20,982 views

The Angle of Incidence Equals the Angle of Reflection

Often the Law of Incidence Equals the Law of Reflection is used to fill the "micro pores" of the face using this over/under lighting technique.  In this case, the ringflash fills the pores of the face since the camera is mounted on it.  The main light is slightly higher in power output above the ring flash.

Often the Law of Incidence Equals the Law of Reflection is used to fill the “micro pores” of the face using this over/under lighting technique. In this case, the ringflash fills the pores of the face since the camera is mounted on it.

The main light is slightly higher in power output above the ring flash.  The beauty dish is directly underneath to provide a “kicker” light, or softening of the shadows.  The photographer is shooting through a ring flash between the beauty dish and the main light above.

In physics, the law of reflection states that the angle of incidence is equal to the angle of reflection. This tenet is fundamental to the understanding of light and can be summarized thusly: if light strikes an object at angle A, it will be reflected in the opposite direction, also at angle A, similar to the way a ball bounces off a brick wall. In photography, the law of reflection is rarely discussed; one typically hears more about the Inverse Square Law or that white reflects and black absorbs. While these are indeed important aspects of light, the angle of incidence and the angle of reflection are two components of physics that, once understood, can help photographers improve their images they create in both artificial and natural light.

The easiest way to comprehend this concept is to go into a place that has hard, shiny floors and overhead lighting (grocery stores work great!). Look down while you walk and you’ll see hot spots of light on the floor move with you as you walk. These hot spots are the direct reflection of the overhead lighting, and they evidence the law of reflection. These equal angles of incidence and reflection can cause hot spots on your subject too. Understanding the law of reflection will help you avoid hot spots on your subjects, whether you are photographing models, cars, food, or landscapes. In fact, managing these equal angles of reflection in your photographs allows you to add or eliminate texture and color in your images.

The white spots or highlights in this image of candles is where the angle of incidence is equal to the angle of reflection, thus the hot spots.

The white spots or highlights in this image of candles is where the angle of incidence is equal to the angle of reflection, thus the hot spots.

The law of reflection is also responsible for the red-eye effect that plagues ring flash users when shooting through the ring. Because the camera’s lens is at the same angle to the subject as the flash, the reflection of light against blood vessels in the retina at the rear of the eye produces red-eye. An easy way to eliminate red-eye is to brighten the room; this causes the subject’s pupils to contract, thus greatly reducing any reflection. Another method is to take a monolight with a 7-inch 20 degree grid and point it at your subject’s face with only the modeling lamp powered on (not the flash unit itself). Many flash units, including the Broncolor, Hensel, and Profoto brands have separate switches for the modeling lamp and electronic flashtube, allowing them to be powered separately.

The law of reflection is especially troublesome when glass or mirrors are present in the image. The equal angles of incidence and reflection cause hot spots in glass and mirrors when using a flash. The simple solution is to move the flash away from the camera so that the angles are not identical.

In the studio, you can use the monolight red-eye reduction technique described above in a darkened room. This will allow you to show more of your subject’s iris and less of their dark pupils. The technique works well with light-colored eyes, especially green and blue. Don’t be alarmed by the appearance of harsh shadows on one side of the nose, as the power of the artificial flash will knock this out when it fires

The stars created in the crystal flower are because the angle of incidence is equal to the angle of reflection.

The stars created in the crystal flower are because the angle of incidence is equal to the angle of reflection.

By moving the camera and light source(s) independently, you can use the law of reflection in your favor, almost like an added layer of makeup to smooth your subject’s skin. As you walk around your subject, you will notice that hot and washed out spots will appear and disappear based on the angle of reflection. You may also notice that your model’s face appears smoother from one angle and rougher from another angle, as the valleys of the pores are filled in with shadows. Through positioning your camera and light sources independently, you can eliminate hot spots and create the appearance of a smoother skin texture.

Because the vast majority of what we see is reflected light (as opposed to incidental light), we as photographers live in an illuminated world. Without light, we would have no images to capture, and humans would see nothing but perpetual blackness. Understanding the law of reflection will allow you to outshine your competitors, as your photographs will take advantage of one of the fundamental laws of the universe and stand out from those created by your peers.  Well that’s it for now, please don’t forget our military troops, their families and friends, as they all sacrifice to keep our nation strong and free–God Bless! Rolando

Arizona Immigration Law, The New INS

I rarely publicly get into politics, it’s just not good business when you work for yourself to take a political side, but I’ve got to chime on this controversial Arizona immigration law—at least from an American of Latin descent observation of things. There is so much information, misinformation, debates, etc., out there where everyone is split over this new law, and that’s what bothers me the most.  If millions of people can’t come to agreement on how to interpret the law, how can an Arizona lawman be smarter than the rest of the world? And I’m just curious if all law enforcement types in Arizona have undergone specialized immigration training in how to define “reasonable suspicion” when it comes to determining if someone is an illegal alien?

According to this new state immigration law, law-enforcement officials in Arizona have the right to determine the immigration status of a person “where reasonable suspicion exists that the person is an alien who is unlawfully present in the United States.” And if that person can’t prove their status, then they “could be arrested and jailed for six months and fined $2,500.”  (Note: It’s been rumored that TMZ hopes to catch Sheriff Joe Arpaio of Maricopa County at Home Depot—you know, buying saws, hammers and two-by-fours for his new expansion project.)

Now this is where I have a problem, and I’ll explain from my 47-years of being a Texan born in the good ole US of A with Latin descent.  Growing up as a kid, even with my Spanish heritage, European white-skin looks, I was often called a wetback, spick and all those racial names—in Texas. The darker-skinned Latinos would call me a Gringo and once I told them my last name, I was called a Güero. So most people when they see me don’t think I’m Latino until I introduce myself.

Then I’m asked, are you Hispanic? My first response is, “Where is the country Hispain? No, I’m of Latin descent, born in Texas, and served patriotically for over 8-years active-duty in the U.S. Army plus 8-years more as a civil service employee in the U.S. Air Force. So I tell them, “I’m an American and Texan of Latin descent.”

Right after I provide that answer, not surprisingly, I get the next dumb question, “Are you Mexican-American?” My response, “Nope, I’m an American of Latin descent.” Then I ask them, what descent are you from? Usually I’ll get German, Italian, Polish, etc., you get the picture, so then I say (matching the right descent to the person), “Are you German-American, Italian-American, Polish-American?” Get the picture?  And somehow Arizona law enforcement officers are supposed to be smarter than the Texas Rangers and the rest of the world? Don’t get me wrong, I support law enforcement but feel interpretation of the law, especially immigration law, should be left to those trained and specialized in it.  Heck, in Texas we have board certified lawyers in immigration and Spanish Land Grants.

Let me give you a better analogy, would you let a plastic surgeon do your heart transplant because both are doctors and surgeons?  Would you let a divorce lawyer represent you in a murder trial? Maybe if you were Tiger Woods or Jesse James. And you wonder why Sandra Bullock filed for divorce in Texas. Meanwhile back to the ranch.

In my opinion it seems that the Arizona legislators are targeting the “Mexicans” which sounds like racial profiling. If it walks like a duck, quacks like a duck, then it’s a duck!  If they are not racial profiling one specific group, then will they stop someone because they look Asian?  I’m willing to bet money, that Officer Brewer, no relation to Arizona Governor Jan Brewer, since she is Caucasian (I bet some of you thought Officer Brewer was a man), will never ask a “Caucasian” person in Scottsdale for their proof of U.S. citizenship, though that same officer would ask Juan Valdez immediately when they spot him at Starbucks ordering Columbian coffee. Though I’m wondering how many law enforcement officers in the United States realize that the term Caucasian refers to white-skinned Europeans? (Source, Wikipedia.com)

Maybe as part of the training of law enforcement in Arizona we should include something like a Coke verses Pepsi taste-test trial and place an Caucasian next to an American of Latin descent (dark-skinned) and see how many officers would pick the Caucasian out of the line-up?  God forbid if the surrounding states of Arizona pass the same law. New Mexico will have some serious problems trying to distinguish real Mexicans from new Mexicans—somehow I picture a lot of their lawmen drinking margaritas after work.  Nevada shouldn’t have any problems though if public perception is correct and Area 51 comes to life, just look for green colored skin—now that would be an irony if those green illegal aliens got pass the Arizona police and crossed into New Mexico.  Then you’d have a New Mexican Caucasian police officer calling aliens Greengos.

Going back to my military days, it’s against the law for the U.S. Military to act as “civilian” law enforcement–yes, I spent 26-months in the Latin American drug war during my soldier time in the early 90’s, so I know that law well as it was never left up to our interpretation. So if it’s against the law for a U.S. Army soldier to act as civilian law enforcement, especially immigration law, why then under Arizona law, are they allowing the local yokals–the type that can “flash their tin” to break speeding laws when off-duty, to question anyone “reasonably suspicious” when it comes to citizenship status?

Does suspicious mean the same to Officer Felipe Calderon as it would to Officer Jan Brewer? Would Officer Calderon always pick out a Caucasian and Officer Brewer a Hispanic or Asian?  Get the picture? Just like the Federal government requires it’s workforce to undergo sexual harassment and suicide prevention training, why shouldn’t Arizona require all it’s peace officers, for the sake of peace, to undergo racial profiling training? Just what does an illegal alien look like that makes them suspicious?

Bottom line–let INS do their job. Local police are already overworked and now you’re giving them immigration duties? Doesn’t make sense. The next Arizona law will give police officers the right to question anyone with a cigarette lighter because they could be an arsonist. Even President Barack Obama strongly criticized the law and is calling for Federal immigration reform—our President people.  I wonder where Sheriff Joe Arpaio of Maricopa weighs in on this, at least he had the sense to make prisoners pedal to generate electricity to power TV sets in jail.  I’m willing to bet, “America’s toughest Sheriff,” as he’s commonly referred too, is building a whole new tent city in anticipation that he’ll run out of room and the dinner menu I can assure you is not Kung Pao Chicken or enchiladas.

Well I’m in Arizona next month to conduct a photography workshop, guess I’m going to take my U.S. Passport and put it in my briefcase because if my wallet gets stolen, I could be locked up since my last name is Gomez and not McCain, thus suspicious to someone that is not Latino and doesn’t understand the Latin culture. Like Carlos Mancia would say, if you’re drinking a beer or standing outside Home Depot you have provided enough reasonable cause to look suspicious so thank goodness I drink Canadian, Crown Royal Reserve and not beer and I prefer Lowes hardware stores. Speaking of Canadians, I hope Phoenix Suns player Steve Nash (Canadian) gets pulled over (and is not carrying any identification) on the way to the U.S. Airways center tonight when they meet the San Antonio Spurs for round two of the NBA Playoffs—though I wouldn’t wish the same for Tony Parker or Manu Ginoboli.

I close by saying, let’s not go back to WWII where in Europe you had to carry papers. The Arizona immigration law is just another “persecution” of another ethnic group, which is worse than racial profiling. So I’ll agree with Arizona Governor Jan Brewer, it’s not racial profiling—it’s persecution. If there is any good news in this for Arizona, the Diamondbacks aren’t changing their name to the Yankees, probably because they got more baseballs than Arizona Tea, which is scrambling to tell the world it’s brewed and based out of New York—seriously. Just my two centavos for what it’s worth.  Thanks to reading my rambles and as I always say, let’s not forget the men and women in the military and their families as they sacrifice more to protect our freedoms than anyone in this great nation.  God Bless, Rolando