In surveying with a drone the arguably best camera setting is to fix the aperture, to ensure sharpness and depth-of-field, and the shutter speed, to make sure there is no motion blur. The third part of the photogrpahic triangle is to set ISO to Automatic to ensure proper exposure.

Why can't DJI allow such a basic setting in Manual? There is a request for it on these forums from 2 years ago?!

Set your camera to aperture priority and f5.6, ISO to 100 and fly in daylight.
Problem solved

What kind of shutter speed will that give me on an overcast day?

tarkboffin Posted at 2018-8-14 05:32
What kind of shutter speed will that give me on an overcast day?

Test with your camera to find out.
If you fly in gloomy conditions, open the aperture to an appropriate setting.

It is this trial and error I want to avoid. I still maintain that the best solution is to be able to set auto ISO in Manual mode. This will ensure properly exposed images without motion blur in a survey, albeit with a bit more noise.

tarkboffin Posted at 2018-8-14 06:00
It is this trial and error I want to avoid. I still maintain that the best solution is to be able to set auto ISO in Manual mode. This will ensure properly exposed images without motion blur in a survey, albeit with a bit more noise.

And you've had so much experience that you know what's best.
Basic exposure isn't a great mystery.
It's easy to work out what your shutter speed is likely to be.
My suggestion comes from lots of mapping experience, try it or ignore it as you choose.

tarkboffin Posted at 2018-8-14 06:00
It is this trial and error I want to avoid. I still maintain that the best solution is to be able to set auto ISO in Manual mode. This will ensure properly exposed images without motion blur in a survey, albeit with a bit more noise.

To give you some actual numbers, the last mapping flight I did was giving me around 1400th - 1/500th on tree cover and faster with lighter areas.

That is useful advice, thank you.

Hello there. We apologize for the inconvenience. In regards to the settings, that will depend on your preferences on how you would like your footage will be. But don't worry, we will check this request to our engineers. Thank you for reaching this out.