Digital Cameras

Camera Phone
Camera phones can't make very high quality pictures, but they are useful because they are small and easy to fit into your pocket. Cheap mobile phone with camera will cost on average about £30. An iPhone with camera would usually cost £600. Camera phones can't make very high quality pictures because they use digital zoom and when you zoom in, it enlarges the pixels making the picture quality not as good.

Compact Camera
Compact camera (also called a point-and-shoot camera) is digital and easy to use because they're small. A lot of compact cameras use autofocus to really focus on the object for more detail and sharper, better quality. The zoom feature is good because it uses optical and not digital zoom. Optical doesn't make the pixels bigger. The lens of the camera moves outwards for zoom and the quality is much better. To buy one, the prices are usually around £50-200.

DSLR
DSLR is short for Digital single-lens reflex camera. DSLR camera is for professional photographers who want to take the best quality pictures because they can sell them. DSLR camera is customizable e.g. you can change the lens to bigger for better zoom. The lens are really long as well so they can zoom much better than compact cameras. Most DSLR cameras are big so they have to be carried around in a suitcase which is a disadvantage for them. They cost around £400.

Graphics Tablets

What is a graphics tablet?
A graphics tablet is similar to paper and pen, but it's for PC. Anything you write or draw on the graphics tablet, will show up on the PC. This is good because it's easier to draw with than using a mouse. It plugs into the PC using a USB port.

Different types
The expensive graphic tablets are easier to use because it has it's own screen and unlike the cheaper graphics tablet, you don't have to keep looking at your computer screen. You can buy some graphic tablets with screen for quite cheap, but it might be cheap because it's not very sensitive.

All graphic tablets use pressure sensitive surfaces, but some are more sensitive than others which effects the prices; cheaper graphic tablets are less sensitive.

Costs
You can buy a cheap graphic tablet for about £40-50 and if you want a graphic tablet with screen, it'll cost about £800-900. (Prices from Amazon UK and PC World)

Things to look for
Size could matter because if you want to draw a A4 size picture, you'll be a lot better off with a graphic tablet with a A4 sized pressure sensitive surface because with a smaller (A6) sized graphic tablet, you'll have to keep move the pen back because there isn't enough space. You might also need a sensitive graphic tablet because it can pick up more detail, e.g. harder you press, the sharper the picture will look like pencil on paper.







Lossy & Lossless

What is lossy?
Lossy is when you reduce the size of a file and doing this, the quality of the file will be weakened because some of the file's information is automatically thrown away.

 

                  (PNG file)                                       (JPEG image)

If you look at the image of the dog on the left, the quality is good, but the file size is 60.1 KB. However if you look at the image of the dog on the right, the quality is bad, but the file size is 1.14 KB.

(JPEG image 2)

JPEG image 2 is only 4.82 KB in size, but the picture's quality is almost similar to the PNG file. This is because the human eye can't pick up all the pixels. You can reduce the size a lot and the quality will be okay, but not too much because it will look like JPEG image 1. JPEG image 2 is okay because it's a lot smaller in size which will save space and the lower quality won't be that noticeable to the human eye. Reduce the image too much, it won't be any good and once it's thrown away all the information, you can't get it back again.

What is lossless?

Lossless is taking the image and reconstructing it, making it smaller, but keeping it identical to the original. When you re size the image back to its original size, the quality of the image will go back to the original quality because it never lost any of its data / colouring.