As the cost of printing images professionally can mount up, more and more photographers invest in their own high quality printers at home. What’s required is a good machine, paper, inks and a computer. However, the quality of what you see and what you get at the end is not always the same thing. Understanding the basics of printing your images will help you get the result you want without wasting too many consumables.
What is Printer Resolution?
Printer resolution refers to the numbers of ink dots per inch (dpi) that emerge on the paper while printing an image. These dots are formed and measured horizontally and vertically (i.e. 2800x1400 dpi). Most inkjet printers have a resolution of 1200 dpi while the more advanced models can produce up to 9600 dpi. Having more dots per inch produces finer details, resulting in sharper text and clearer color images. There is a preferred dpi rating to obtain minimum resolution for certain tasks. For example, text and graphics for “general-purpose”, require 300 dpi while higher quality graphics require 600 dpi. But, the dpi rating for photo-quality images is around 1200 dpi and for professional-quality images it stands around 2400 dpi.
As you can see from the example images above, there is a marked difference in image quality that is directly dependent upon the printer’s resolution. Higher resolution enables sharper, more detailed images to be produced, thus improving the overall quality of the print.
DPI (Dots Per Inch)
As mentioned before, the higher the dpi, the higher the quality of the finished printed photograph (and the more ink you will use!). DPI refers to the finished print, and how many dots of ink have physically been imprinted onto that piece of paper. If you inspect a print out afterwards, you will be able to see if the color is vibrant, if the edges are sharp or blurry etc.
PPI (Pixel Per Inch)
Pixels per inch, refers to the resolution of the digital image - that is, the image you see on screen on your computer. When you enlarge any digital image, eventually you will see square blocks which are pixels. These pixels create an image, though pixels won’t be apparent when the image is printed. Usually, choosing a higher mega pixel count on your camera will give a high PPI count and generally a finer image.
Why does my Printout Look Blurry?
If you print a small image in a large size, the pixels in your image will have to stretch to fill the print area, resulting in a blurred image. Remember, the basic quality of an image can be improved only when there are more pixels in the image. When you try to enlarge an image beyond a reasonable extent, the pixels get bigger and more visible. A high dpi printer setting makes each pixel look more distinct, and thus the resultant image looks completely ruined. So, if you want to produce sharp and good quality prints, your image must hold a large number of pixels close to one another. If your printout still looks blurry, you need to consider a few points. Did you shoot the image with at least 10 megapixels? Choosing a low quality format may save space but gives you less pixels in the image to start with. The more you enlarge an image the more apparent blur and pixels will be, so be aware that a 100kb image will never translate well into a 8x10 print.
Printout Guide
Make the conscious choice when you are shooting to choose a higher megapixel setting if you know you will want a large photograph from it later (i.e. weddings or travel images). A 2 megapixel image, for example, has a resolution of 1600x1200 and can print to around a 4x6 image. Any larger and pixels will very likely appear. However shooting at 12 megapixels means you have the choice to print up to a large 21.4 x 14 inch image or much smaller if you prefer. If in doubt, do a small test print (choose the draft setting) and see what the results are.
Printer Settings
High-end home photo printers will tend to come with some other settings you may want to experiment with. Dithering, for example will create scatter dots which means a printer with only a few color cartridges will try to make up the color you require using a blend of these. Advanced printers normally require a minimum or three colors plus one black, but this can go up to 8 or 9 separate color cartridges. Remember to perform regular print-head cleaning; otherwise the heads can clog up.
Conclusion
Printing photographs at home in the long run will save you money, especially if you are a freelancer. Remember to choose a printer that will serve your purposes. It should have a good dpi rating and can take up to A3 sheets (if you need this). Consider the amount of ink it uses because replacing ink cartridges is costly. Always shoot an image on the highest resolution you can so you get the finest quality print possible. If in doubt always do a rough printout first, followed by the full print. Experiment and soon you will be able to produce laboratory quality images!
