Simulating a Zoom Burst
There are many ways to portray motion in still photography, such as panning with a suitably long shutter opening and the use of a zoom lens, zoomed either in or out during the exposure. The latter technique produces some wonderful results but the major problem is in getting the technique spot on and some folk never manage to get it just right.
Enter digital capture and Photoshop where very convincing results can be obtained which are attainable without being a genius at the keyboard. The following is a step by step through the process.
01. Open your image and using any selection tool you are comfortable with, select the element of your shot which you wish to retain as appearing static. In this example I have used the lasso tool and selected the runner.
02. Try to master the technique of making a fairly tight and tidy selection. You will probably find that using a tablet and stylus is a lot more accurate than using a mouse but with practice, mousing accurately isn't too difficult. When the selection is complete go to Select..... Feather and enter a value of about 10 pixels. The exact value will probably vary from file to file but experience will guide your thinking here.
03. Now go to Select and Inverse. This will ensure that the following actions will work only on the parts of the shot which were not originally selected.
04. Next, go to Filter.... Blur.... and Radial Blur.
05. In the pop up dialogue box, click on the Zoom button and adjust the amount slider to about 20. Then click OK to accept the settings. Note that an amount of 20 is just a guide and you may feel like adjusting this yourself.
06. If the amount is obviously too little you will have to go to Edit and Undo and start the Radial Blur step again. On the other hand if it looks a bit too strong just go to Edit... Fade Radial Blur and reduce the opacity with the slider until it looks ok to your eye.
07. When happy, go to Select..... Deselect and examine your work.
08. If you find that there are strange blemishes anywhere close to the edges of your runner (in this case) you can clean these up with the clone stamp tool.
09. Re check your work and if happy, save it giving it an appropriate name and destination on your hard drive.