by Katrin Mehl and Elisabeth Fischer
We often present technical information as text. The more complex the information, the more words we have to use. When we describe a complex engine with dozens of components, plugs, and valves, we sometimes need an additional form of presentation, such as an image. Images, like diagrams and illustrations, give the reader a visual layout of components, devices, or technical parts.
But how can we create a meaningful and descriptive image? Which image resolution and size should we use? Do we need to apply style rules of a corporate guideline? Does our image require a certain perspective and additional description? And how much time and money do we have for creating an image? In this article, we want to address these questions and also point out possible obstacles in image creation.
Before you begin visualizing technical information, consider the following:
- How much will it cost to create the image?
- Color space: Do you need the image in CMYK or/and RGB? For the internet, we usually use RGB.
- Aspect ratio: Do you have to consider a certain aspect ratio for the image, for example, 16:9 or 4:3?
- File format: File format and image resolution depend on the type of publication in which the image will be published. For a website, you will most likely create png or jpg files. A 96-ppi image resolution keeps the loading time of a browser window short. This is important for mobile websites. For a high-quality print, you need at least a 300-dpi resolution.
- Perspective: Do you want to present the image from a different perspective? In CAD programs, you can rotate three-dimensional objects and describe them from another view.
- Will the image stand alone or will you add a description?
- Which is the leading medium, the image or the text? Which important information should be visualized in the image?
- How much time do you have?
- Can you create the image with the given time and money?
- Do you know your audience?
- Do you have to take into account the cultural background of your readers? Do they perhaps read right to left? Could they interpret colors or graphics differently?
- Could some of your readers have impaired vision?
- Do you need to follow rules from a visual style guide? Or do does your customer have a concrete idea that you have to consider?
- Can you use existing images as guidance for a consistent visual representation?
- Do you have to translate text in the image? Some graphic programs support automatic translation.
- Are there legal or normative requirements you have to follow? The following norms might be relevant:
DIN ISO 7000 „Graphical symbols for use on equipment“
DIN EN ISO 780 „Graphical symbols for handling and storage of packages")
DIN EN 80416-1 to 3 „Basic principles for graphical symbols for use on equipment“
Types of Depiction
Once you know the external conditions, you should decide what type of depiction fits your purpose. If you want your readers to quickly locate buttons on a machine or in a graphical user interface, you may need a realistic image. Perhaps a more simplified image would do the job as well. The following paragraphs describe the different depiction types and their purpose:
Concrete or (almost) photo-realistic depiction
This type of depiction comes closest to reality, the most concrete being the photograph. Also, computer graphics, such as 3-D illustrations and animations, are concrete and realistic. We use them when a strong reference to reality helps the reader understand information. Example: A photo of a product showing the different connectors helps the reader identify and locate them.
Stylized depictions are 2-D graphics with 3-D optics, sectional views, line drawings, or pictograms. They have a lower reference to reality but can increase the viewer’s comprehension. We use them to generalize reality. Take a drawing of the parts of an engine. If we use a line drawing instead of a product photograph, we can exactly locate and label the individual components. The line drawing is still so unspecific, however, that we do not have to update it in case of small visual changes.
Abstract depictions are logical images that visualize facts in a way we do not see in reality. They help us understand complex relationships. Compared with concrete and stylized depictions, abstract depictions have almost no reference to reality. They are not created to visualize a real situation but show structures. Take a map of the public transportion network of a big city, the bus network for example. Lines symbolize the bus routes. Instead of showing all the curves or intersections, the map provides a general overview.
Schemes and diagrams are also abstract depictions. Some require prior knowledge from the viewer, for example, diagrams that are written in BPNM (business process model and notation).
The methodological approach
Image creation usually begins with research. You collect information from many different sources, which means that you may end up with a lot of information. Therefore, try to narrow your research by focusing on a particular theme and then select the information accordingly. When you create the image, try to simplify and structure the information that you want to convey. This way, you can better control how the viewer receives the information. Present the most important information in a way that the viewer can quickly grasp and process it.
Important: Each image should consist of a major piece of information und few minor information pieces.1
Research and inspiration
Some graphic tools come with a library of symbols and make life easier for the designer. If you do not have a library, you are literally looking at a white sheet of paper. You can get some inspiration in books, magazines, and, of course, the internet. Take a look at the following websites, for example:
You can also use existing images, even if they will account for only a small part of your new image.
Note: If you use images that you did not create yourself, make sure that you follow copyright law.
Rhetorical figures and abstractions
Rhetorical figures or abstractions2 can also help you to create a first draft of an image.
We know rhetorical figures from literature, metaphors, for example. They make text lively and powerful. We use them also in the visual language. A visual metaphor is based on vivid, figurative language. "The wheels of justice turn slowly." "The computer in the classroom was an old dinosaur."
The metaphor in the visual language is a graphic expression representing a concept or term. Depending on our background and experience, we identify the image and link it to an idea. Think of an image of a garbage can. Seeing that picture, we instantly understand the meaning.
Another way to visualize technical information is abstraction. We create abstract images when we literally cannot grasp the term we want to describe. If the term in the real world does not have a body, we describe or visualize what the body does. The symbol of a Wi-Fi network is a great example. Seeing the symbol, we immediately understand that there is Wi-Fi nearby.
Important: If you want your readers to understand your visual representations, you need to understand their skills and knowledge.
Use rhetorical figures and abstractions with care. They can leave room for interpretations. There is also a risk of misinterpretation. Make sure that you test your images with your audience before you publish them.
Perspective, point of view, and color
Image perspective and point of view need to fit you purpose. Also consider style (2-D or 3-D, line drawing, flat representation, or photo) and color.
If you decide to use a signal color for highlighting, make sure that you do not transport important information only with this color. Many people have limited or even no color vision. In that case, important information can get lost.
If you create the image yourself, keep it as simple as possible. Bells and whistles distract and make the image restless. The human brain recognizes silhouettes, faces, and figures faster than other image contents.
Most of the time, we create icons, logos, and pictograms with a large zoom factor but publish them as small images. Test whether your image is scalable and also check if small details are still recognizable. If not, ask yourself if those details are important. If they are, you have to find another way to include them.
Always create several variants3 of your image and evaluate them. The first idea is not always the best. But you can use that idea to further develop your image. Also, get a second opinion, but narrow down the choice before.
Create a visual style guide
Your final image can serve as a basis for a visual style guide.4 A visual style guide is similar to an editorial style guide, but limited to images. You can determine, for example, that certain motives can only be used with certain external characteristics or points of views. Or you decide that certain colors or additional image elements are used for gaze control. A visual style guide ensures a consistent look and style of all images. It also makes sure that the images created by several technical writers over a long period of time do not alter the overall look of the documentation. The visual style guide and the editorial style guide are part of the style guide of an organization.
Technical writers need to work efficiently. They want to reuse content and also want to easily change the content. For the visual part of technical documentation, you can employ graphic tools to enforce the rules that are set in the visual style guide. At least at the beginning, enforcing the rules this way will be a lot of work. In the end, however, it will pay off.
You can save frequently used images as templates5 in a library. These images are displayed as instances from the master file. That way, you only have to modify the master. The changes are instantly applied to all the instances. You can use a similar approach with colors and other styles, such as the strokes width. In some programs, you apply your saved styles by simply dragging them to an object of the image.
With this knowledge, you are well prepared to enhance existing documents with images or create new documents that visualize technical information right from the beginning. Clarify your overall conditions before you start and select a type of depiction that fits to your needs. Collect, select and structure the information for your depiction in a way so that the information is presented appropriately to the viewer. Use little helpers, such as abstraction and variation, or external sources to create your image. Also consider possible normative requirements. Facilitate your work and enforce a consistent look and style in your documents. Make use of all possibilities in your work environment and share your knowledge, sources, and tools with other technical writers, if possible. That way you will be able to successfully visualize information, no matter whether your image comes with or without a description.
Our presentation on the subject at the annual tekom conference 2015 (switch to full screen):
Prezi images used with permission from Prezi Inc.
(1) Alexander (2007): Kompendium der visuellen Information und Kommunikation, p. 131.
(2) Alexander (2007): Kompendium der visuellen Information und Kommunikation, p. 33-39.
(3) Alexander (2007): Kompendium der visuellen Information und Kommunikation, p. 39.
(4) Alexander (2007): Kompendium der visuellen Information und Kommunikation, p. 42.
(5) Names vary depending on the application.
- Alexander, Kerstin (2007): Kompendium der visuellen Information und Kommunikation
- Galbierz, Martin: International visualisieren. Benutzerinformation für eine weltweit heterogene Leserschaft. In: Technische Dokumentation optimieren. Raabe: Stuttgart 1994 ff., Beitrag D 6.4.
- Mijsenaar, P.; Westendorp, P. (2000): Hier Öffnen. Die Kunst der Gebrauchsanweisung
- DIN ISO 7000:2008-12, Graphical symbols for use on equipment - Index and synopsis (ISO 7000:2004 + ISO 7000 Database:2008 up to ISO 7000-2750)
- DIN EN ISO 780:2016-05, Packaging - Distribution packaging - Graphical symbols for handling and storage of packages (ISO 780:2015); German version EN ISO 780:2015
- DIN EN 80416-1:2009-11, Basic principles for graphical symbols for use on equipment - Part 1: Creation of graphical symbols for registration (IEC 80416-1:2008); German version EN 80416-1:2009
- DIN EN 80416-2:2002-05, Basic principles for graphical symbols for use on equipment - Part 2: Form and use of arrows (ISO 80416-2:2001); German version EN 80416-2:2001
- DIN EN 80416-3:2003-08, Basic principles for graphical symbols for use on equipment - Part 3: Guidelines for the application of graphical symbols (IEC 80416-3:2002); German version EN 80416-3:2002
- ISO 9186 -1:2014-03, Graphical symbols - Test methods - Part 1: Method for testing comprehensibility
- ISO 9186-2:2008-06, Graphical symbols - Test methods - Part 2: Method for testing perceptual quality
- ISO 9186-3:2014-10, Graphical symbols - Test methods - Part 3: Method for testing symbol referent association
Image Types of depiction (clockwise)
- Camera (Kamera) © filipobr - Fotolia.com
- Screenshot image manipulation program: Extract from GIMP manual
- Camera flash (Kamerablitz) © fd-styles - Fotolia.com
- Screenshot network configuration: Taken from Aviligon control center client, p. 7
- Components of a typical laser © designua - Fotolia.com
- Icon computer. Used with permission from Prezi Inc.
- Icon clock. Used with permission from Prezi Inc.
- How a laser works © designua - Fotolia.com
- Router © kingmarron - Fotolia.com
- Netzwerk VLAN WLAN Diagramm Illustration © vschlichting - Fotolia.com
- Metro or subway map design © maximmmmum - Fotolia.com
- Icons diagrams. Used with permission from Prezi Inc.
- UML diagram © parson AG
- © parson AG
Images Overall conditions for image creation, Selecting information, Rhetorical figures, Abstractions, Create visual style guide - planning, Create visual style guide, Consistency
- Prezi images used with permission from Prezi Inc.