As a dial-up user, let me say how much I appreciate those of you who keep your image file sizes to a minimum (avatars, signatures, etc.). It's quite easy to use image editing software to decrease the file size without loosing much or any quality. This will save bandwidth, server storage space, and time for those of use still stuck in the slow lane.

This site will display avatars at 80 x 80 pixels. An image that is larger will download in its entirety, but the browser will have to resize it (simply losing some or most of the pixels) in order to fit it into the smaller box. I've seen avatars as big as 250K, which, if displayed at full size, would fill most of the screen. It is quite possible to have an 80 x 80 .jpg image, if some compression is used when saving, that will have a file size of about 2K.

Happy surfing, browsing, posting, skating, singing ... EEEEE!

See nymphadora's pinned thread, Guidelines On Image File Size, for useful info.

About resizing pictures ... You might want to resize a picture for one or both of these reasons: to make the pic physically smaller on the screen, and/or to make the file smaller so that it takes up less storage space, less bandwidth, and loads faster on web pages (particularly for dial-up users). Reducing the size of the picture will make the file smaller, and using compression on JPG files will make the file smaller still!

First, you need a photo editing program. Having an older computer, I don't know if this is commonly bundled with new computers. I would think the software you get with a digital camera would include photo editing software. The software I use came bundled with a scanner. The instructions below are what I do using iPhoto Express, though I believe you can accomplish the same thing in a similar way with other editing programs.

CHANGING THE SIZE OF THE PICTURE (number of pixels wide and high):
This is what I do using iPhoto Express: Open the picture in the program. Choose Photo / Resize. This opens the Resize dialogue box. Somewhere in there it tells you the current size of the photo, in pixels. There is a place to indicate a new size, either in pixels or inches; I always use pixels because it is more direct (the result when specifying inches depends on another setting -- pixels per inch -- too complicated). Then click OK. Save the newly resized image with a new file name so you still have the original image in the old file.

Also, in this dialogue box there is a setting for pixels per inch -- I usually ignore this. It has absolutely nothing to do with the size of the image on the screen or the printed page, though it can help you calculate image size for printing if you set it equal to the pixels per inch that your printer will use.

DETERMINING FILE COMPRESSION:
This refers to data compression and does not affect the size of the picture you see, only the size of the file. There is a tradeoff between compression and image quality, but very often you can dramatically reduce the file size with very little, even unnoticeable, loss in image quality. I'm usually dealing with .jpg files which, I believe, can be compressed using any photo editing program. Here's what I do using iPhoto Express...

Compression is selected when saving the file, so you would click File / Save, choose JPG as the file type, then click the Options button (you must choose file type before clicking Options or you won't see the correct options). This displays a dialogue box where you can choose a setting from 0 to 100, 0 being greatest compression (lowest picture quality) and 100 being least compression (highest picture quality). It doesn't seem that this number is a percentage, because choosing 80 will dramatically reduce the file size, and the reduction in quality is often unnoticeable. After choosing the compression number, provide a name for the file if needed, then click Save. I think that in order to see the result of the compression you have to close the file then re-open it.

Example: I took a picture with a 3 mega-pixel camera set at highest resolution (2048 x 1536) and least compression (Fine). The picture when displayed full size is much, much bigger than the computer screen, and the file uploaded to the computer is 1150K. After resizing the picture to 640 x 480 pixels and saving with least compression (100), it fits nicely on the screen, and the file is 244K. If this smaller picture is saved with compression setting at 80, the file is only 55K. And, it looks really good!

It's easier doing it than reading about it-- give it a try! Don't forget to save using a new file name so as to preserve the original file.

Peace.