saluting crew
Whilst I never did or even saw others doing so, I did insist that my staff (including myself) ALWAYS called the Capt either Captain or Sir when they were working. Didn't matter which but had to be one or the other. I had many discussion with Capts who said "call me Jack, or whatever," but I always said outside of the Cockpit and out of hearing of other Crew Members I will, but otherwise Captain or Sir would be used. Even though I walked around with 4 stripes on my shoulders and sleeves, I did what I insisted my staff do. It worked for me, it showed respect for their position and they then showed respect for mine.