"This was the first film of Oskar's work which was worked on by someone else, in this case, his brother Hans. The basic designs for forms and movements were all [made] by Oskar, and Hans was assigned to complete the sequences, filling in the shadings on the outlined shapes as an apprentice, learning exercise.

"The images in STUDY NO. 9 are synchronized with Brahms' 'Hungarian Dance No. 6,' probably in response to the success of STUDY NO. 7. The graceful figures perform charming choreography which makes STUDY NO. 9 one of the most pleasing of the series. The most memorable moment is a sequence in which dots and rays bounce off a semi-circle, flickering and dividing in conscious interplay with their own after-images, a further extension into pure optics of Fischinger's ideas about atom-splitting." - Dr. William Moritz, Film Culture