Altering depth of field

     To most amateur photographers one of the most baffling controls found on a SLR camera is the aperture setting.  Aperture is really the camera’s way of interpreting the preferred depth of field or more simply put, the distance from 0 to infinity where you want your image to be in focus.  It always amazes me that people will buy a thousand dollar camera and never bother to set it to anything other than the automatic mode and leave it there.  Granted I set my camera on stop action while I am moving around because photographic moments happen very quickly and stop action or the sports setting allows you to snap shoot.  You don’t have time to be fiddling with a bunch of settings while the rare double breasted, red crowned, inverted Booby Nut Hatch lands on your girlfriends head.  You have to act fast because Booby Nut Hatches just don’t have a long attention span, not to mention your girlfriend is exhibiting signs of hysteria and screaming “get this thing off me you idiot!’
     But occasionally we photographers are afforded the luxury of having a subject that will stand still while we try every conceivable camera setting we can think of in search of that award winning photo.  That brings us to the aperture setting, varying the aperture will bring one point in the distance into focus while leaving the objects closer or farther away blurry.  By doing this we can draw attention to the intended
subject we want to showcase.  Warning:  In some cases this might or might not be a good thing especially when you become so intent on getting that great shot you forget to tell your fishing buddy that he might want to throw that trout he just caught over his shoulder for good luck.  Which reminds me of just how touchy some of my friends are about how long I take to get everything just right, some people have no appreciation for the artistic process.
     Now let’s say that your reputation for the time it takes you to depress the shutter button has frightened off all your prospective subjects.  Not to worry because due to the miracle of computer photo enhancement you can use one of the high speed selections on the camera and still add depth of field latter on!  If you are careful and don’t get carried away with the amount of blur you use onl
y a real professional will be able to tell the difference between natural aperture focus and computer rendered effect.  Depending on the Photo Enhancement software you have chosen the process of creating false depth of field in your image will vary.  Most will give you a choice of applying a preset shape or tracing a custom shape using a selection tool.  I have used Corel Paintshop Pro 7 to create the effects you see in the photos that I downloaded from the web.
     In the case of the fishing image we have used the depth of field feature
effect to create an unrealistic blurring of the background in order to disguise the presence of the bear.  This kind of overuse of the effect is a great example of how too much of a good thing can be a bad thing, but I included it as a weak attempt at humor, okay so it was very weak.  Now on the other hand as can be seen in the photo of the scandalously dressed bathing beauty with the rocky coastline in the background we have blurred the coastline and thereby focused the viewer’s attention on the vixen with the umbrella.  So you can see that with the help of image enhancement software you can change the focal point of a photo to steer your viewers interest in a direction of your choosing.  By the way the photo of the young lady in the swim suit was an ad for a primitive but effective sun screen product, they called it clothes.