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Making Selections 2

[Continued from previous page]

• Now that we have a mask, we can do some useful and interesting things. Click on the Palette icon to go back to painting mode, then click on the Mask icon on the toolbar; the Masking effect window will open.
• Notice how there's an unpleasant blue outline round the hands, caused by imperfect selection. When we come to paste it somewhere this will show up, especially if it's a contrasting colour. To fix this, click on the Grow icon; this adds a small amount to the edges of the mask. Most of the blue should disappear. If it doesn't, click again.
• Now click on Smooth. This blurs the edges slightly and gives a much better effect when you paste it somewhere; it ensures that edge pixels will 'blend' in colour with the destination. This process is sometimes known as "defringeing" or "dematting"; you can get a similar effect while you're actually making a selection by using the Feather option in the Copy window.
• Fix (Space) and save ... just in case.
• Now we'll try pasting it somewhere. Here's the destination image:

  

  Sunset over Chapel Allerton with Moon and plane [Fuji FinePix 2300, Feb 2002, scaled]

• Load this into Photodesk, alongside the hands. Make sure the hands image is currently active (click menu anywhere over the image), and ensure you're in Montage mode. Click on the Copy icon (two rectangles).
• Open the Copy window menu, and load your saved selection (Copy>Load from>#4 Alpha).
• Now just drag the hands (click and hold anywhere inside them) onto the sunset picture. An outline will follow the mouse, and when you release the Select button the image will appear (providing the Copy:Preview icon is on). If the hands aren't placed right, just drag them around. It's important to realise that this is only a preview; nothing has been drawn so far. The image will only be rendered when you fix it, either by pressing Space or clicking on the Tick.
• You should get something looking like this (scaled for the web):

  

  Trying it out

• There are several things wrong with this, which we'll now correct. Click on the Cross to get rid of the preview.
• First, the hands are too big. Go back to the hands image, and open its Channels window. Ensure that all the channels have their Pencil icon selected -- we want to do some operations on the whole image, and must ensure that the mask is affected as well. If the pencil is orange, it means that this channel can be written to (ie changed). It should look like this:

  

  Ensure the alpha channel can be written to

• Open the hands image's menu, and select Photodesk>Image>Resize... (or type Ctrl-S)
• Click on the Scale button, ensure Both axes and Bi-cubic interpolation are selected, and enter "2/3" into the By writeable icon:

  

  Resizing the hands

• Click on Resize and fix (Space) to confirm the change.
• What else is wrong? The light: the hands are illuminated from the left, but the light in the sunset picture is coming fron the right. Open the image menu, and select Photodesk>Image>X flip. Problem solved. This will also make a better composition, with the plane flying into the welcoming arms. Try it out (go into Montage mode and load the selection as described above):

  

  Scaled and flipped

• This still isn't quite right. The colours are wrong -- the hands are clearly reflecting bright blue sky, not sunset tones. Click on the Cross again, go back to the hands image and click on the Palette to return to painting mode.
• We want to add a slight colour tinge, so select the Paint pot and from the pull-down menu in the Palette window choose Filter.
• What colour to use? The best way to find out is to sample the sunset itself. Click on the Syringe at the right of the toolbar, and your pointer will also change to a syringe. We can now 'pick up' a colour from anywhere we like.
• It's best to choose an area and average the colours in it, so hold down the Alt key and drag out a small rectangle over a sunsetty-coloured bit of the photograph. If you just click on a single pixel it can be hit-and-miss whether you get the colour you want.
• You should see an orange-brown colour appear in the sample box in the Palette window.
• Return to the hands image, and click on the Magic wand. Set the Opacity to about 70%, and select Whole image. Click anywhere in the picture, and you'll see the colours change subtly.
• Now try pasting it back again:

  

  Welcome to Leeds