When the opportunity presents itself, I enjoy using mixed light sources like in this photograph of Trisha.
We were shooting in what I like to call the Blue Room because of the baby blue painted walls when I decided to turn on a bedside reading lamp behind me to my right. Trisha was backlit by the late afternoon sun coming in through the window above and behind her. (I could crop the window out by being slightly above her and angling the camera down just a bit). I turned on the light and tilted the head of the lamp up and toward her so that the tungsten bulb would be pointing directly at her. Luckily it was at the perfect height to allow me to create the Rembrandt lighting on her face. The metal hood on the lamp was round and helped spread the light and create a softer look than just a bare bulb would have.
After getting the lamp in position, I set the White Balance on my camera to Tungsten. The afternoon light became very blue by selecting the white balance for the light coming from the bulb. I shot the image with my Canon 85mm f/1.2 L series lens set at f/2.2; this created a nice bokeh and a very shallow depth of field while keeping her face in perfect focus, allowing you to get lost in her beautiful eyes.
I can pretty much guarantee that if you walked into the room while I was taking this photograph, you would not have seen the possibility of the image you see below. It is only through a series of creative choices in capturing the picture and processing the shot after such a stunning portrait is created. Sometimes shooting in a location is more about what you leave out than what you include, at least for me. Keeping the focus on my subject is most important.
Details of the shot again: Canon 85mm f/1.2 L series lens set at f/2.2, 1/60 sec, ISO-200