Stimulus guidelines

Last updated on 

Space usage

For single images, there is no need to add padding. Use the original image to fill the entire space.

In this example, the black background is not necessary.

If you want to have a background, make sure that the image itself is centered.

If your images contains multiple smaller images, spread them evenly across the available space. You don’t have to keep distance from the edge.

The images are not spread evenly and an unncessecary border is present.

Also, make sure that the text used is in high contrast to the background.

In this example, white text would have been better.

Technical

File formats

For images we recommend using PNG for screenshots and JPEG for photographs. Try to avoid uploading you material in PDF or Word format as they might not be displayed correctly. Instead convert it to PNG or JPEG first.

For videos we recommend MP4, WebM, or MKV files. The frame rate should be between 24 and 30 fps.

Resolution

The resolution of your image should be at least 1270 by 720 pixels. For best results we recommend 1920 by 1080. Try to avoid extremely small images as scaling the images up will cause excessive blurring. Also do not use extremely large images as this might cause long loading times for your participants.

The aspect ratio should be 16:9 because of its widespread use. If material is provided in another ratio, white bars might be used as padding.