Simple Photorealism: Resolution

Let’s talk a little about the resolution of your image. You might, for example, need a high-resolution image for printing on an 8.5 by 11 inch paper. Your computer screen usually displays 72 pixels per inch. So when we create a 640 by 480 pixel image, that ends up being about 8.8 inches by 6.7 inches on the screen.

Printers, however, usually require a much higher resolution. For an image to appear high quality on a printer, you’ll need it to be 300 pixels per inch, or up to 600 pixels per inch for professional printing. For most basic purposes, resolution is the number of pixels per inch. The higher the resolution, the more pixels per inch.

This is where you need to pull out your computer’s built-in calculator. If you want an 8.5 inch by 11 inch image and you want 300 pixels per inch, this will be 2,550 pixels wide and 3,300 pixels tall. That’s 8.5 inches times 300 pixels, and 11 inches times 300 pixels.

Go to the Output pane and change width to 2550 and height to 3300. This will give you a huge, high-resolution image shaped for an 8.5 by 11 inch page.

This image will take a lot longer to render than our other examples. The larger you make the image, the longer it takes to render. This is a fairly simple scene and it has rendered nearly instantly for me at 640 by 480. At 2,550 pixels by 3,300 pixels it took almost a minute to render on my computer. When using rendering software, you will often need to be patient.

You will almost always want to render your test images at smaller sizes, and only do the full-size, high-resolution image when you are ready to wait.