Generally on the D800 I use a zoom, ether 24-70mm or 70-200mm, and when shooting wildlife either a 105mm or 300mm telephoto.
All my other cameras I use primes and since about April I have nearly always had the 50mm Summilux to hand on my Leica M10. Its been a challenge as it never quite seems the right length but one that I have persevered. Come April i’ll have been using it for a year and will switch to the 35mm Summicron for a year.
During my last studio session I tried too shoot everything with a 70mm, this is also part of a long term test and deciding what focal length I want as my main go to studio portrait lens. While a 50 is great for full length shots, the 70 is better for head and shoulders, i’ll also be doing some tests at 85 and 90mm.
While Canon and Nikon tend to go for just 85mm as there portrait lens, Leica have 75mm and 90mm and Hasselblad go for 75mm.