I am a new user of Vphot and trying to use transformation coefficients of my system with it. I have entered the coefficients into the telescope information but when I ask the program to start the transformation it delivers a message saying that Tv is missing. I attach a screen shot showing the data I have entered and the software message. I am using 2 filters (V and B) and the Tc's of my system are: Tbv = 1.302 Tb = 0.1178. Vphot asks to enter Tv instead. I would also like to know the procedure to transform magnitudes with Vphot as I couldn't find a tutorial in this regard.
Thank you for your help.