This preliminary study explored the relationship between imagery vividness before and during a hypnotic phenomenological assessment procedure, the Phenomenology of Consciousness Inventory-Hypnotic Assessment Procedure (PCI-HAP), while also assessing trance (hypnoidal) state effects and several other variables. The PCI-HAP allows the assessment of trance state effects associated with hypnotism to be quantified and statistically assessed. The 102 subjects completed the PCI-HAP along with several other questionnaire items. Correlational and regression analyses suggested that imagery vividness during hypnotism (hypnotic imagoic suggestibility) was predicted by combined imagery vividness before hypnotism and trance (altered) state effects during hypnotism. When measuring several additional variables, imagery vividness during hypnotism was found to be a function of self-reported hypnotic depth and additional other variables. The usefulness of these results for better understanding imagery vividness before and during hypnotism is discussed.