These Step-by-Step Instructions guide you through the Sketch Map Tool and provide useful recommendations.
You can download and print this manual if needed.

Answers to the Frequently Asked Questions can be found in the FAQ section below.

Learn more about the combination of the Sketch Map Tool with additional data collection methods in the Additional Information section.

As the current version of the Sketch Map Tool has only been released very recently, problems might still occur during different steps of the process. We are sorry if this causes any inconvenience for you! We strive to continuously improve the product, so kindly inform us about the technical issues via GitHub Issues.

Step-by-Step Instructions

Create paper maps to collect data

1.1 Define your Area of Interest

Select your area of interest either by zooming into the map preview or with the search function in the sidebar.

Choose from different paper formats and a suitable page orientation. The dashed red line represents the boundaries of your area of interest, which will be printed on the Sketch Map.

Recommendations:

Adapt the extent of your selected area to your use case. The following questions should be kept in mind:
- What should be mapped by the participants?
- What should be visible on the map and in what level of detail?
- Which areas should the map cover?
Adapt the area extent to the paper size you want to use.
The area is too big? Create multiple Sketch Maps.
Aspects you might want to consider for the selection of the area of interest:
- Ensure orientation on the map: streets (and their names) and some landmarks should be visible. Besides visual inspection you can check the landmark density result in the quality report.
- Cover all relevant areas for your use case: e.g. if studying flooding, cover especially those areas near rivers, creeks and sinkholes as well as critical infrastructure which might be affected by the flood event.

1.2 Map Quality Check

The generated Sketch Map uses a base map layer of OpenStreetMap (OSM). The Map Quality Check helps to evaluate the OpenStreetMap data fitness of the area of interest for the purpose of participatory mapping based on a quality analysis of the OpenStreetMap data with the HeiGIT ohsome quality analyst (OQT). The fitness report can be downloaded as PDF file by clicking on the blue button. It includes an evaluation of the suitability of the local OSM data and recommendations for the subsequent field data collection.

Recommendations:

Before you use OSM based maps of your area of interest for participatory mapping, please have a look at the results of the Map Quality Check to ensure that participants can orientate properly on the paper maps.
The analyses are focused on the landmark density, the up-to-dateness of amenities and streets, as well as the saturation of amenity and the road network mapping. You can learn more about the analyses and each indicator in the generated PDF report.
The report includes useful recommendations to ensure that the generated maps are suitable for participatory mapping.
In case the OSM data of your area of interest is not sufficient for the purpose of participatory mapping, you can consult the Missing Maps project to improve the OSM data before using the Sketch Map Tool. For example, you could conduct a mapathon.

1.3 Export Sketch Map as PDF

The generated Sketch Map for your selected area of interest can be downloaded as PDF file by clicking on the blue button.

THEN: Data collection in the field

At the moment the Sketch Map Tool detects red, blue, green, yellow, turquoise and pink markings. Red and blue markings work best in most cases. The detection works best if the marked areas are filled out entirely.
Please make sure not to accidentally mark the globes on the edge as they are needed to improve the automatic map detection.

Recommendations:

Use thick felt-tip pens with intense colours.
If you have many participants or you want participants to provide a lot of different information, it is recommended to use individual Sketch Maps for each purpose/topic or per participant.
Prepare the same set of pens for all participants/groups for better comparison of the results.
Inform all participants that markings should be filled out entirely and should not cover the globes on the edge of the maps.
If different colours are used for specific topics it is possible to let participants include a legend for the meaning of each colour outside the map extent. However, the tool currently does not use this information. This needs to be done manually in the subsequent analysis process in your Geographic Information System software.
If you collect additional information from the participants with other data collection methods such as Kobo Collect or ODK, add a number on the Sketch Map and save this number in the data collection questionnaire.

Paper to GIS: Automatically digitize collected data

2.1 Scan or photograph your marked Sketch Maps

After the field data collection, scan or photograph the marked Sketch Maps. The colour detection works best when scanning the Sketch Maps. When taking a picture instead, make sure that the QR-Code is complete and that all globes are visible on the image. The scans or photographs must be in jpg or png file format for the upload to work.

Recommendations:

If you cannot scan, the photos must be taken from above in a 180-degree angle (parallel above the Sketch Maps) to produce the best possible result.
Please upload a complete image of the Sketch Maps and do not try to cut out the map from the photo.
Take care of the lighting conditions when taking a picture.
The georeferencing works best if you scan the marked Sketch Maps with a resolution of 300 dpi. Attention! The file size will be too large when scanning with a 600 dpi resolution.

2.2 Upload your Sketch Maps

To upload files you can click on the upload field or drag and drop your files directly in the upload field and then click on the Upload button. You can upload one or more marked Sketch Maps at once. The upload works for jpg or png files.

Recommendations:

It is possible to upload more than one Sketch Map at the same time, but the upload will take longer.
If you are experiencing problems during the upload process, please check out the FAQ section below.

2.3 Download collected Markings as Geodata

You can download the georeferenced Sketch Maps as GeoTIFFs (zip) and the colour-detected markings as vector data in a GeoJSON file.

The GeoTIFF raster data output files consist of georeferenced images for each of your uploaded Sketch Maps.
The GeoJSON vector data output file contains polygons for the markings of each uploaded Sketch Map. Each polygon has attributes about its colour and its source filename (from the uploaded image).

Recommendations:

If you are experiencing problems during the upload process, please check out the FAQ section below.

FINALLY: Import Geodata in a GIS, e.g. QGIS

You can load the vector data file into your GIS software. The layers have different attributes (check attribute table) which correspond to the different colours and file names of the uploads. You can also open the GeoTIFF file for validating the colour-detection of the markings. The GeoTIFF output files consist of georeferenced images for each of your uploaded Sketch Maps.

When you open the files in QGIS, it should look similar to this example and show all the markings of your Sketch Map(s).

Recommendations:

In case some of the sketches have not been digitized correctly, you can use the GeoTIFF file to manually create/adjust the polygon layers.
If the imported data looks strange and does not represent the actual markings of the sketch maps, please check your uploaded sketch map files and if necessary, scan them again or take new pictures according to the recommendations above. Please review the recommendations in the sections about the data collection, the scan or photograph and the upload above and consult our FAQ section about the problems in the colour detection.

FAQs

What are OSM data?

OpenStreetMap data are freely accessible geodata. You can find out more about it here.

What are the quality levels for OSM data used in the tool?

The OSM data are classified with a traffic light system. Green stands for good suitability of the data, yellow for possible problems when carrying out a Sketch Maps study with OSM based Sketch Maps, and red for probable problems. Recommendations are also given on what to consider based on the results.

Which analyses are performed and why?

You can read more about the analyses included in the Sketch Map Tool in this paper.

Why is it important to analyse the suitability of OSM data before creating a Sketch Map?

OSM data are used for the creation of the Sketch Maps. If the OSM data in a study area are lacking some important features, they are missing on the maps as well. Thus, the quality of the OSM data is directly related to the quality of the Sketch Maps. The features might be relevant for participants to orientate on the map.

For which research questions can the Sketch Map Tool be used?

The Sketch Map Tool has been primarily developed for research questions related to floodings. But as the quality indicators used like the density of landmarks, currentness of the data and data completeness are also important in other use cases, you can also use it to investigate a completely different research question, as long as you check that it fits your purpose.

How does mapping work with the Sketch Map Tool?

The local population can for example draw flooded areas such as streets, parks, etc. on the printed Sketch Maps. The larger paper formats also allow to hold group discussions about flooded areas. The maps with the markings can be photographed and uploaded to the tool. The georeferenced TIFF and vector files can then be further analysed or used.

How large can my study area be?

So far the Sketch Map Tool has only been tested on neighbourhood or city level. The max. size of the study area is limited by the selection tool.

Why are there a QR code and globes on the Sketch Maps?

The QR code is required for georeferencing. The globes support the detection of the map in your uploaded images. This is why it is important to have them on the Sketch Maps.

Can I access my results at a later point of time?

No, the results should always be downloaded directly after using the tool. If you forgot to download the files, you can simply upload and process the files again.

What do I have to pay attention to in the field?

Please make sure you do not accidentally mark the globes at the edge as they are needed to improve the automatic map detection. But if someone accidentally marked the globes, it is still possible to upload the Sketch Maps. Use thicker felt tip pens with intense colours. Red and blue markings are best detected in most cases. Prepare the same set of pens for all interviewers. Add a number on the Sketch Maps and save this number in the questionnaire as well, if you use one. An overview of each step with recommendations can be found here.

How does the georeferencing work?

You can find your answer in the paper about the Sketch Map Tool in the paragraph about 'Image Processing'.

What do I have to consider when photographing the Sketch Maps to get the best possible results?

The images need to be in .jpg or .png format. All files together may not be larger than 500 MB. The georeferencing works best if you scan the marked Sketch Maps with a resolution of 300 dpi. The photos must be taken from above in a 180-degree angle (parallel above the Sketch Maps) to produce the best result. An overview of each step with recommendations can be found here.

How do I check if the georeferencing is correct?

You can open the TIFF file in a geographic information system (GIS), such as ArcGIS or QGIS, to check this. If you load the file there and insert a basemap (for example the OSM basemap) you can see if the georeferencing has worked. The Sketch Maps should match the base map.

Why does my generated TIFF file look strange?

Please first try to open the file in a geographic information system (GIS) such as ArcGIS or QGIS. The georeferencing may have worked even if the TIFF file does not look right. If it is still incorrect in the GIS, the map could not be properly detected by the tool on the photo for which there are various possible reasons. For example, the photo may have been taken from the wrong angle or the globes may have been painted over.

Additional Information

In this section, we will shortly provide more details about how the Sketch Map Tool can be combined with additional data collection methods. Stay tuned!