How to... Edit Photos (Pt.1)

First Steps

One of the most important factors to creating a faster and leaner web site is the size of image.

If you have several large photographs to include on your Web page, the simple answer is — don’t! Instead, consider placing ‘thumbnails’ (tiny images created by reducing the original photo) on the page, with external links to the larger images.

Even so, the large image the thumbnails link to should not be higher than 640x480.

Follow these short Irfanview tutorials to enable quick and easy editing of the photo to the size you require. Oh, and while we're at it, this will help you to brighten, sharpen, saturate and save the photo too (see part 2)!

If you cannot understand any point, please mail me.

The first action is to run the IrfanView program and then load up the image.

• Press 'O' to open the File Selector.
• Locate the image file you wish to edit.
• Click on the file and press 'Open'.

Cropping

To make best use of the object, removing all the excess space is often advisable.

To do this first create a frame (often called a 'marquee') around the portion you wish to retain:

• Click and hold down the left mouse button on any corner of the frame you wish to make.
• While holding the left mouse button down, drag the mouse to create the desired frame around the object.
• Press 'Ctrl-Y' to crop the image.

Rotating

Sometimes, the image will look far better when created as a 'Portrait' – tall, narrow items like vases are obvious examples.

These are taken with the camera turned through 90 degrees, but when you view the photo it's on it's side:

• Either press 'L' or 'R' to turn the image left or right respectively.

Alternatively you can turn the image through any angle. To do this press 'Ctrl-U' to open up a dialogue box.

• Enter a figure into the 'Angle:' field. A negative figure will turn the image anti-clockwise.
• Press 'OK' button.

Resize: get out the thumbscrews...

Sounding like terms used in medieval torture, thumbnails, crunchers and splicers are all tools that can make a massive difference to your site.

But if your budget is limited, IrfanView will create a small thumbnail:

1. Press 'Ctrl-R' to call up the dialogue.
2. Ensure the 'Set new size:' button is selected.
3. Enter '150' into either the 'Width' or 'Height' field — whichever is the largest dimension.
4. Ensure the 'Preserve aspect ratio' box is ticked.
5. Enter '72' into the 'DPI:' field.
6. Click the 'Resample' (better quality) button.
7. Choose the slowest (Lanczos filter) method from the 'Resample filter:' field.
8. Press the 'OK' button to start the process.

On each occasion, save the new file using a different file name;
e.g. newfile.jpg and newfile-t.jpg

Sharpening

Sharpening is often necessary following a Resize operation.

A softening of the edges occurs that can make the image look indistinct and sharpening can make a small, but very noticeable difference to the quality of the image:

• Press Ctrl-E and click 'Sharpen'.
• Enter a value of about 10, although a little experimentation might be necessary.
• Press 'OK'.

A very subtle change, but the image should now look much cleaner and crisper.

Saving

You can now save the image if you're pleased with the result, or go to page 2 for some image processing tutorials.

To save the image:

• Press 'S'
• Locate the directory where you wish to save the image. Normally the 'My Images' folder is used, which is within the 'My Documents' folder.
• Enter the name for your file into the 'File name:' field. Do not use spaces!
• In the dialogue on the right, make sure the 'Save as progressive JPG'
• Move the 'Save quality:' slider so that the figure reads between '70' and '75'.
• Click the 'Save' button.

About JPEG Images

It must be noted that JPEG (pronounced "jay-peg") images use a compression method where a certain amount of the picture data is lost (called "lossy"). This method is important as it permits very small image file sizes.

Providing you don't overdo the compression, a visitor to the web site should never notice the difference. However, repeatedly saving and editing the same photo compounds the data loss making it degrade rapidly. It is therefore very important to always retain the original photo and never overwrite it.