Camera settings for digiscoping?

[turboscrew]

I've been thinking of digiscoping Mars, but I don't have a clue about camera settings. My tube is 12" F/4 dobsonian, and I plan to use 6 mm (200x) or 3x barlowed 15 mm (240x) eyepiece.

I wonder if there are some rules of thumb for good starting values?
I'm talking about single shot pictures with no plans of stacking etc.

Maybe such starting values could be derived from the surface brightnesses of objects? Of course one has to take into account the TFOV and the object movement in the field, but I think that's not very complicated. If you know a good settings for a situation, where the tracking works fine and the object appears stationary, you can check if the shutter speed is fast enough. If it's not, you make it faster, and increase the aperture or step up with the ASA-setting, or maybe drop down the magnification.

[turboscrew]

I found this: https://www.saao.ac.za/~wpk/exposure.html
Do you think the K is really the same as (L/K) here ?https://en.wikipedia.org/wiki/Exposure_ ... conditions
And I wonder if K in the latter can be considered a gear dependent constant and L is the luminosity of the target?