He is believed to have frequented the studio of painter and stained glass designer John La Farge, whose portrait he painted around 1900.

[1] About 1914 to 1915 his work attracted the notice of Washington DC art collector and critic Duncan Phillips, who became his close friend and chief patron.

[2] Tack's portraits and murals were traditional in style, but he also painted mystical semiabstract landscapes and abstract works on spiritual themes.

Time and Timelessness is an example, displaying Tack's style of contrasting the abstract qualities of his work with figurative aspects, in this case clouds.

From 1941 on, Tack maintained a studio in Washington, DC., where he produced portraits of political and military leaders, including Eisenhower and Truman, while he continued to paint his poetic abstractions.