Cast - Transmissometer deck test voltage range 
Cast voltage0       dark        100%(in air)
030 # span 8 =     0.0562,     4.8217
053 # span 8 =     0.0562,     4.8254
069 # span 8 =     0.0562,     4.8266

Using Min & Max for M calc: 0.0562  4.8266
