Fer, if your monitor has false color its a handy tool to find the right skin exposure and avoid over and under exposure.
For the sony Alpha series I usually use a mix between Waveform and False Color. Use the waveform to check the exposure and be careful not to compress your image, as the camera is 8bit you will be loosing lots of shades when grading if you do.
Regarding Luts you need an external monitor that supports them. Try to over expose between 1 to 1 1/2 stop, if you go for 2 full stops you might be crunching highlights and it will be hard to grade afterwards.
Depending on the external monitor you have it will only show the tools reading your LUT image or you might have the option to bypass the LUT and show you the tools reading the Slog signal. Thats an easy guess, as the Lut for sure will contrast the image and looking at the waveform you will be able to see if its readig the LUT or not.
Agustin Barrutia (ADF),
Buenos Aires, Argentina,