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Complex images and Long descriptions can seem overwhelming at first, but if you follow the advice in this section they will become easier.
We create longer, complex descriptions for any image that contains complex information or data. Common examples are Maps, Graphs, Charts and Diagrams. We can also create longer, complex descriptions when we need to transcribe an Image with Text, such as an image of a letter. If you are not sure if your image requires a complex description, ask in the Q&A section.
A complex image
is any image that contains complex information or data. Common examples are Maps, Graphs, and Charts. All complex images require extended descriptions beyond the Alt-text, also known as Long Descriptions.
A Long Description
is a detailed text description of an image that can be several paragraphs long and/or may contain other elements such as tables and lists.
When creating a complex description work from the general to the specific: provide an overview of the image before you describe specific details. The way you introduce a complex image can vary depending on the type of image. We included documentation for all the most common images we come across at the end of this page.
The complex descriptions must also follow the standard Alt-text guidelines (though it will be longer than 2-3 sentences).
A strategy we use is to break the image up into its component parts, and then organize them so that the description makes logical sense.
There are a couple of techniques you can use to breakdown a complex description:
Quadrants
: divide the image into 4 quadrants. Top and bottom, left and right.Compass
: divide the image by North-South-East-West. This is most commonly used for Maps.Clock
: divide the image by the times of a clock. This is most commonly used for images that have the main focus in the center of the image.The type of breakdown will depend on the context, audience, and type of image. Sometimes you will have to experiment with which one works the best for your complex description. By breaking down a complex image into sections you can take the reader on a journey. Remember, you need to be able to walk your reader through the image in a logical order, and you need to be able to recreate the image without looking at it. Using this approach helps to create an immersive experience for the reader. Editing will be important with complex images, go to Editing Alt-text for more information.
A good rule to follow is that all tables need a header row and are used for tabular data. If that fits the image you are describing then use a table. Go to Tables for more info.
If you are using lists, you can also use a more narrative style with the list by adding relational information to the data in the lists.
For images that require more complex or extended descriptions we create two descriptions:
See the link below the image for an extended description.
at the end of the description
Remember to include a basic Alt-text description for the image itself along with a note that the reader can find a longer description in another location of the book. Simply enter the sentence See the link below the image for an extended description.
at the end of the Alt-text. This way readers are aware there is a longer description.
We also do this because all non-decorative images require Alt-text, even if a long description is also provided. Empty Alt-tags in non-decorative images can be confusing to the reader, and leave out part of the experience of reading.
Below is a video that shows how a screenreader interacts with a long description:
When creating a complex description work from the general to the specific: provide an overview of the image before you describe specific details. A good strategy is to break the image up into its component parts, and then organize them so that the description makes logical sense.
This is the most common complex image you will come across in your work. Again, context will also help you out a lot in your description. Below are the general guidelines for how to describe a map.
Spatial relationships are very important in maps. The reader needs to know where they are and where they are going within the description. The most common way to break down a map is with the compass technique, but this also is dependent on context. If you have a map that has a central focus, then the clock technique might be better. You also might find it easier to use the quadrant method. Again, you may have to experiment as you are writing. Remember it has to walk the reader through the image, and be recreated based on the description alone.
See examples on Samples of Alt Text: Maps
More tips on writing text descriptions for maps.
We also recommend checking out the DAISY webinars on the Resources page.
Not all graphs require a long description. More simple graphs and charts can be easily described in 3-4 sentences and can go directly into the Alt-text. When they do need a long description it is important to focus on the facts and data more than any visual elements.
As with maps, ask what is this chart saying? Are there any striking visual trends in this chart? Remember that charts and graphs are used to give visual impact to data, so summarizing that at the beginning of your description is a good idea.
See examples on Samples of Alt-Text:Graphs and Charts: Short Descriptions or Samples of Alt-text: Graphs and Charts Long Descriptions
Again, multiple modalities can be used when necessary. Below are the more common Graphs and Charts you will come across.
Below are the guidelines for describing a Bar Chart.
See examples on Samples of Alt-Text:Graphs and Charts: Short Descriptions or Samples of Alt-text: Graphs and Charts Long Descriptions
The description for a pie chart needs to reference the following data elements:
See examples on Samples of Alt-Text:Graphs and Charts: Short Descriptions or Samples of Alt-text: Graphs and Charts Long Descriptions
Flowcharts and Trees are all about relationships. Don’t get weighted down on the visuals. Focus on the meaning of symbols and not their appearance. A line could be Yes or No, or it could be a mother or daughter. Describe what it means and not what it looks like.
The description of a flowchart needs to reference the following elements:
For examples, go to Samples of Alt-text: Graphs and Charts Long Descriptions and the Poet Centre has some great examples you can work through as well!
A Venn Diagram consists of a list of elements interacting with each other to form sets. Your description should trace the diagram in a clockwise direction and list each interaction and the sets created by those interactions.
The description of a Venn Diagram needs to reference the following elements
For examples, go to Samples of Alt-text: Graphs and Charts Long Descriptions.
Depending on the context, a painting may need a complex description. These can be especially complicated and overwhelming since art is so subjective, and if it requires a long description then the painting may be very detailed. Like all long descriptions, break it down into logical parts and start describing.
The description of a Painting needs to reference the following elements:
The Poet Centre has a few tutorials on writing Alt-text for paintings that are very helpful.
For a complex description it is important to consider the context for which you need the description. This may include:
For examples, go to Alt-text Samples: Paintings.
Unlike other long descriptions described above, shapes are important to Anatomy and Diagrams with Labels. Spatial relationships are also essential. You do not want to simply list all the labels without context or relations. Remember, you want to walk the reader through the diagram, and you should be able to recreate the image from your description.
The description of an Anatomy Image or Diagram with Labels needs to reference the following elements:
For examples, go to Alt-text Samples: Anatomy and Diagrams with Labels
35 minutes per image
. The average editing time is 25 minutes per image