Images were collected for each of the identified categories using manual keyword searches in standard image search engines, from IP addresses in the United States and Hong Kong. Images were collected in the time period between September 2017 and October 2020. Since reachspace categories do not generally have specific names, the most effective search strategy for locating a given reachspace type was to append an activity name to the name of the furniture item that supports it (e.g., “crafting desk,” “illustrator's desk,” “work desk”). To find images depicting the whole reachable environment, with correct camera angle and framing, the following strategies were adopted: appending the first-person “my” to the search term (e.g., “my crafting desk”), adding adjectives such as “cluttered” or “organized” to the beginning, and appending “setup,” “layout,” or “display” to the end. To increase cultural diversity in the image set, we conducted searches on Baidu and Yahoo Japan in addition to Google and Bing, and used English, Chinese, and French search terms. Additionally, some reachspace images were original photographs taken by the experimenters. Finally, images were also found using the “Similar Image” features provided by many search engines.
All images in the database are real-world photographs (not CGI), saved in a jpeg format, and are in full color. Images were included if they met the following quality control criteria: (a) The image resolution is equal to or larger than 125 × 125 pixels (mean: 1,137 × 846); (b) the image depicts a view similar to what an observer would experience if they are standing or sitting in the space, actively engaging with it (depicted space is between approximately 2 and 4 feet in depth, camera position approximates an ecological viewing angle); and (c) the center of the space, where the bulk of the hand–object interactions takes place, is approximately centered in the image frame. Images were excluded if they contained clear views of people, hands, or faces; if they contained a large watermark (small watermarks on the edges of images were allowed); if they had clear filter effects; or if they depicted contrived layouts, such as those in staged advertising images. Images were occasionally cropped to better fit these criteria.