Why does my artwork look blurry?

When customers bring their own artwork to our busy art studio, one of the most common things they'll ask is 'why does my artwork look blurry?' Well, it’s all down to the type of artwork they've supplied. In a nutshell, there are two types of artwork file, and using the right one for the right project will ensure you get the best results from your print supplier every time.

So, let’s go through the two types of artwork:

1. Raster Artwork

Raster (also called ‘bitmap’) artwork is pixel based, usually it’s a photograph or an image captured by a scanner. Raster images are very good at displaying graduated colours or tints. The millions of tiny pixels that make up the image can each be a slightly different colour, meaning that colour blends can look really rich and smooth.

However, there is always a resolution to raster images, meaning the more you enlarge it, the more pixelated the image will look. So, it’s important to make sure your image resolution is high enough to prevent the printed version from looking grainy or blotchy. Although low resolution images are ideal for websites, when it comes to print, you’ll need a high resolution image. 300dpi is the recommended minimum resolution for print. So, if you’re scanning a photograph to be printed, make sure your scanner’s resolution is set to 300dpi or higher.

The most common file types for raster images are JPEG, PNG, Gif or Tiff files.

Tip: Try saving your raster images as ’PNG’ files in preference to JPEG. Whilst they are a bigger file size than the JPEG option, PNG files are very good at maintaining detail and displaying graduated tints at their best.

Tip: The higher the resolution, the bigger the file size will be, so choose a happy medium between a file that’s a high enough resolution to print well, but not too huge a file size to be a burden on your server space! As a rule of thumb, I’ll always use images with a resolution of 600dpi, unless it’ll end up being a massive file size.

2. Vector Artwork

Vector artwork doesn’t have a resolution! It works by computer software mapping lines or curves between a set of fixed points on a grid. Flat blocks of colour are mapped in between the lines or points. Those points are always in the same position in relation to each other, so no matter how much you enlarge the artwork, whether your design is the size of a postage stamp or the size of a skyscraper, it always remains razor sharp.

Vector artwork is commonly used for engraving, stencils, and silk-screen printing, where there needs to be a clearly defined path between image and non-image areas. You’ll commonly find vector artwork used for designing logos, digital illustration or for ‘spot colour’ printing. Fonts are also vector files.

Tip: Always draw logos in vector software such as Abode Illustrator or Vecteezy if you can. Just imagine if that wonderful logo you designed for a simple business card ends up becoming a successful brand? You’ll need a bigger version of it to print on a large sign or the side of a van! Scaling it up or down makes no difference to the file size. Whilst vector artwork can easily be turned into a raster version, it’s not so easy to convert from raster to vector.

Because vector artwork is made of points rather than millions of pixels, the files are generally much smaller than their raster counterparts. The most common vector file types are AI (Abode Illustrator), EPS and SVG.

Advantages of raster artwork:

• Capable of smooth, rich colour blends

• Ideal for photographs or scanned documents

Disadvantages of raster artwork

• Large file size

• Constrained by resolution

• Will get progressively worse in quality the more the image is enlarged

• Difficult to convert to vector

Advantages of vector artwork:

• Infinitely scalable without losing sharpness

• Small file size

• Best for solid colours

• Ideal for illustrations and logos

• Vector files can easily be converted to raster

Disadvantages of vector artwork:

• Difficult to blend colours without rasterising

Funnily enough, you can actually have a mixture of both vector and raster elements in the same piece of artwork. ‘Vector with raster effects’ is commonplace for vector logos which have colour blending or tints within them. File types such as PDF and EPS will often contain elements of both, particularly if you have photographs and text on the same page.

By preparing the right kind of artwork for your printed job, you can be assured of the results you're expecting every time. If in doubt, check with your print supplier. What will you be getting printed next?