Is Bob Marley despicable?

Well the answer is no, I don’t suppose he is.

But as any of you who have been reading my blog will realise – its not going to be about Bob Marley at all – but of course there will be a connection.

If we play word association and I say Bob Marley – what might you say? (remember your answer A).

Chill out to this  – 
while you read on . . . .

Now if I play word association with my 7 and 4 year old boys and I say Despicable – then not too far down the line we would probably get to (answer B) . . .

Clues here to what I am getting at
or video:

OK answer A was Rasta  – Answer B was Vector

Rasta – or (to put it in the design context) Raster is the term used for files created with pixels.
You will be familiar with those if you have read the last few blogs.

And Vector – (besides being the amusing villain in the despicable me movie) is also the term for files created using lines.

There are pros and cons for using either format, but the point is that it is handy to be aware of those pros and cons, and the aim of your file and the limitations.

I have talked particularly in blog 25 ( Once upon a pixel . . .(tech 1)) about how raster images are made up of little tiny coloured blocks called pixels and how these pixels are used by a screen at 72 every inch, but by a printing press at 300 for every inch.

This thereby dictates the need to know in advance what you want the raster file to be used for and to create it to the maximum size to cover all eventualities.

While you can throw information away without losing quality – you absolutely cannot scale up the dimensions on a raster file to make the image larger.
(the pixels are supposed to be small enough to be undetected by the eye – and if you enlarge your image so that you can start to see them – then its not right . . . .)

. . . . Possibly with the only exception being if you particularly intended to create some kind of artistic design effect by purposely doing this.

With a vector file however, it is made up of lines – like you seven year old drawing cars on a sheet of yellow paper before school (this morning) –

and those lines can be filled in with blocks of colour, or blends of colour, or tints of colour.
And the lines can be coloured themselves.

With a vector file you can scale the image up as much as you like and you will not lose any quality – it will be as sharp as ever.

You can also extremely easily convert your vector file into a raster file when you have finished it – should you need to have the flexibility of having it in a raster format.

While you can place a raster image within a vector document, you cannot convert it to a vector format. It will have to be re-created – traced over, re-drawn.

And a vector file takes up a lot less computer memory too – it is to do with how the information in the file is saved.

Draw A 1 cm red square centred on a 2.5cm white background.
and from that amount of information you know what I mean and can draw the red square.

And that is (in essence) all the information that the vector file needs to remember.

The raster file however is made up of pixels (historically counted up to inches) so an image for a screen at 2.5cm (or 1 inch) would contain 72 pixels horizontally and 72 pixels vertically making a whopping total of 5184 pixels.

So the same red square on a white background file is made up of 5184 pixels and the information stored in the file has to contain what colour each of those pixels needs to be.

So vector file information: 1 cm red square centred on a 2.5cm white background.

Raster file information: row 1- pixel 1 = white, row 1- pixel 2 = white, row 1- pixel 3 = white, row 1- pixel 4 = white,  . . . . etc (up to 72 per row)
. . . . . . . . row 22 – pixel 22 = red, row 22 – pixel 23 = red
Basically a heck of a lot of information to store.

So consider this, if you then scale that image up larger to a 10cm square: (which you can because its just a red square)

The vector file information becomes: 4 cm red square centred on a 10cm white background.
but the raster file now has 82,944 pixels to remember.
(and because it is made up of pixel information it has to guess whether to put red or white into the additional 77,760 pixels, and if it makes a mistake then your red square could end up as a rectangle – or worse!

So I would recommend – particularly if you are creating a logo, emblem, badge – any element that you may need to enlarge at an unknown later date then use a vector format. (To be fair, most software is vector anyway). It will give you more scope for future projects.

Anyway I hope that this simple explanation helps to go a little way to understand why, in design terms generally Bob Marley might actually be a little bit despicable after all.


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