In this assignment, we were asked to create two optimized images. STEP8A.JPG was optimized using the Photoshop Save As... function and STEP8B.JPG was optimized using the Photoshop Save for Web & Devices function. I would use the image on the right for a Web presentation and not use the left image as its file size is too large (44.2 KB). Both were saved as sRGB JPEG files:

STEP8A.JPG -- 24 dpi, Bit Depth: 32, Baseline ("Standard"), Quality: 6
STEP8B.JPG -- 96 dpi, Bit Depth: 24, Quality: 50 (Medium), Blur: 0

In this lesson, I learnt that as file size increases, so does the optimal download time. I learnt that it is important to pay attention to the size of a file and that examining an image's size under properties (i.e. the bracketed figure) is more accurate than relying upon the 56.6K figure displayed in Photoshop. As discussed in the PDF file for Assign-
ment 1, "To check the real file size of an image, on a PC right-click on the image file icon and select Properties." Using Save for Web & Devices, the download is reduced to 1 second from a download time of 6 seconds. This is because the browser has to process less image data. The image sizes are the same (202px x 162px), but the optimization used is not; the 8.15KB file results in a lower download time. Color used in each image is optimized differently; a larger color palette in the 1st image results in a larger file size, and therefore a larger download time. The image on the right, however, is restricted to fewer colors. The image to the left is more vibrant, but it also takes longer to download. The image on the right is better optimized for the Web.

In units 1-8, and in this assignment, we learned that preparing images for the Web doesn't start with saving. The image mode (i.e. CMYB or sRGB) must be correctly selected so that the image is properly formatted for what it is to be used for; traditionally, CMYB is used for print and sRGB is used for the Web. The pixel interpolation used in the Save For Web dialog is bicubic. This method produces an anti-aliasing effect which eliminates harsh pixilated edges. In creating images for the Web, there is a trade-off between quality and file size -- and as a file gets bigger, so does its download time. People who view webpages, don't want to wait too long. A download time of 6 seconds (i.e. use of the first image) is unacceptable, and the 1 second download time for the 2nd file is better suited to Web presentations, like the one shown here.