DSLR Photometry on Carbon Stars?
I have another question regarding DSLR photometry. I was looking over a list of variable stars that should be bright enough for me to use my camera and zoom lens this coming weekend. I saw X Cancri, which looks bright enough and seems well positioned for me this time of year, but then I noticed it's B-V color index of about 3.3. My question is with a star this red, can we use the same technique of measuring the "tricolor G" magnitude and applying the Transformation Cooeficient to obtain a measurement that is comparable to a Johnson V measurement?