Luminosity Class V

Type  M_V   B-V

"O5" -5.7  -0.33
"O7" -5.2  -0.32
"O9" -4.5  -0.31
"B1" -3.2  -0.26
"B3" -1.6  -0.20
"B5" -1.2  -0.17
"B7" -0.6  -0.13
"B9"  0.6  -0.07
"A1"  1.0   0.01
"A3"  1.5   0.08
"A5"  1.9   0.15
"A7"  2.2   0.20
"A8"  2.4   0.25
"F0"  2.7   0.30
"F2"  3.5   0.35
"F5"  3.6   0.44
"F8"  4.0   0.52
"G0"  4.4   0.58
"G2"  4.7   0.63
"G5"  5.1   0.68
"G8"  5.5   0.74
"K1"  6.1   0.86
"K3"  6.6   0.96
"K5"  7.4   1.15
"K7"  8.1   1.33
"M1"  9.3   1.46
"M3" 10.4   1.51
"M5" 12.3   1.64
"M7" 14.3   1.80
"M8" 16.0   1.93	
  
Luminosity Class I

Type  M_V   B-V

"O5" -6.6  -0.31
"O7" -6.5  -0.31
"O9" -6.5  -0.27
"B1" -6.4  -0.19
"B3" -6.3  -0.13
"B5" -6.2  -0.1
"B7" -6.2  -0.05
"B9" -6.2  -0.02
"A1" -6.4   0.02
"A3" -6.5   0.06
"A5" -6.6   0.09
"A7" -6.6   0.12
"A8" -6.6   0.14
"F0" -6.6   0.17
"F2" -6.6   0.23
"F5" -6.6   0.32
"F8" -6.5   0.56
"G0" -6.4   0.76
"G2" -6.3   0.87
"G5" -6.2   1.02
"G8" -6.1   1.15
"K1" -6.0   1.30
"K3" -5.9   1.46
"K5" -5.8   1.60
"K7" -5.7   1.63
"M1" -5.6   1.69
"M3" -5.6   1.69
"M5" -5.6   1.80