Tuesday, April 27, 2010

The thing about depth Of field

Depth of field is a big deal because it directly affects the composition, acceptability, desirability, and general artistry of your images.

Depth of field refers to the parts of the scene in focus in front of and behind the subject.

Sometimes you want the depth of field to be so shallow that the background is entirely blurred with no definition at all.

That directs a viewer’s attention where you want it.

Background vs. foreground

Out-of-focus backgrounds are not only acceptable, but often desirable.

However, out-of-focus foregrounds can be unattractive and even distracting.

For an out-of-focus foreground to look right, it should be just a blur of color.

Four factors when you shoot:

1. Lens focal length. The longer the focal length, the less depth of field in the image. On the other hand, as the focal length shortens, depth of field increases. Long telephotos have very shallow depth of field.

2. Lens aperture. As the lens closes down to a small opening, depth of field increases toward the maximum the lens can provide. When you choose to use large lens apertures, you lose depth of field.

3. Distance to the subject. When you move in close to a subject, such as when doing close-up or macro photography, or when you want to fill the frame with a small object, depth of field decreases. On the other hand, as you back away from the subject, depth of field increases.

4. In close-up or macro photography, placing the camera so its back is parallel to the subject, increases depth of field. When the camera back is slanted to the plane of the subject, depth of field is reduced.

There is a shot where you don't have to worry about depth of field. Everything will be in focus at any lens aperture when the elements in the scene are far away. Large lens apertures give you shallow depth of field. However, a wide-angle lens has tremendous depth of field so more of the picture comes into focus.

As usual, a tripod helps

When you close the lens down to use a small aperture, less light enters the camera. The lightmeter must compensate for the light loss to maintain a correct exposure. The shutter speed becomes longer. A tripod steadies the camera, reducing the possibility of blurring images of stationary objects.

When you move in very close to small objects in macro photography, depth of field becomes limited by the shooting distance between the subject and lens. Small apertures often are used in close-up photography to recover that loss in depth of field. That forces the use slow shutter speeds. Use a tripod when doing macro photography. Otherwise, the photos will be blurred or else have very shallow depth of field.

The same is true when using a long telephoto lens. Any movement will be magnified in the lens and a tripod would stabilize the camera and lens for a sharp image.

Tuesday, March 30, 2010

Water droplet reflections

Adding water can make your flower images seem mysterious and more attractive. Here's how to grab the reflections in water droplets.

Shooting after a rain shower provides natural raindrops. On the other hand, you can create your own raindrops with a spray bottle of water.

Spraying water

After a rain, go out and look for raindrops or, if no rain, use the spray bottle of water.

If you continually spray a flower, water will accumulate in certain places to form large drops. This may give you more control because you can spray from different angles if you want a raindrop in a certain area.

Some photographers use glycerin in an eyedropper to place their droplets where they want. Glycerin is sticky, so your droplet will hold on better, but it's also more difficult to move. Don't get your camera sticky!

Shoot outside on a day with no wind.

Steady tripod

Place a tripod low to the ground.

Shoot in macro with a narrow depth-of-field. Use a macro lens or macro setup with a telephoto lens with extenders.

Put the camera on the tripod with the macro lens focused on your raindrop or water droplet.

Use something you devise to hold the flower or flowers firmly in place.

Move in close

Move your view in so close that you see the flower reflected in the raindrop or water droplet.

Focus on the reflection inside the raindrop, not the contours of the raindrop.

If you accidentally bump the flower and knock the raindrop off, spray on some new droplets.

See the reflection

Make sure you are able to see through the droplet so a reflection appears. You won't want to merely photograph the surface of the raindrop. Instead, shoot through it.

Pick a raindrop or water droplet with minimum glare. Avoid highlights which will reduce the vividness of the reflection.

With the camera mounted firmly on the tripod, compose a picture with S or C curves so the image seems to flow.

Focus the macro lens on the center of the water droplet, where the flower reflection appears.

A blurry background will provide a pleasant image of the in-focus droplet and reflection.