Digital photography AUG. 27, 2009 | JMC59
May 10, 2015
Digital photographyAUG. 27, 2009 | JMC59
Choosing a digital camera
What will you do with your images?
What size prints do you want to make?
How much money do you want to spend?
How “big” of a camera do you want?
Basic features
Resolution
Flash
Zoom (optical /digital)
Macro (close-up) mode
Storage (compact flash, SD card, etc.)
Know your resolution
1MP - low quality, good for screen-based images
2MP - mid-quality for computer and small prints (4x6)
3MP - good quality for color prints (8x10)
4MP - very good quality (11x14 prints)
5+MP - excellent quality (cropping photos)
Pixels and megapixels
Pixel = Picture (pix) elements (els)
Mega = million
Megapixel (MP) = million pixels
A pixel is a very small light-sensitive area
More pixels = better quality = more money
What resolution to use
Shoot at the highest resolution you will need, and consider if you will be cropping.
More realistically: if you’ve got the memory, shoot at the highest resolution you can. You can always make images smaller, but never bigger.
Resolution and megapixels
640 x 480 = .3MP1600 x1200 = 1.9MP2400 x 1800 = 4.3MP
3072x2304 or L
2048x1536 or M2
1600x1200 or M3
640x480 or S
Pixels and printing
Web site: 450x350 pixels (.25-.50 MP)
Computer wallpaper: 800x600 pixels (0.5-1.5 MP)
4x6 print: 1200x1800 pixels (1.5-2.5 MP)
8x10 print: 2000x2500 pixels (4-5 MP)
12x16 print: 2400x3200 pixels (6+ MP)
FlashWorks from a distance of 1 to 12 feet
Default — Auto Flash
Red-eye reduction
Forced flash
Night flash mode
No flash
Forced flash
Reducing red eye
Reducing red-eyeGet the flash away from the lens
Bounce the flash off the ceiling
Turn on room lights (lets pupils contract)
Use red-eye reduction flash
Have subject look slightly away from camera
Move camera closer
Don’t use flash
Or do this...
Red eye
Zoom
Optical = good
Digital = bad
Try to find a camera with at least 4x optical zoom (and ignore digital zoom)
Macro modeAllows you to shoot very close
Camera won’t normally focus that close
Memory/storage
Internal — very limited usage
Removable — Compact Flash, Memory Stick, Smart Media, Secure Digital (SD), MiniSD, MicroSD, MultiMedia Card
Review
Resolution - shoot at high or low?
Flash - do you ever need in daylight?
Close-up - what is this mode called?
Storage - what’s an example of external memory?
Photography
Literally means “writing with light”
Light is the most important thing when taking photos
Three ways to control light
Aperture: how much light gets in
Shutter speed: how long light is let in
ISO: sensitivity of image device
ApertureF-stop is the measurement of the opening
F1 is very wide opening letting in lots of light
F32 is a small opening letting in little light
ApertureYour camera likely has F3.5-F8
A full F-stop change either doubles or halves the amount of light coming into the camera
Involved in depth of field, which we will cover shortly
f 6.3
f 4.0
f 2.8
f 1.8
Shutter speed
Determines how long light comes in
1/15th of a second would be a long exposure letting lots of light into the camera
1/2000 would be a short exposure, letting in very little light
Slow shutter speeds allow blurring of the subject
Fast shutter speeds stop the action
ISO
The sensitivity of light of a photosensitive surface
Film is measured in ISO, and most digital cameras have this adjustment
Low ISO indicates low sensitivity to light, but generally higher resolution with less “noise” or “grain”
A 100 ISO setting is twice as sensitive to light as a 50 ISO
100 ISO
200 ISO
400 ISO
800 ISO
1600 ISO
Depth of field
How much of the photo is in focus
Controlled by...
Aperture
Subject’s distance from the camera
Focal length
DOF: Aperture
The more wide open the aperture, the less the depth of field
F11 aperture
F2.8 aperture
DOF: Distance from camera
The closer the subject, the less depth of field
The farther away, the more depth of field
Focal length
The greater the focal length (zoomed or telephoto), the less the depth of field
Therefore, for the greatest depth of field you would need a wide angle lens, with a closed aperture, and a subject at a good distance
Using this informationOr, using it on YOUR camera
Auto mode
When you want to take a snapshot without worrying about the mechanics of photography, leave the camera on Auto. This mode sets all exposure levels automatically, and it usually locks you out of making any minor adjustments manually.
Program mode
Like auto mode on steroids, this mode automatically sets aperture size and shutter speed for a perfect exposure — but it also lets you tweak settings, giving you more creative control. You can change white balance and exposure compensation, for instance, and even nudge shutter speed up or down a bit.
Aperture value
When you set the size of the aperture, and your camera automatically provides the right shutter speed to deliver the correct exposure. Rely on this mode to blur the background or to keep the entire image in sharp focus (depth of field).
Time value
Shutter mode: This setting is your best option for taking action photography. Shutter priority allows you to freeze the scene or artistically blur the photo. All the while, the camera keeps the exposure matched to the aperture.
Manual mode
This mode gives you total control. Exact opposite of Auto mode. You use buttons on the camera’s body to set both shutter speed and aperture size. But you are working with no safety net. The camera won’t protect you from under- or overexposed photos. Use the LED screen lots.
Landscape mode
Your camera picks the best aperture and shutter settings for the greatest depth of field when taking photos of landscapes and other outdoor photos.
Macro mode
To focus on extremely close subjects — within a few inches of the lens — choose the tulip. You can take life-size photos of insects, flowers and other small subjects in this mode. But the focus range (depth of field) is very narrow.
Snow and sand
Brightly colored or glaring backgrounds can trick the camera into underexposing the subject. This mode overexposes the scene to gain details that would otherwise be lost.
Action
The action (or sports) mode sets the camera to the highest possible shutter speed, increasing your odds of getting a clear shot of people in motion.
Night
This mode lets you capture nighttime scenes by combining a flash, which freezes people in the foreground, with a slow shutter speed, which allows lights from buildings, cars and other elements to show in the background.
< Flash
Night mode >
Portrait
This mode lets you capture portraits of people (or animals) with lower depth of field so that the background should have a soft focus.
File formats
JPG (JPEG)
RAW
RAW file format
Uncompressed
Not all manipulation programs support (Photoshop does)
On more expensive cameras
JPEG file format
Compressed
Almost all programs support
On all cameras
Lossy compression (so some data is lost)