Cannon ranging bugged in specific areas & directions unrelated to wind/velocity

[Volk.]

This was originally posted by Szmarty on reddit/hoggit. Specifically their training mission ("TNN") has targets South-West of Kobuleti (that famous "X" everyone loves to use for target practice.

This has nothing to do with the other bug reports on contrast locking - purely on ranging, possibly specifically how it affects the cannon.

Laser-ranging the 2nd furthest target, or anywhere in the area near it always results in the cannon rounds falling short. This is from a windows-key + home autostart, standard rocket + vikhr loadout, set in manual mode. INU, K-041 and everything else important is on. The laser is not burnt out (not that that matters for cannon ranging). The target is not moving, nor is ground moving target on. Wind is 3m/s from 111, so from the left in the early shots.

Without resetting the Shkval - locking up other targets the rounds land accurately. Firing from a stable hover.

Ranging far into the distance and locking dirt (no contrast lock, just the 3 second ranging), the shells land accurately. But anything in that patch around that 2nd-from last vehicle lases weirdly. One can also see the ABRIS shows the laser-ranged Shkval gates as looking near the middle of the airfield or closer, rather than on the furthest edge of the runway.

After flying to the other side, now my heading is maybe 028, but in a sideslilp with track of 008. Laser-range at 3.9km. It's stopped ranging for a while already when I open fire at 3.2 on that same truck that gets the ranging weird. All shots about 3m off to the right (I don't find this too strange/disturbing - but rather I'm saying now the rounds are neither falling short nor overshooting by far). The wind would have been an absolute crosswind in this situation from the right. Fire again at 2.7, 1 of the rounds hits home, rest very close spread on the right.

I've seen areas in DCS where slewing side-to-side without lasing massively spikes the ranging, but that's with the laser off and always in high areas. This is with laser and near sea level and something is very wrong there. In hindsight I should have launched a Vikhr as well, though I'd guess it would follow it's way to the target and the 6 second buffer would cover the ranging error.

This particular case is like a small Bermuda Triangle area, but only from one side.

Video capture: https://www.youtube.com/watch?v=oZ4odwdMc74

I have a trackfile, but it's 38mb - not from an excessively long flight, but I guess mostly the mission. Can't seem to compress it down to the 5mb limit. Please advise on how to share that.