Making fixed sized selections in Photoshop

When you need a series of same sized images, you can create an image using a fixed size selection in Photoshop. To do this, choose the Rectangular Marquee tool and selecting the Fixed Size option from the Style dropdown list. Set the width and height in pixels and then click on the image. A marquee of this size appears and you can drag it with your mouse to position it in the correct place and then crop the image. If you simply want to select with the same overall aspect ratio but resize the image later on, select the Fixed Aspect Ratio option and set the ratio of height to width for the selection.

If your selection is not a regular one, for example if you want to cut a piece from a series of images in the shape of Australian, make the selection and save it to a channel in the document by choosing Select, Save Selection. With the document still open, open the images to crop the shape from and load the selection using Select, Load Selection and select the image in which you saved the selection from the dropdown list. Now you can move the selection into position and crop the shape from the image.

Create a winning smile in GIMP

Shiny white teeth look great but, let's face it, not all of us have the benefit of expensive orthodontics. Luckily, armed with some graphics software you can give yourself or your best friend a professional whitening job in seconds.

To whiten teeth, in GIMP, click your favourite selection tool and make a selection around the teeth. Take care to select all the tooth area but avoid including any of the gum line or lips. You may find the "Select contiguous regions tool" is the best to use. Set a feather by choosing Select, Feather and set a feather value of 1 or 2 if the image is large.

Choose Tools, Color Tools, Hue-Saturation and click the option button for the Yellows so you'll adjust only the yellow coloring in the selected area. Reduce the intensity of the yellow by dragging the Saturation slider a little to the left. Check the Green and Red channels to see if altering their saturation has an effect and repeat as needed. Click on the Master button and drag the Lightness slider to the right to lighten the entire selection.