One of the hardest parts of my job is getting my customers to understand the suitability, or (often) otherwise, of the artwork that they give me to replicate. We are often sent tiny bitmap pictures of less than 100 x 100 pixels that are taken from the customer’s website and asked to use them on a football shirt or, even worse, a large advertising board.
If we have a bitmap graphic which is 800 pixels by 600 pixels for example, at a comfortable resolution of 200 ppi (pixels per inch), this would mean that the image is suitable at a maximum size of 4″ x 3″, which is hardly adequate for going on to a t-shirt, let alone an 8 ft x 4 ft sign at a football ground. If we were to knock down the resolution to 100 ppi (where we start to see the image as a mosaic), this will still only take us to 8″ x 6″, which is possibly alright for a stagger t-shirt, but not a serious solution to advertising your company.
There are many ways over this problem, one of which, and often the best in the case of logos, is use of the vector graphic, which I shall be discussing here.
What is a vector graphic?
Unlike a bitmap, which is basically a large grid of coloured dots, a vector graphic can be thought of as a set of points joined together and then ‘coloured in’, much like the old painting-by-numbers kits that I recall from my youth. These can be scaled to any size at all without losing resolution or clarity. One way of telling if you have a vector graphic is to zoom in as far as you can to a place where two colours meet. If you see a mosaic of squares, you have a bit map; if you see sharp lines, chances are that you have a vector.
Are there other ways of telling a bitmap from a vector?
If your graphic is either a .jpg, .jpeg, .gif or .png file, then it is definitely a bit map file. If the graphic is an .svg, .pdf, .cdr, .ai or .eps file, then it might be a vector. Unfortunately, all vector graphic programs allow bitmaps to be embedded in their files, so just because your logo is called mylogo.eps it does not mean that it is 100% vector.
Vector graphic programs cost a lot of money don’t they?
Most people seem to think that vector graphics packages cost the earth and they therefore see no point in buying them to use once or twice to make a company logo for themselves. I can understand this. At least, I would be able to if it were true.
Inkscape is vector graphics software that runs on almost any operating system (it works best in Linux distributions, but I have used both Mac OS and even Windows versions) and, like nearly all Linux software, is open source and absolutely free. (If you would like to try out Inkscape for yourself, there is a link to the download at the bottom of this page).
Are there any other advantages of using vectors?
The great thing about vector graphics is that it is so easy to change the colour of any or all parts of an image. This means that a full colour logo can quickly be made into a version which is suitable for pad printing onto a pen, or cutting in vinyl to go onto a vehicle, or for being made into an embroidery.
Illustrated examples please!!
For this section, I have kindly been given permission by one of our customers, Kettlebells Aberdeen, to use their logo to illustrate my point.
Using Inkscape, I redrew the logo and produced this - Kettlebells logo – vector. (follow the link to download the pdf file). You will see that you can zoom in as far as your viewer will allow, and there is no jagged edge to be found. There is still some work to be done on this, such as rounding corners and aligning the bottom edge, but I hope that it adequately illustrates the points made.
To further illustrate the point about the ease of changing the colours, I produced a ‘flat’ or 2D version by restricting the number of colours to 3. This can now be used as an embroidery, or put on to the side of a van using vinyl. Flat KB Logo 3 colours (follow the link to download the pdf vesion). If a single colour version is required for, say, putting on to the side of a pen, we simply change to grey and red sections in a couple of clicks. If we want to use a black background, we can simply change the black to white, or some other colour as required.
I hope that this has given you an insight into the usefulness of vector graphics for logos. Please beware, however, that it is horses for courses, and vectors are not, and should not be used for photos. If you try this, it will make all your photos looked like they have been ‘painted-by-numbers’ as I said at the start of this posting. More vectors stuff to follow in the near future.