theory

Colour Space:

Colours in photoshop are shown as little squares.

Colour space is how the colours are used in an image.

they are pieces of light through a screen.

Three colours:

The three colours used in photoshop are Red, Green and Blue.

These three colours are the primary colours of light.

The colours are broken up for us to see. 

There are 256 tones in these colours.

The lightest colour of all three is white. and the darkest black.

Print:

C M Y K are the printing colours.

They stand for, cyan, Magenta, Yellow and Black. 

When printing there aren't as many colours to choose from than in light.

When you print something it prints 4 times to include al 4 colours.

Gamut is the range of colours in an image.

If its out of range it can't print. 

Pixels:

They are single small squares.

Each square includes R G B each at a certain tone.

Ive uploaded this picture to photoshop. this is the original.

This is the photo without any red channels in it.

 Now the photo without any green channels.

Lastly without any blue channels.

How much a photo takes up, the size of this can be measured in:

• file size
• Document
• Pixel size = 72 pixels per inch

optimum resolution is always best.

pixels per inch matches up to the amount of pixels on your screen. 

You only measure in dots when you are printing. 

When printing to make the printing faster and the picture clearer, take away all of the layers apart from the original. The best size for print is 300ppi.            

A photo of a snake with 72 ppi.