The GlueX experiment's electromagnetic barrel calorimeter should detect photons as low as 40~MeV and as high as 2~GeV.
Moreover, the amount of light produced in its scintillating fibers should be as high as possible for a photon of a given energy, while preserving an adequate number of radiation lengths.
To this end, Monte Carlo studies have been carried out and show that modest gains in threshold and light collection can be delivered, using 0.3~mm lead sheets instead of the nominal 0.5~mm sheets. Results on energy resolution, fractional energy deposition, as well as shower profile development and energy leakage are shown.
