"The implementation and characterization of a pump-probe transient absorption apparatus is presented. Secondly, a comparative study focused specially on transient absorption is performed for two organic macrocycles: porphyrins and novel carbo-benzenes. Absorption and emission data shows that both macrocycles exhibit similar behavior; however, transient absorption data demonstrates that excited state dynamics between the two is contrasting. These investigations contribute to the understanding of excited states in novel carbo-benzenes and demonstrate the successful implementation of a pump-probe apparatus which achieved temporal resolution and sensitivity similar to commercial equipment."