PROFESSIONAL TRI-X 320 Films are high-speed panchromatic films that are a good choice for photographing dimly lighted subjects or fast action, for photographing subjects that require good depth of field and fast shutter speeds, and for extending the distance range for flash pictures. TRI-X 320 Films (320TXP) feature excellent tone gradation and brilliant highlights. They are especially well suited to low-flare interior lighting or flash illumination. They are also useful for portraiture with low-contrast backlighting outdoors.