input: [Name] b_v [Offset] 9 [Size] 1 [Description] This is the magnitude level in B-V colour. This value refers to one of 256 discrete steps in the magnitude range for the file [Type] 
output: unsigned char
options: i n t
options: u n s i g n e d c h a r
options: u n s i g n e d s h o r t i n t