If you don’t know the difference between vector and bitmap files, this is a good reason to find out. Here’s my explanation: If you take a picture (in the form of .jpg, .gif, .png, etc.) and increase it’s size, you’ll notice that the quality of the picture gets worse. That’s because if the picture is made up of 100 pixels, by increasing the size of the picture (which is saved in a bitmap form) you are effectively increasing the size of each pixel, hence making the tiny little buggers more visible to the eye. The result is a more grainy look which is characteristic of low quality pictures.
When you buy a digital camera and the salesperson says this one is 2 megapixels or 6 or whatever, that’s what they are referring to: The number of pixels that will be captured by the camera’s digital processor and hence the number of pixels that will be printed on the paper. The more pixels you have the better it is for printing larger size photographs. This doesn’t mean that a 10MP camera will print a better picture than a 2MP if they are both printing on 4×6 paper. You can still only see 72 dots per inch (or dpi) on your screen, and when you print you can still only fit so many pixels in a given area. So as a side note to this week’s post, if you are thinking of buying a digital camera and if you are not planning on printing on anything larger than 8X10, a 3.2 MP camera will do just fine.
Now back to the topic. Unlike bitmap, a vector graphic is one that uses mathematics in order to calculate its shape. For instance if I am using software such as Adobe Illustrator to draw a line which may contain 100 pixels, and then I extend the line by dragging one of its corners, then I am sending a signal to the computer that I want the line to increase in size and the computer then adds pixels to fill the space. So if I double the size of the line, it should now have 200 pixels as opposed to 100 pixels that are twice the size. So vector files = quality is untouched and bitmap files = don’t mess with the size!
To draw our directions card for our wedding venue, I wanted to trace a Google Map image in order to keep the proportions correct. I started by placing the image below into Keynote (Apple’s equivalent to Power Point but 1,000,000 times better – no bias here).
You can do this by using a screen capture tool, pressing the “Print Screen” button on your PC, or Shift+Command+4 on a Mac and selecting the area you want to capture.
I then traced the route using a line drawing tool. You will find this under “Shapes” in Keynote. What this allows you to do is to click along the line of the road while a line joins the point you are on with the previous one. The more clicks the smoother the line. This being a graphic tool, the line is a vector file so there’s no degradation to the quality of the image if it is resized later.
Below is a picture of the tracing process. Don’t worry about making mistakes. You can always click on a a single point along the line and either move it or delete it.
Once I had the lines traced I played with the sizing of the stroke to emphasize the highway. To do that, you first select the line you want and then from the Graphics Inspector you change the stroke of the line. Although in the picture below I used two thicker lines to emphasize the highway, you will see later on that I then changed to a single line of stroke thickness 23px for the highway and 6px for the side roads.
I then added some directional arrows and text, again from the “Shapes” menu, and removed the now traced satellite image by moving it out of the way. A couple of more details included a blow-up of the traffic circle close to the hotel, and some labels to indicate the road names, etc.
Then I selected each item and from the Graphic Inspector I changed the colour as shown below. To make the filled area representing the Mediterranean Sea, I used the line art tool again but this time I added three more points to connect the 90 degree triangle that takes up the bottom left corner of the map. You’ll see that by connecting the first point of your line to the last one, you end up with an area filled shape.
A quick copy and paste into Adobe Illustrator and my job is done. The beauty of using Keynote was its simplicity. Once in Illustrator I could resize up or down with no loss in quality.
I hope you’ve found this useful. What programs do you use for your design work?
Until next Friday, this is Mr. Milk signing off.