Time to click: Red eyes

While we are talking about flash this week... I thought I would take a few moments to explain why you get Red eye, (or pet eye sometimes called eye-shine - with the green or white reflections in animals), and a few ways you can prevent it!

First, lets look at what the science is behind Red Eye's.

Red-eye's in photos are effectively the reflection off of the back of an eye.  Typically you will notice them in lower light situations, or when an intense flash is used. The Flash enters the pupil from a direct angle, and reflects off the blood vessels in the back of the eye. That light then exits the eye headed back to the camera.  The closer the flash is to the lens (like shown above) the more direct the reflection path is back to the lens....

So how do you reduce, eliminate, or fix Red-eyes?

1. Change the position of your flash.

When the flash is moved away from the lens it hits the reye at an angle, and reflects back at an angle as well... just like the ball in a game of pool hitting the edge of the table. So the further away your light sorce is from your lens, the less you will have red eye from your camera to start with.  By using a flash with a bounce option you will see a drastic change in your end result.

Not only do you see the rest of the room.. but there is no more red eyes!

This is great with cameras that have an attached flash, or the ability to use an additional flash, but if you don't you will need to be more creative in your solutions!

2. Turn on Additional Lights in the room! The less intense your flash is the less chance of red eye as well. If you have the abilty to ADD light to your situation this will lessen your need for flash (or the intensity of it) and it will allow your subjects pupils to contract. Smaller pupils mean less light coming into the pupil and less light being reflected back out!

3. Use Red-eye reduction flash function.

Yep! It's what we just reviewed yesterday, and it is a functional option. The theory is that it will give eyes a chance to adjust to the brighter light allowing pupils to contract, before the flash fires. Just be sure to warn your subjects.

4. Change YOUR shooting angle.
Just because you can't change where your flash is, doesn't mean you can't change the angle of where your flash is hitting an eye! Grab a chair and shoot down at your subject, (more flattering then kneeling shooting up at them! Trust me, no one likes images shot up their nose). Or move to the left or right and have everyone look slightly over your shoulder not directly at the camera!

5. Kick up your  ISO setting.
Bet you didn't know you could change your film speed on a digital camera did you? ha! In truth its still called ISO, but its really the sensitivity of your chip and how they see light that your changing. Just like in film, the higher the number the better it is in lower light situations... but also the more "grain" or in digital terms "noise" your image will have. Typically your camera on "auto ISO" will shoot the lowest number available for the lighting situation. If your overriding.. no need to go crazy a 400 or 800 is usually just fine for most indoor situations where your still using flash. Yes, your flash will automatically know of this change and compensate by not being so intense... there for reducing your red eye!

6. Shoot, and Edit later.
Any photo editing or viewing software worth ANYTHING, has some sort of basic red eye removal tool. I personally don't like suggesting you do anything that REQUIRES you to have to spend time editing. However, it is a real option and you can choose to do it. Just promise me, like cropping you will do this on your computer for better results, no need to make your camera do it! (Yes, some have the option to do small edits like this in the camera.)

Eye Shine: While effectively the same as red eye in humans, eye-shine or pet eye is typically greenish or clear. Because some animals have the addition of a reflective layer behind the retina.  This layer is called the tapetum lucidum (Latin for “bright tapestry”).  The obvious advantage of this design is the increased availability of light for the retina. The draw back, making for poor pet photos.

This effect causes an equally haunting iridescent glow in the eyes (typically green).  Take a normally cute and cuddly creature and photograph them with a harsh flash and they will look absolutely demonic. It is also the effect behind the “deer in the headlights” look. So why, do you ask did the cat at the beginning have red eyes? Because blue eyed cat's tend to reflect red. In fact, my red tipped Siamese will shine red in regular house lights... no flash needed. Creepy right?

Unfortunately they don't like all the above solutions so well.. especially telling them where to look.  Fortunately, all the same things will work! You just have to find one your pet wont mind sitting still for!