Calculate the Absolute Magnitude of Sun I Band

The calculator calculates the absolute magnitude of sun I Band. It calculates absolute magnitude of sun I band based on the observed maximum rotation velocity and galactic inclination. Tully-Fisher relation was published by R. Brent Tully and J. Richard Fisher in 1977. It is a relationship between intrinsic luminosity of spiral galaxy and the width of its emission lines.
Formula: I ≃ -7.68 log10 (2vrot / sin i) - 2.58
Where, MI = Iband Absolute Magnitude, vrot = Observed Maximum Rotation Velocity, i = Galactic Inclination
Observed Maximum Rotation Velocity:  km/sec
Galactic Inclination: 
Iband Absolute Magnitude: