Config File Questions

[Streetwind]

I've read somewhere that you can change the physics simulation timestep in the KSP config file. Usually people do this to unlock extra performance, but I have a very good computer, and I'm curious: are there any advantages to doing more calculations as opposed to less?

I'm also somewhat annoyed by the way my apoapsis and periapsis points start jittering like mad as soon as I get them under 2 km of each other. I kind of like my near-perfectly circular 72km orbits around Kerbin, but all I can see is the markers spazzing all over the place. Is there something I can set in the config to maybe increase the resolution or whatever it takes to make the markers more precise?

[TechnicalK3rbal]

No, that's because your craft is moving and shifting the center of mass very little, because the games physics calculatoins are so precise.

[Kasuha]

Regarding physics step, as far as I understand it, it is only used when your framerate drops. Until then, the game makes as small physics steps as possible (delta t = time since last frame). This value actually prevents it doing too big physics steps. Big physics steps may lead to structural failures and other problems similar to what happens in high physics warp. Smaller physics steps mean more reliable physics simulation.

Regarding Pe/Ap jittering, it's result of how the game is implemented. Sometimes it causes problems, e.g. when placing a maneuver on such orbit. Then you can force them still by entering time warp (x5 is enough). Apart of that, it's better to not use circular orbits.

[Streetwind]

But then how am I going to get something geostationary, if I making the orbit circular is such an issue? As far as I understand it, that needs to be done super precisely, but the second apsis at least will be jittering so much that it's impossible to see its value within a large margin of error. Is being in time warp precise enough to set it up?

And now for something completely different: if I import a craft file of a vessel, and I am in career mode, and that vessel uses one or more parts I have not yet unlocked... what happens?

[Kasuha]

orbit:

You don't need circular orbit to make the ship position - more or less - stationary. If you hover mouse over Pe or Ap markers, it will show you its height and time it will take you to reach it. If you click on it, it will stay displayed. All you need is to make the orbit somewhat circular and make sure the two times displayed below Pe and Ap marker are exactly 3 hours apart.

career:

It will tell you it contains parts you don't have and won't allow you to load it. Just give it a try.