A 35-item condensed version of Betts' (1909) Questionnaire upon Mental Imagery, measuring the clarity of mental images a person can voluntarily evoke across visual, auditory, tactile, kinaesthetic, gustatory, olfactory, and organic sensory domains.
Sheehan, P. W. (1967). A shortened form of Betts' questionnaire upon mental imagery. Journal of Clinical Psychology, 23(3), 386–389.
Free access to 2023+ psychometric scales at PsychScales