CONCEPT: FLASH RATIO

CONCEPT: FLASH RATIO

The "flash ratio" is an important way to describe the mix between ambient light and light from your flash. Since the shutter speed doesn't affect the amount of light captured from your flash (but does affect ambient light), you can use this fact to control the flash ratio. For a given amount of ambient light, the mix of flash and ambient light is adjusted using only two camera settings: (i) the length of the exposure and (ii) the flash intensity.

                                                Flash Ratio:    N/A or 0
                                                                           Only Ambient Light
                                                     Settings:        no flash

                                                                     1:8 - 1:2
                                                                            Fill Flash
                                                                       longest exposure
                                                                         weakest flash
                                                                           1:1
                                                                   Balanced Flash
                                                                  shorter exposure
                                                                     weaker flash
                                                                          2:1 - 8:1
                                                                        Strong Flash
                                                    shortest exposure
                                                                      strongest flash

In this tutorial, the flash ratio* is used to describe the ratio between light from the flash and ambient light. At one extreme of this ratio is ordinary ambient light photography (left), and at the other extreme is photography using mostly light from the flash (right). Realistically though, there's always some amount of ambient light, so an infinite flash ratio is just a theoretical limit.

*Technical Note: Sometimes the flash ratio is instead described in terms of the ratio between total light and light from the flash. In that case, a 2:1, 3:1 and 5:1 ratio would be equivalent to a 1:1, 1:2 and 1:4 ratio in the table above, respectively. Unfortunately both conventions are used.

It's important to also note that not all flash ratios are necessarily attainable with a given flash unit or ambient light intensity. If ambient light is extremely intense, or if your flash is far from your subject, it's unlikely that the internal flash of a compact camera could achieve flash ratios approaching 10:1, for example. At the other extreme, using a subtle 1:8 fill flash might be impractical if there's very little ambient light and your lens doesn't have a large maximum aperture (or if you are unable to use a high ISO speed, or capture the photo using a tripod).

Flash ratios of 1:2 or greater are where the topics in the first half of this tutorial become most important, including the flash position and its apparent light area, since the flash can appear quite harsh unless carefully controlled. On the other hand, flash ratios less than 1:2 can often achieve excellent results using a flash that is built into the camera. For this reason, most photographers will likely want to use their flash as a fill flash, if possible, since this is the simplest type of flash photography.

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CAMERA FLASH: EXPOSURE

CAMERA FLASH: EXPOSURE

Using a camera flash can both broaden the scope and enhance the appearance of your photographic subjects. However, flash is also one of the most confusing and misused of all photographic tools. In fact, the best flash photo is often the one where you cannot even tell a flash was used. This tutorial aims to overcome all the technical terminology in order to focus on the real essence of flash photography: how to control your light and subsequently achieve the desired exposure.
The first part of the camera flash tutorial focused on the qualitative aspects of using a camera's flash to influence a subject's appearance; this second part focuses on what camera settings to use in order to achieve the desired flash exposure.
FLASH EXPOSURE OVERVIEW
Using a flash is fundamentally different from taking a normal camera exposure because your subject is being lit by two light sources: your flash, which you have some control over, and the ambient light, which is likely beyond your control. In this part of the tutorial we'll focus on the other two consequences of this fact, as they pertain to flash exposure:



Illustration shown roughly to scale for a 1/200th second exposure with a 4:1 flash ratio.
Flash shown for first curtain sync. A pre-flash is not emitted with much older flash units.

  1. A flash photograph actually consists of two separate exposures: one for ambient light and the other for flash. Each of these occurs in the split second between when you hold the shutter button and when the shutter opens. Newer SLR cameras also fire a pre-flash in order to estimate how bright the actual flash needs to be.
  2. A flash pulse is usually very brief compared to the exposure time, which means that the amount of flash captured by your camera is independent of your shutter speed. On the other hand, aperture and ISO speed still affect flash and ambient light equally.



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10 Tips for Great Pictures

10 Tips for Great Pictures

Do you wish you were a better photographer? All it takes is a little know-how and experience. Keep reading for some important picture-taking tips. Then grab your camera and start shooting your way to great pictures.


  1. Look your subject in the eye
  2. Use a plain background
  3. Use flash outdoors
  4. Move in close
  5. Move it from the middle
  6. Lock the focus
  7. Know your flash’s range
  8. Watch the light
  9. Take some vertical pictures
  10. Be a picture director

Look your subject in the eye
Direct eye contact can be as engaging in a picture as it is in real life. When taking a picture of someone, hold the camera at the person’s eye level to unleash the power of those magnetic gazes and mesmerizing smiles. For children, that means stooping to their level. And your subject need not always stare at the camera. All by itself that eye level angle will create a personal and inviting feeling that pulls you into the picture.

               
                                            Better                                              to high

Use a plain background
A plain background shows off the subject you are photographing. When you look through the camera viewfinder, force yourself to study the area surrounding your subject. Make sure no poles grow from the head of your favorite niece and that no cars seem to dangle from her ears.

                           
                        Distracting background                                                    Better

Use flash outdoors
Bright sun can create unattractive deep facial shadows. Eliminate the shadows by using your flash to lighten the face. When taking people pictures on sunny days, turn your flash on. You may have a choice of fill-flash mode or full-flash mode. If the person is within five feet, use the fill-flash mode; beyond five feet, the full-power mode may be required. With a digital camera, use the picture display panel to review the results.

                            Subject is dark                                                               Better

Move in close
If your subject is smaller than a car, take a step or two closer before taking the picture and zoom in on your subject. Your goal is to fill the picture area with the subject you are photographing. Up close you can reveal telling details, like a sprinkle of freckles or an arched eyebrow.
But don’t get too close or your pictures will be blurry. The closest focusing distance for most cameras is about three feet, or about one step away from your camera. If you get closer than the closest focusing distance of your camera (see your manual to be sure), your pictures will be blurry.

                                 Good                                                                     Better

Move it from the middle
Center-stage is a great place for a performer to be. However, the middle of your picture is not the best place for your subject. Bring your picture to life by simply moving your subject away from the middle of your picture. Start by playing tick-tack-toe with subject position. Imagine a tick-tack-toe grid in your viewfinder. Now place your important subject at one of the intersections of lines.
You’ll need to lock the focus if you have an auto-focus camera because most of them focus on whatever is in the center of the viewfinder.
                              Boring                                                                     Better

Lock the focus
If your subject is not in the center of the picture, you need to lock the focus to create a sharp picture. Most auto-focus cameras focus on whatever is in the center of the picture. But to improve pictures, you will often want to move the subject away from the center of the picture. If you don’t want a blurred picture, you’ll need to first lock the focus with the subject in the middle and then recompose the picture so the subject is away from the middle.
Usually you can lock the focus in three steps. First, center the subject and press and hold the shutter button halfway down. Second, reposition your camera (while still holding the shutter button) so the subject is away from the center. And third, finish by pressing the shutter button all the way down to take the picture.

   
                                   focus                                                              Subject not in focus

Know your flash's range
The number one flash mistake is taking pictures beyond the flash’s range. Why is this a mistake? Because pictures taken beyond the maximum flash range will be too dark. For many cameras, the maximum flash range is less than fifteen feet—about five steps away.

What is your camera’s flash range? Look it up in your camera manual. Can’t find it? Then don’t take a chance. Position yourself so subjects are no farther than ten feet away. Film users can extend the flash range by using Kodak Max versatility or versatility plus film.
                
    
                 without flash                                                                     with flash
Watch the light
Next to the subject, the most important part of every picture is the light. It affects the appearance of everything you photograph. On a great-grandmother, bright sunlight from the side can enhance wrinkles. But the soft light of a cloudy day can subdue those same wrinkles.

Don’t like the light on your subject? Then move yourself or your subject. For landscapes, try to take pictures early or late in the day when the light is orangish and rakes across the land.

           
                       Goog                                                                Also good

Take some vertical pictures
Is your camera vertically challenged? It is if you never turn it sideways to take a vertical picture. All sorts of things look better in a vertical picture. From a lighthouse near a cliff to the Eiffel Tower to your four-year-old niece jumping in a puddle. So next time out, make a conscious effort to turn your camera sideways and take some vertical pictures.
                      
           
                                                Good                                                            Better

Be a picture director
Take control of your picture-taking and watch your pictures dramatically improve. Become a picture director, not just a passive picture-taker. A picture director takes charge. A picture director picks the location: “Everybody go outside to the backyard.” A picture director adds props: “Girls, put on your pink sunglasses.” A picture director arranges people: “Now move in close, and lean toward the camera.”

Most pictures won’t be that involved, but you get the idea: Take charge of your pictures and win your own best picture awards.


      
                             Boring                                                                       Better




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