Kalmus collaborated with the art and wardrobe departments of motion-picture studios during the preparation and filming of Technicolor productions.

She reviewed their costume selections, set furnishings, and lighting and then specified needed color changes and equipment adjustments to create the best visual "palette" for her company's Technicolor cameras.

[4] In summarizing her duties as the company's color art director at various studios, Kalmus described her role "'as playing ringmaster to the rainbow'".

[5] Those duties also required her to work closely with principal cast during production to establish the best visual environment and emotional atmosphere to support and even enhance the actors' performances.

[6] When presented individually or in concert, those vibrations, according to Kalmus's extensive film experience, can evoke a predictable range of emotional responses from viewers.

If we are not going to go in for lovely combinations of set and costume and really take advantage of the full variety of colors available to us, we might just as well have made the picture in black and white.

It would be a sad thing indeed if a great artist had all violent colors taken off his palette for fear that he would use them so clashingly as to make a beautiful painting impossible.

[10][11][12] The correspondence and records relating to that and other business ventures, along with Kalmus's personal papers are preserved in the Margaret Herrick Library at the Academy of Motion Picture Arts and Sciences in Beverly Hills, California.

[citation needed] The couple "secretly" divorced June 22, 1922, but they continued to live in "separate adjoining apartments" in Hollywood into the 1940s.

[14][15] Despite their divorce, Natalie and Herbert continued to work together for over two decades, with most of their friends completely unaware that their marriage had ended.