One of the joys of photography is being able share treasured images with family and friends. When I first started taking digital photographs, I emailed a lot of picture files, but then I realized that many people didn’t know how to open and view a picture file, and also that I was loading up people’s email boxes with really big files. My solution was to open an account at a web based picture hosting site. Now I just send folks a link to the pictures I want to share, and only make prints on request.

There are many hosting sites, such as Yahoo, MSN, BytePhoto, and PBase, to name a few. Some of them are free, while others charge a modest fee.
But even the web gallery approach can be a burden to our friends if we upload pictures that are large in pixel dimensions, which requires they scroll in order to see them, or large in file size, since they can take quite a while to download, particularly for those with dial-up internet connections. Note that these size considerations are equally applicable for pictures that you imbed in posts on the DPR forums.

The problem is, some of us are unaware of these issues, and others don't know how to fix them. It's actually a two part fix, involving pixel dimensions and image quality.

Here's a link to an image from my 3 megapixel Nikon CP995. You may not want to click on it though, because even after cropping, it's really huge. The dimensions are 1832 by 1384 pixels (2.5MP), and the file size is 1.2MB.

http://www.pbase.com/image/23877293

The first step in making it user-friendly would be to downsize it, so it can be seen without scrolling. That’s easy enough to do with any image editing program. If you’re using some version of Photoshop, just go to [image], click on [image size], and change the width to 640 pixels. That automatically changed the height to 480 pixels for my picture. It's large enough to see the detail, but can be viewed all at once without scrolling by anyone whose monitor is running at a resolution of 640X480 or greater, which is most everybody these days. Problem fixed, right?

No. Because if I save this picture and upload it to my web-gallery without changing anything else, it will be almost half a megabyte, which would still present a burden for dial-up users. Try it and see.

http://www.pbase.com/image/23877548

There's an easy solution, though. When you alter an image in Photoshop and try to save it, the program first asks you to name the file, and then asks you to specify [jpeg options]. It allows you to select the "quality" of the file by moving a slider to set a number ranging between 0 (lowest quality) and 12 (highest quality). At the bottom of that screen, it actually predicts the file size that will result from the degree of compression you choose.

Nobody wants to show a poor quality picture, but guess what? Quality is used in a different sense when it comes to image files. It refers to how much the file will be "compressed". A large quality number means little compression, and a small quality number means a lot of compression. Here's an example of my huge picture, downsized to 640X480, at several different "quality" levels. Let's see if you can spot a significant difference between them.

Compressed to level 10 (275KB)
http://www.pbase.com/image/23877294.jpg

Compressed to level 6 (155KB)
http://www.pbase.com/image/23877295.jpg

Compressed to level 4 (117KB)
http://www.pbase.com/image/23877296.jpg

Now I've got “senior” eyes, but for purposes of sharing a picture with friends on their computer screens, I don't see much difference at all.
My approach is to downsize pictures to 640 pixels in the largest direction, and then to select a level of quality/compression that will result in a file in the range of 100KB. That makes them easy to see, and quick to download. I hope you'll consider doing the same; it’s good Netiquette.

Happy shooting!

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Warm regards,
Uncle Frank, FCAS Charter Member,
Hummingbird Hunter, DPR/NTF Supporter
Coolpix fifty seven hundred and nine ninety five
http://www.pbase.com/unclefrank/coolpix&page=all