Adobe Photoshop CS5 for Photographers - Martin Evening [308]
Save for Web & Devices
The ‘Save for Web & Devices’ option ( ) can be accessed via the File menu. This comprehensive dialog interface (Figure 14.8) gives you complete control over how images can be optimized for Web use, offering a choice of JPEG, GIF, PNG-8 or PNG-24 formats. The preview display options include: Original, Optimized, 2-up and 4-up views (Figure 14.8 shows the dialog window in 2-up mode display). With Save for Web & Devices you can preview the original version of the image plus up to three variations using different web format settings. In the annotation area below each preview, you can make comparative judgements as to which format and compression setting provides the best payoff between image quality and file size, and also determine how long it might take to download at a specific modem speed. Use the N-up Download speed menu (circled in purple in Figure 14.8) to select from a list of modem and Internet connections on which these download times are based.
Saving for devices
The saving for devices was first introduced in CS3 and allows you to preview how a Photoshop image looks when displayed on various types of devices such as mobile phones. The details aren't really so relevant to a book on photography, so they're not covered in this chapter.
Web browser previews
The Select Web Browser menu allows you to select which web browser to use when you preview a document that has been optimized for the Web, such as the example shown in Figure 14.9, where I was able to preview the Save for Web & Devices image using the Firefox web browser. You can use the Preview menu list to select a preview setting and simulate how the web output will display on either a Macintosh display, a Windows PC display or with Photoshop compensation. Although these days I reckon it is safe to assume that everything will be viewed on a monitor using the PC 2.2 gamma standard.
Figure 14.9 When you click on the browser preview button, it opens a temporary page like the one shown here. This allows you to preview the Save for Web processed image as it will appear on the final web page. This is especially useful for checking if the RGB editing space used is recognized differently by the browser. So if you are relying on embedded ICC profiles to regulate the color appearance on screen, you can check to see if the profile is indeed being recognized by the selected web browser program.
Optimize image settings
The Optimize image settings section has an option that allows you to apply Progressive JPEG formatting. Most browsers such as Firefox and Internet Explorer support this enhancement, whereby JPEGs can be made to download progressively interlaced, the way GIFs can. If you check the ‘Optimized’ checkbox this option can be used to apply more efficient compression, but again is not generally compatible with older web browser programs. The quality setting can be set as Low, Medium, High, Maximum or set more precisely as a value between 1 and 100%. The ‘Embed Color Profile’ option can be considered useful for those few browsers that do recognize profiles (such as Safari). However, many don't and the downside of including an ICC profile is that this simply adds to the overall web image file size, so I suggest you only use this option in special circumstances. The Blur control allows you to soften an over-sharpened original and obtain further file compression when using the JPEG format. You can also refine the amount of metadata that is saved with the Web output images. Limiting the amount of saved metadata can help keep the file size small.
Once you have configured these settings, you can go to the Options and settings menu (circled in