Thin nitrocellulose membranes (pellicles) are shown to exhibit properties which make them suitable for intracavity tuning elements in high‐energy pulsed dye lasers. Uncoated pellicles of 2‐&mgr;m and 8‐&mgr;m thickness with surface figures of &lgr;/1 are shown to closely approximate the properties of low‐finesse etalons with wide free spectral ranges. Pellicles of 8‐&mgr;m thickness and coated on both surfaces with 50% reflectivity multilayer dielectrics are shown to be effective as spectral narrowing elements with peak transmission greater than 80% and resultant laser linewidths of 0.57 nm full width at half‐maximum (FWHM).