This guide is intended to help SNHU students use basic design principles to creating professional, academic posters. This guide also provides poster templates and instructions for printing posters at the Library Innovation Lab & Makerspace.
The resolution of the digital files you use for visuals (e.g. photographs, images, charts, etc.) should be high enough that they display clearly when your poster is full size.
Visuals - High Resolution vs. Low Resolution Example
In general, the larger an image will be printed, the higher the DPI should be (a minimum 300 DPI is a good rule of thumb). To check an image's DPI, right-click on the image and go to "Properties" > "Details". Scroll down until you see information about the image including the DPI:
Visuals - Checking an Image's DPI
Checking an Image's Quality at Full Size
Even if you find an image with a high DPI, you should still double-check that the image will appear clearly when printed at a larger size. To do this, you can use Photoshop (or other image-editing software; Photoshop is available on the computers in the Innovation Lab & Makerspace). Here are basic directions but for more detailed directions and screenshots, download the file labeled "Checking an Image File for Quality" on the left:
Open the image in Photoshop.
Using a ruler, measure the size of the image on your monitor.
Calculate the percentage increase by dividing the desired dimension by the actual dimension.
In Photoshop go to "Image" > "Image Size".
Take the result from the above calculation (step 3) and multiply it by the height of the image in Photoshop.
Edit the image height to reflect the result of the above calculation. Make sure that the “Constrain Proportions” checkbox is checked.
Zoom your image to 100% size.
The image’s size on the monitor will now show how the image will appear when printed at the actual, larger size. Examine the image to see if it is grainy, inconsistent, etc. – does this quality meet your expectations for high quality image resolution?
If you need to change the size of the image, check out the file to the left called "Sizing an Image to Specific Dimensions" for directions on how to do this.
Finding a High Resolution Image
There are a number of places online where you can download high resolution images online but remember to be careful of copyright restrictions. One great way to search for high resolution images is to use Google's Advanced Image Search:
Enter keywords for the image you are trying to find
Scroll down until you see the "Narrow You Results" area
Open the drop down marked "Image Size" and choose "Large" or an image with high pixels, then click search
In general, the larger an image is, the higher the resolution will be. When looking at the options under Google's "Image Size" drop down, the choices that say "Larger than ## x ##" are referring to the number of pixels on each dimension of the image.
You may also want to consider narrowing down images by "Usage Rights" to help with copyright concerns