Normally I don't sharpen my knives in the field. I carry a couple which is good for 5 or so sambar without having to sharpen. However if you are going to sharpen in the field I have recently bought the Sharpal 210N unit. It has diamond, ceramic and strops on it. It has an ingenious way to set variable angles so with a bit of practice you can get a knife shaving sharp in minutes from scratch
https://www.amazon.com.au/SHARPAL-210N- ... 9hdGY&th=1
I also use several knife sharpening kits but in some recent tests with some work collegues we got outstanding results for free hand sharpening with the Sharpal 162 which can also be packed in the car and with a bigger surface area can bring the long knives back quickly. Although I still recommend a kangaroo strop with some diamond emulsion for finishing.
https://www.amazon.com.au/SHARPAL-Diamo ... r=1-5&th=1