We have conducted preliminary time-resolved solution scattering studies on the morphological change of bacteriophage HK97 from Prohead II capsid to Head I capsid, one of the most significant maturation processes of this icosahedral phage. After some trial measurements, we discovered that lowering pH from 8.3 to 4.0 effectively transforms Prohead II to an expanded morphology similar to Head I. Further studies were made during the beam time assigned to the letter of intent submitted by J.E. Johnson later in the year.