1. Understanding Resolution &
Digital cameras

2. Understanding Resolution
Resolution is determined by how many pixels (picture elements) or dpi (dots per inch) are available.
The image you see is simply a grid of small squares or circles filled in with color. The more squares or circles—the sharper the image.
The arrow is a link to the last slide, which is a picture of a lily. A portion of the center of the lily is enlarged in the top right corner to show the pixels.

3. Measuring Resolution
Resolution is measured by the number of horizontal pixels times the number of vertical pixels
Example: x 2304

4. Megapixels
The quality of a picture is primarily measured by its resolution—how many pixels it has; the current measurement is in megapixels
A megapixel is a grid containing one million pixels (one million squares of color)—technically, that is an image with a resolution of 1024x1024 pixels

5. Three Resolutions to Consider
Image
Measured in pixels
Can be changed on the camera
High res = clear pix = large file size
Monitor
Measured in horizontal vs. vertical pixels. Ex x 768
Printer
Measured in dpi (dots per inch)
Quality of print will depend on image AND printer resolution
Question: What happens if the image resolution is higher than the monitor resolution?
Answer: You will not be able to view the image at its best quality
Question: What if the printer resolution is lower than the image resolution?
Answer: Your printed image won’t be the optimum quality. To get the optimum quality you will have to have it printed professionally.

6. Digital Cameras There are two primary categories of digital cameras
Point and shoot
Digital Single Lens Reflex (SLR)

7. Point and Shoot Cameras
Most digital cameras designed for the consumer (vs. professional) are point and shoot cameras
They fall into three categories: subcompact, compact and super zoom
The camera lenses are built-in (not removable)
Basic features typically include auto focus, auto exposure and built-in flash
Not appropriate for action photography because of lag time

8. SLR Cameras (Single Lens Reflex)
With an SLR camera, you see exactly what the lens sees
You can change the lens on a digital SLR
You choose the lens based on the type of photography; example: portrait photography vs. sporting events vs. landscape photography, etc.
SLRs produce higher-quality photos than point and shoot cameras
An SLR has a near-zero lag time, and is ideal for action photography

9. Other points to consider
When purchasing a camera, you should also research the following specifications:
Storage Capacity
Transferring Images
Power Source
LCD vs. Optical View Finder
Zoom
Image Stabilization
The Exposure Triangle (Aperture, ISO, Shutter Speed)

10. Storage Devices Memory Card Internal Memory (RAM)
The number of pictures you can take before sending them to your computer is determined by two things:
The resolution of the image
The type of storage

11. Transferring Images
Card reader
USB cable
Bluetooth

12. Power Source Regular Batteries Rechargeable batteries AC Adapter
Alkaline
Nickel-metal hydride (NiMH)
Lithium-ion (Li-Ion)
AC Adapter

13. LCDs vs ViewFinder LCD—Pro’s LCD—Con’s View Finder—Pro’s
Shows you the exact image that will be recorded
Easy to view … delete images, etc.
Displays menu
LCD—Con’s
Drains battery—uses ½ life of battery
Difficult to see in bright light
View Finder—Pro’s
Uses less battery
Easier to see images in bright light
View Finder—Con’s
Shows close approximation of the final image—not the real thing
Difficult for some people to see

14. Zoom Optical zoom actually enlarges the image
Measured in X
Example: 8X—increases an image 8 times
Digital zoom takes a portion of an image an enlarges it electronically;
The image loses resolution when the camera enlarges it; also measured in X
Macro zoom allows you to take close-up pictures of objects that are small and enlarge them so they appear larger.

15. Image Stabilization
A feature in digital cameras that reduces the vibrations that can occur when taking a picture.
Vibrations commonly occur when shooting at slow shutter speeds, with longer lenses or with digital zoom.
Also called anti-shake

16. The Exposure Triangle
Exposure is the total amount of light you let into your camera. 
Too much light results in an over-exposed image where there are areas of bright white or ”blow-outs”.  These areas contain no detail or color. 
Too little light and an under-exposed image leaves parts of your image too dark to make out details.
The three components to exposure are ISO, shutter speed and aperture

17. The Exposure Triangle
ISO—the measurement of how sensitive the image sensor in the camera is to light.
Measured in numbers 100, 200, 400, 800, etc.
Use a lower number when smooth crisp images are need and you have plenty of light.
Higher numbers are used when light is limited, you do not want to use a flash, or the subject is moving; may result in grainy images

18. The Exposure Triangle
Shutter Speed—the amount of time the shutter is open—which determines how much light is captured in the recording process
Measured in seconds: super fast 1/2000 second to 30 seconds
The slower the speed, the longer light can enter the camera. Appropriate for shooting pictures in darker situations; also great for freezing action and movement

19. The Exposure Triangle
Aperture—the camera feature that regulates the amount of light that passes through the lens by controlling the size of the opening in the lens
Described as the f/stop (a stop is a change in setting)
The smaller the number the wider the lens will open