Why not leave things as they are?
As cameras get more and more pixels, so image files get bigger and bigger. Canon's lowest pixel count is 5.0 Megapixels (Mp) on the PowerShot A460, and most of Canon's compact cameras are in the range 7.1 - 12.0 Mp

My latest cameras now produce images at 3888 x 2592 pixels, while my biggish monitor only displays 1680 x 1050 pixels. The images have nearly six times as many pixels as the monitor is capable of displaying.

This is true of the equipment most people have. A typical 1280 x 1024 pixel monitor is only capable of displaying 1.3 Mp - a far lower resolution than almost every digital camera still working. Cameras produce many more pixels than the monitor is capable of displaying. When you view full size images on your monitor the display software 'throws away' (temporarily at least) most of the image information.

Now you do need all those extra pixels for making high quality prints. So they are necessary. They just aren't needed when the images are viewed on a monitor.

So however you share your images with your friends - whether that be web site, Flickr, MySpace, or just as an e-mail attachment, they need to be no bigger than the biggest monitor they will be viewed on. The bigger they are the longer they take to transmit, and for e-mails - the longer they take to download into the Inbox.

Even in these days of broadband, many people still use dial-up modems at 56Kbits/sec or slower. At 56Kbps a 1MB file will take at least 3 minutes to download. My 10 Megapixel images even converted to jpeg can be anything between 3 and 5 Megabytes. Kept as uncompressed files they are about 30 Megabytes in size.

So it is a good idea to be able to resize your images if you wish to send them anywhere. Now Photoshop isn't the only way you can resize them, but it is software that many photographers have available in one or other of its incarnations; it is reliable; and it treats your images with respect.

The Seven Easy Steps to Resizing:

1. Open the image you want to resize
a. you can use File>Open or (Ctrl+O) or
b. you can use File>Browse or (Shft+Ctrl+O); click on the folder containing your image; then double-click on the thumbnail that you want to re-size.
2. go to Image>Image Size
3. a window will open with the pixel size of your image (Width & Height) shown at the top.
4. Ensure Constrain Proportions and Resample Image are both ticked.
5. Alter either the width or the height. The other will change in proportion.
6. Click OK
7. go to File>Save As or (Shft+Ctrl+S) and type a new name in the File name. Make sure you leave the file extension (the characters after the dot) as it is. If the file extension is NOT '.jpg' and you want to e-mail your image or upload it to a web site, then in Format: click the arrow and select JPEG. What this does is to create a new file, so that your original remains unaltered. It is a good idea to get into the habit of Saving As when you make any changes to an image. That way you if you make an unrecoverable mistake, you will always have your original to go back to.

What size should I choose?
If you want your images to be viewed filling the screen because they are so good then choose a number between 1000 and 1200 for the width. Otherwise a width of anything between 800 and 600 is useful rule of thumb.

Play around with different sizes until you get the effect, and the file size you want. And your friends will love you for not clogging up their e-mail with file attachments that take forever to download.

Re-sizing for Making Prints
If you are re-sizing your images for faster upload when ordering prints, these are roughly the file diemsnions you need to aim for in order to receive high-quality images from your photo print supplier.

These are the dimensions required for high resolution images. Uploading larger files will not increase the quality of your images, but uploading significantly smaller files will. For images that are viewed from a greater distance, e.g. for use on a wall, much lower image dimensions will still give acceptable prints.

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