The lens

The quality of your photos depends on the optical qualities of the lens. There are certian criteria to take in consideration when choosing a camera with a high quality lens:

• quality of the optics
• aperture range
• minimum distance range of the lens
• minimum distortion
• optical zoom factor

However, choosing a compact digital photo camera you can not expect the lens to be of the best professional quality. There are a minimum of ‘qualities’ that the camera lens should have:

• optical zoom factor of at least 3x
• aperture starting at 1:2.8 or less (more light)
• wide angle with minimum distortion

The light capturing device

There are 2 types of devices used in digital photo cameras:

• CCD (charge coupled device)
• CMOS

It is NOT important to know what the difference is. It IS important that you know that the light reflected by your subject will be picked up by this chip that consists of millions of pixels. The sum of the light values on these pixels is called a bitmap. The result of this bitmap will be stored as the photo on the memory card of your camera.

This light capturing device is often referred to as the ‘CCD’; which is not always correct as we learnt.

The shutter and shutter release

This part of the photo camera keeps the ‘CCD’ hidden from the light. Once you push the shutter release, the shutter will be opened and expose the ‘CCD’ to the light for a very short time. The speed of the shutter depends on the settings and the amount of light available when working in automatic mode.

The shutter release (button): is the button you press with your finger to make the photo.

The aperture (or diaphragm)

Aperture or Diaphragm

This part of the camera will vary in width, depending on the settings of the photographer and the amount of light that is reflected by the subject when working in automatic mode.

It is located right behind the lens. The aperture will be wide when taking night photographs, and narrow when taking photos on a sunny beach.

The aperture is expressed in f-stops, like in the following example:

F1.4 = 1/1.4 or 1:1.4

F16  = 1/16  or 1:16

The bigger the number, the less light will pass through to the light sensitive sensor.

Lenses with f-stops f1.4, f2.8, f4, f5.6, f8, f11, f16 are very common in professional digital cameras. You can see the aperture range printed on the lens of your camera. For compact cameras the aperture range is rather limited. Sometimes between f2.8 and 5.6

Normally with the modern compact digital cameras you will not have to worry too much about f-stops. In order to know what effect the aperture width has on your photos, you need to know more about …

Depth Of Field

If the f-stop has a high number then less light will reach the ‘CCD’. But more important the ‘zone of sharpness’, as the ‘depth of field’ is often called, will be larger.

You will apply this when you want to shoot a landscape photo. The whole picture will be sharp. Also, in automatic mode when you use the predefined setting for landscape mode ,  the aperture will be small enough to make the whole picture sharp.

small aperture – large ‘depth of field’

With the aperture wide open, a low f-stop number, the ‘depth of field’ is limited. This means that when we focus on our subject, the zone before our subject and after the subject will not be sharp. This is often used when taking portrait photos with a blurred background to isolate the subject.

large  aperture – blurred background

CCD, shutter and aperture: they work together…

I will try to make this as simple as possible, but this is something you have to know about taking photos:

*Exposure Value

Exposure is determined by the sensitivity of your ‘CCD’, the aperture and the shutter speed.
You can ask 3 questions to understand this:

• How light sensitive is our CCD? (ISO)
• How wide is our aperture open? (f-stop)
• How long will the shutter remain open? (shutterspeed in sec.)

Actually there is no right exposure. Depending on what the photographer has in mind, the exposure can be chosen so that the photo looks normal, or that it expresses motion, or another special effect.

Working in automatic mode your digital camera will calculate the right exposure (EV), depending on the aperture you set or the ‘mode’ you choose . If you want to create special effects, you will have to change some settings in manual mode.

Under exposure will make your photos too dark

Over exposure will make your photos too bright.

Your digital camera has some additional manual exposure settings

You can intentionally over expose(+EV) or under expose your photos (-EV).

The LCD monitor

This is the small screen on the back of your digital photo camera. It will help you to adjust the settings before taking a photo. This monitor is used to scroll through the menus of your camera. You can also watch the photos on this monitor. However, it is not a good idea to use the LCD monitor as a viewfinder. You will hold the camera in such a way that it will easily move while pressing the shutter release. A better idea is to use the optical viewfinder.

The flash

The choice of your digital camera may depend on how powerful the flash is. Compact digital cameras have a small flash unit. This could mean that the range of your flash unit is not sufficient enough. When purchasing a compact digital camera, make sure that it has a built-in flash with a range of at least 4 meters or 13 ft.

Red eye reduction

The pupils of people’s eyes open wider in dark places. When using the flash without Red Eye Reduction the eye’s retinas red color will become visible on the photo. Although red eyes on photos can be reduced with photo enhancement software, it is better to avoid this phenomenon. Most digital cameras have a Red Eye Reduction flash setting built-in.

The memory card

This is where the camera stores the photos you take.

There are different types of memory cards used in digital photo cameras:

• Compact Flash
• Secure Digital SD
• Memory Stick Pro Duo (Sony)

There are more types, but the above are the most popular and if you buy a compact digital photo camera, you will probably use SD or Secure Digital memory cards.

At the time of writing this article memory cards of 1 GB (read 1 Giga Byte) are very common.  Depending on the preset resolution, you will be able to take at least a few hundred photos before running out of memory.

For every format there are more expensive types for sale with writing acceleration. This will make your camera faster when taking photos.