In this picture, I have cut out the background to make it transparent.
With a transparent background, the main motive, like the fly here, becomes more like a part of the webpage. Sometimes this looks more interesting than the traditional rectangular picture.
To cut out the background, I use a photo-editing program. When I’m finished editing, I use the same program to save the picture in the png-format. Normally, I use the jpg-format, but as jpg does not support transparency, it cannot be used to make a picture like this.
There are several photo-editing programs around. I cannot afford Adobe Photoshop, so I have chosen to use Paint.Net, which is free, easy to use, and has all the tools I need. Paint.Net can be downloaded free from here. Make sure that you download Paint.Net and not any of the other programs advertised on the same page! If you need even more tools, you can try Gimp, which is also free, but much more complicated to use.
IMPORTANT: Before you start any editing, make a copy of the original picture file. Then you can edit the copy safely without the risk of ruining your original.
In this particular photo, it was easy to cut out the background (that’s probably why I got the idea, I like doing things which can be done easily). The fly was sitting on the terrace railings, which I (or my wife, rather) painted white a couple of weeks ago. So there was good contrast between the fly with shadow, and the background. Another good thing was that the background contained only one color.
In Paint.Net, there is a tool called “Magic wand”. If you choose this tool and click somewhere in the picture, the whole area in the picture which contains the same color as where you clicked, will be selected. When an area is selected, you can choose Edit->Cut to delete it, and it will be replaced by an area which is transparent. So that’s the trick, really. Click somewhere in the background you want to remove, check the area which is selected, and use Edit->Cut if you are satisfied with the selection. You may have to do this in several steps, to make sure that the program does remove exactly what you want it to. There is a “Tolerance” adjustment to play with, it has the shape of a slider which is set to 50% as a default. You may also want to use the Eraser tool to do the final make-up. You can zoom into the difficult places and really do some meticulous editing if you want to.