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Rather
Rather
Examples of the color constancy illusion, adapted from Akiyoshi Kitaoka's 'Eye color constancy illusion 2019'

All eyes have the same color

This type of illusion became widely recognized through a viral social media image dubbed "The Dress" and related work by the Japanese professor Akiyoshi Kitaoka.

The following test quantifies how strong this type of illusion is for you personally.

Promised – it's a fun and brief (5min) test!

  1. Your task is to match the color and brightness between the two eyes by using the color wheel.
  2. Report the color you subjectively perceive, not the color you think makes sense.
 
This information is optional: fill us in to support science.
Age (years):
Gender:
Country of birth:
Country of residence:
Color vision:
Ambient light:
(under which you performed the test)
Your device:
Screen brightness of your device:
(how you would describe it)
I made a serious attempt at this test: No Mostly Yes

Terms

The test is completely voluntary. You can stop the test at any time.

What kind of data will be saved? The test will save your perceptual responses and (if provided) demographic information about your age, gender country of birth and color vision. In addition, some basic technical information provided by you (e.g. ambient light conditions) or the browser (e.g. screen resolution) is stored. No identifying information is inquired or stored (e.g. IP address, name, address).

What will be done with the data? The data is saved on a server of the Health and Medical University Potsdam. It might be publicly shared at a later point and/or used in scientific publications.

Can I withdraw my consent and request the deletion of data? Yes, please use the contact information below. However, in the spirit of open science, the data might be publicly shared at some point. Following this, deletion of the data is no longer possible.

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Who is responsible for this test? Prof. Matthias Guggenmos, Health and Medical University Potsdam, Olympischer Weg 1, 14471 Potsdam.

Contact: matthias.guggenmos@hmu-potsdam.de

Use this email address for any questions about the test.

Online tests come with many challenges and accuracy is definitely an issue. One important step to address this, is to measure what scientists refer to as test-retest reliability. That is, to what degree do your results match between two repetitions of this task?

If you're interested in this, or if you just want to help us measure test-retest reliability, you can now repeat the task.

Important: only proceed if you're the one who did the task just now. If you want to start the for a different user, please use the browser reload button instead.