![angle of reflection angle of incidence mountain picture angle of reflection angle of incidence mountain picture](https://image2.slideserve.com/4354124/slide7-l.jpg)
Photons that are in phase (all the photons that are emitted upwards) will constructively interfere with eachother. Photons that are out of phase will tend to cancel eachother out. The photons that are emitted at an angle however, will be out of phase with eachother (since there is a distance between the electrons, if two photons are emitted at any angle at the same time, there will be a slight delay between them). Now you have many electrons that are being bombarded by even more photons, all emitting photons in many directions. Let's assume that the beam of light hits the reflecting surface directly from above, so the angle of incidence is 0 degrees. Hint: this is where the wave nature of light comes into play. If this is the only electron in the neighbourhood that releases a photon, it will go in any random direction. When it does, it needs to get rid of its extra energy. This chance increases over time, so it's pretty certain that it will jump back quite quickly. Thus, there is a chance that it spontaneously jumps back to a lower energy state. This does not last long the electron left an "empty" energy state below it, which is an energetically more favorable position for it.
![angle of reflection angle of incidence mountain picture angle of reflection angle of incidence mountain picture](https://rmico.com/images/stories/Catalog/TechNotes/critical-angle.gif)
When a photon hits an electron, its energy gets absorbed and the electron goes into a higher energy state. It runs into a wall of atoms - lots of nuclei surrounded by electrons (also energy packets - there's more to it but let's not write out all of quantum mechanics here). Now let's zoom in and look at what happens when the photon hits any material. Not because we must, but because we can! There's a TL DR below.Ī beam of light can be thought of as a stream of energy packets (photons, which are the quanta of light - lots of interesting words to look up in the dictionary already). However, to quote Leonardo DiCaprio: we need to go deeper. It’s about compromise ultimately, and you can always try tilting the glasses or try a different pair to see if that helps.The answer by harshit54 is very concise and clear and gives you answers in multiple layers of understanding. Of course, as Gavin says in the video, it won’t necessarily mean that the light source is in the most ideal position for the portrait. Move your light source around if you can until you can no longer see the reflection in the camera. Phew! Sounds complicated, but actually not so much in reality. That basically means that the angle that the light is hitting the glasses needs to be different from the angle the camera is viewing the glasses in order to not see the reflection of the light source. So after all of that playing around with reflections, what do you do if you want to eliminate the reflections after all? Well, its simple, and also not so simple if you’ve ever tried it! Remember the rule the angle of incidence equals the angle of reflection. You could even get fancy and try using a gobo! A larger light source will look different than a smaller one, and equally different shapes will produce different effects.
![angle of reflection angle of incidence mountain picture angle of reflection angle of incidence mountain picture](https://i.pinimg.com/originals/45/0e/8d/450e8df4d1dfc6c4f356cb4a616b49f9.png)
Also, experiment with different sizes and shapes of light sources. Bonus tip: Try adding a diffuser in front of the light to add a subtle gradient to the reflection.Try different types of sunglasses as they all have different curves and that will affect the way the light reflects off them.If you don’t want the subject looking up, just move the light lower so that it’s in line with the eye line. Try using a single round light overhead and ask your model to look up.This way you can guide your model into the right position to get the effect you’re after, or simply reposition the light. Use the modelling lamp (if you have one) to see what you’re getting before you start taking photos.You can use another light behind the model to light up the backside of the head and create more interest and separation from the background. Try a side profile portrait: Position the light in front of the model until you see the reflection in the centre of the sunglasses.
![angle of reflection angle of incidence mountain picture angle of reflection angle of incidence mountain picture](http://rmico.com/images/stories/Catalog/Coatings/vis-nir-bcb.gif)
Gavin says that usually, we try to avoid reflections in glasses and sunglasses, but sometimes it just looks great, and it’s worth taking the time to experiment and see what you can get.