Speaking of long download times, how many of you optimize your photos and images before you put them on your website? What’s optimization, you say? It’s the process of making the image as small in filesize as possible (smaller filesize = faster download) while still maintaining a certain level of clarity and crispness. This is usually done through compression, which almost any image editing software will do, if asked nicely.
Too many times, I have visited websites where the images are scanned in lifesize or photos are dumped directly from the digital camera to the web. Beginner web designers don’t realize the images are so large, because they seem to appear instantly when testing the website on their own machines. Well, of course they do – they’re already ‘downloaded’ to your hard drive! And to make matters worse, a lot of drag and drop website software will allow you to place an image on a web page without optimizing it. The image may ‘look’ small, but all you really did was ‘virtually’ resize it with web code (HTML), not actually resize it with proper compression and optimization.
The key here is to learn how to use your graphics software (PhotoShop, Paint Shop Pro, Fireworks, anything that edits images), apply the proper amount of compression and select the proper resolution.
JPG compression is as much art as science – there is no set value that works for all images. Play around with the compression settings, and look for the best combination of compression percentage (higher percentage means ‘less’ compression) and clarity – If you apply too much compression, the image will become very blocky or blurry.
As far as resolution, be sure to resample all images to 72 d.p.i. (dots per inch). Monitors cannot support anything higher anyway, so all that extra info is wasted space (and longer download times). By way of comparison, scanners usually scan at 300 dpi or higher. That’s OK, scan at the higher resolutions, just be sure to resample to 72 dpi when you’re ready to put that image on the web.
With careful planning, compression and resolution changes, you can achieve huge savings in file size (and subsequent bandwidth / transmission costs) for your website. Smaller sizes mean faster downloads, and faster downloads means a more responsive and customer-friendly website. That almost always turns into higher profits, as people stick around to see your info and don’t click away while they wait for an image that will never appear!