general image editing steps have taken place you can apply some enhancement changes such as fi ltering for sharpness using an Unsharp Mask tool, removing moiré effect and applying some smoothing. The fi nal phase of the process involves selecting the color space, color depth, pixel dimensions and image resolution with which the processed fi le will be saved. Clicking the OK button sets the program into action applying your changes to the RAW fi le, whilst at the same time interpolating the Bayer data to create a full color image and then opening the processed fi le into the full Photoshop workspace. 65 capture and enhance essential skills >>>>>> PHOTOSHOP CS >>> Sam Everton 66 essential skills: photoshop CS essential skills >>>>>> PHOTOSHOP CS >>> Paul Allister ~ Control the color accuracy between monitor preview and print. ~ Understand the technical processes and procedures involved with producing a digital print. ~ Print a color managed digital image using a desktop inkjet printer. ~ Create a strategy to compensate for visual differences between the monitor preview and print. digital printing essential skills Amber Williams 68 essential skills: photoshop CS essential skills >>>>>> PHOTOSHOP CS >>> Printing to an inkjet printer Creating high quality prints when printing to a desktop inkjet printer can be a mystifying, painful and costly experience. If you are using an inkjet printer you can really only hope to get close to the quality of traditional analog prints from a darkroom if you print on digital ‘photo paper’ using a ‘6-ink’ inkjet printer (it is, however, possible to achieve reasonable print quality using a ‘4-ink’ inkjet printer and ‘photo quality’ or ‘high-resolution’ paper). High quality photo paper/fi lm ensures that images appear sharp, with small ink dots and richly saturated colors. Ink dots from an inkjet printer are most noticeable in the highlights of an image. The addition of light cyan and light magenta inks to the normal 3-ink color cartridge ensures smooth photographic quality highlights. Epson 6-ink printers retail under the ‘Epson Stylus Photo’ name, whilst Canon’s 6-ink models are referred to as ‘bubble-jet’ printers. RBG to CMYK Color on a computer’s monitor is created by mixing red, green and blue (RGB) light whilst the refl ected light from cyan, magenta, yellow and black inks creates color on the printed page. A perfect match is therefore very diffi cult, as the range or ‘gamut’ of colors capable of being reproduced by each of the two display mediums is similar but different. The colors present in a digital image fi le have to be translated or converted to fi t the gamut or ‘color space’ of each output device or printer. Profi les The accuracy of color translation has been helped in recent years by the introduction of ‘ICC profi les’, e.g. ‘sRGB’ and ‘Adobe RGB (1998)’. These can be tagged onto an image by capture devices and some image editing programmes as a way of recording how the colors in the digital image fi le actually appear to a specifi c capture device or when displayed on a particular type of monitor. In order to ensure this new level of visual consistency across all users we must fi rst ensure that our monitor’s contrast, brightness and color are within an acceptable range. The process of standardizing the monitor’s display characteristics is called ‘monitor calibration’. 69 digital printing essential skills >>>>>> PHOTOSHOP CS >>> Monitor calibration and working color space Reset the ‘Target White Point’ (sometimes referred to as ‘Adjusted White Point’) of the monitor to D65 or 6500, which is equivalent to daylight (the same light you will use to view your prints), using ‘Adobe Gamma’ (from the ‘Control Panel/s’ in Windows and Mac OS9) or ‘Display Calibrator’ (from the ‘Utilities’ folder in Mac OSX). Note > See ‘The Digital Darkroom’ for extended information on this important subject. Select an appropriate color setting for the software To create an on-screen preview of the image that will be eventually output by your printer, it is important to select a ‘working space’ for Photoshop that is sympathetic to the range of colors that can be achieved by your inkjet printer using good quality ‘photo paper’. The most suitable working space currently available is called ‘Adobe RGB (1998)’. To implement this working space choose ‘Color Settings’ in Photoshop and set the workspace to ‘Adobe RGB (1998)’ from the RGB pull- down menu. In the ‘Color Management Policies’ section, select ‘Convert to Working RGB’ from the ‘RGB’ pull-down menu. [...]... intent Now click ‘Print’ 81 >>> essential skills >>> >>> PHOTOSHOP CS essential skills: photoshop CS Amber Williams 82 layers and channels Zara Ellis essential skills ~ ~ Learn the creative potential of layers, adjustment layers, channels and layer masks Develop skills and experience in the control and construction of digital montages >>> PHOTOSHOP CS essential skills: photoshop CS Introduction The... channel this mode is used for monochrome pictures >>> essential skills >>> The most used color modes (channel types) are RGB, CMYK, LAB and Grayscale Unless you are working in the publishing industry, or you want to use advanced image editing techniques, you should keep your picture in RGB mode 93 >>> essential skills >>> >>> PHOTOSHOP CS essential skills: photoshop CS Adjustment layers Adjustment layers... This is true when adding adjustment and fill layers to your image When selecting, copying and pasting image parts, Photoshop also creates a new layer for the copied portion of the picture >>> essential skills >>> >>> PHOTOSHOP CS layers and channels 85 >>> PHOTOSHOP CS essential skills: photoshop CS Layer options Layer opacity Blend mode Fill opacity Preserve transparency and lock pixels Adjustment... gray Concentrate on the extreme shadow and highlight values to gain an idea of how your printer handles these tones Add a desaturated midtone to detect a color cast 71 >>> essential skills >>> >>> PHOTOSHOP CS essential skills: photoshop CS Soft proofing Although the image that appears on your monitor has been standardized (after the calibration process and the implementation of the Adobe RGB working... printer software dialog box Select ‘No Color Management’ Proofing Use daylight to assess color accuracy of print Create a ‘preview master’ adjustment layer if required 77 >>> essential skills >>> >>> PHOTOSHOP CS essential skills: photoshop CS Printing using a professional laboratory Professional photographic laboratory services are now expanding into the production of large and very large prints using... provided and then clicking OK 89 >>> PHOTOSHOP CS essential skills: photoshop CS Quick Masks, Selections and alpha channels When first starting to use Photoshop it is easy to think of Selections, Masks and Channels as all being completely separate program features, but in the reality of day-to-day image enhancement each of these tools is inextricably linked As your skills develop most image-makers will... outlined with ‘marching ants’ when switching to Selection mode When you save a selection you create a grayscale alpha channel >>> essential skills >>> Switching between Mask and Selection modes 90 >>> essential skills >>> >>> PHOTOSHOP CS layers and channels Saving Selections Photoshop provides users with the option to save their carefully created selections using the Select > Save Selection option In... use the same color settings as the bureau This may mean that you need to manually input set values for CMYK or use a ICC profile downloaded from the company’s web site 79 >>> essential skills >>> >>> PHOTOSHOP CS essential skills: photoshop CS Printing monochromes To the eyes of experienced darkroom workers the difficulties of printing black and white photographs with a color printer are immediately apparent... layer mask of the adjustment layer and proceed to print Note > The test file on this page is available from the supporting web site 75 >>> PHOTOSHOP CS essential skills: photoshop CS Analysis of the test print Print the test file available on the web site using the Photoshop color management settings outlined in this chapter Note > Make sure the color management is switched off in the printer driver software... and color information and then copy and paste this selection to its own layer Switch off the visibility of the background layer and then proceed to select ‘Print Preview’ as before 73 >>> PHOTOSHOP CS essential skills: photoshop CS Printer settings When you click on ‘Print’ in ‘Print Preview’ the printer dialog box opens The ‘Automatic’ and ‘Custom’ settings will override Adobe’s color management The . the full Photoshop workspace. 65 capture and enhance essential skills >>>>>> PHOTOSHOP CS >>> Sam Everton 66 essential skills: photoshop CS essential skills >>>>>> PHOTOSHOP. monitor preview and print. digital printing essential skills Amber Williams 68 essential skills: photoshop CS essential skills >>>>>> PHOTOSHOP CS >>> Printing to an. 8-bit camera fi le. 64 essential skills: photoshop CS essential skills >>>>>> PHOTOSHOP CS >>> RAW processing in action When you open a RAW fi le into Photoshop CS you