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Apple Patents Directional Flash Tech For Cameras
tekgoblin writes "A patent application has surfaced that shows Apple's attempts at creating a new way for a flash to work on a camera. The way the new flash works is very intriguing: a user can select a dimly lit area of the photo and the camera will try to illuminate just that area with the flash. The way Apple is attempting to accomplish this is similar to the way the autofocus works on the iPhone 4 where you can touch the screen in certain areas to focus on that area. Instead you will be able to light up that area with the flash. This is accomplished by the camera flash passing through a 'redirector' so the flash can be placed other than directly centered when a photo is taken."
I'm a professional photographer and I've been using flash zoom, feathering etc for years to achieve this effect. Guess I won't be allowed to do that anymore without asking Apple for permission first?
http://www.meejahor.com/2008/06/06/feathering-two-lights-for-the-price-of-one/
http://www.meejahor.com/2008/09/29/feathering-its-like-off-camera-lighting-but-faster/
(Just kidding. I know it's a patent for a specific method, not the technique.)
Well it depends on which flash you're talking about.
If you're talking about the flash that comes built in on a Canon EOS Slr... The one that "pops up"... That is as worthless an Iphone flash, as it can not be aimed.
But if you're talking about a Canon 550EX Flash, which is an expensive professional grade small flash unit that mounts into the "Hot shoe" on top of the Canon EOS SLR... Those flashes can be rotated in just about every direction, including aiming it behind you... Those types of flashes are much more versatile than the "pop up" flash that comes built into the camera.
The reason is based on the physics of light.
If you've ever seen a studio photography setup, you will notice that none of the lights are attached to the camera. (Although sometimes there will be a ring flash attached to the camera.. this is a special effect I'll ignore to keep this simple)
I'm sure you've seen studio lights where theres a light thats aimed into an umbrella. This is a classic studio photography cliche that you probably have seen once in your life.
The reason you do that, is because the flash unit itself is a small light source. Small light sources cast hard shadows. If you look at most fashion photography, you will rarely if ever see a hard shadow, because hard shadows are unflattering. Hard shadows show all of the imperfections in a persons skin, and often occlude harshly areas of your subject.
So by aiming the flash into an umbrella... you are basically turning a small light source into a large light source. The reason this works is because light photons bounce from surface to surface and decrease at an exponential rate.
Firing a bright small flash into a large white surface, such as an umbrella... illuminates the umbrella and then that umbrealla becomes a source of light that casts SOFT shadows. Soft shadows, soften imperfections in skin, can fill and blend with existing light very well, and generally looks better.
So small light source = hard shadows and large light source = soft shadows. There are other fancier devices other than umbrellas. There are things called soft boxes, where instead of bouncing light off the umbrealla, you are actually shooting the light through a large transparent white surface that is encased to keep light from escaping in directions you do not want. So the lgiht only transmits out that transparent white surface... thus enlarging teh light and creating a more directional soft shadow effect. This is is the tool of choice of every studio photographer. Umbrellas work well, but soft boxes are better because they contain light and only emit it out the front. An umbrella will leak light all over your room, but it will soften the light.
ANYWAYS. I'm getting too much into this ;)
But basically an after market flash such as a Canon 550EX allows you to position the flash so that you can aim it at large surfaces around your subject, while still being attached to your camera. A pop up flash only fires in one direction... straight ahead.
An interesting thing to try if you do not own a real flash... is to simply take some kind of card, perferably white, or even better, take a piece of cardboard and wrap it in tin foil.... Now hold that card just under that pop up flash on the camera... and angle it so that it directs the light towards the ceiling. Now take a picture. You will be amazed at how more appealing it is, compared to just taking a photo with the pop up flash aimed directly at your subject. The reason is, by aiming the flash at the ceiling, you're using the ceiling as a light source, and not your flash. You've turned a small light source, into a large one, by bouncing that light off the ceiling which then bounces around the room... and eliminates the hard shadow of the pop up flash.