Intercept?

[zapman987]

On target for Dres, and I dont have any intercept/SOI showing. Mess with some nodes, target closest approaches show up after a bit, with <100k.

What am I missing? As I can get target closest under 100k on both sides, but cant get an SOI showing.

[cantab]

Sure it's not a hundred megametres? Dres's SOI is about 32 Mm.

If you're making a flyby of somewhere else first, conic patch limit set too low? (Look in settings.cfg)

Hack Gravity left on? That really messes with orbits (unsurprisingly).

If none of those are the case, then there is a known game bug where SOI changes are not shown until they happen. This tends to occur with near-circular orbits just inside or just outside that of a celestial (and tends to lead to a crash after the SOI change, since you have very little speed relative to the celestial). You could try trusting that the close approach will give you the capture when you're there.

[Geschosskopf]

What am I missing? As I can get target closest under 100k on both sides, but cant get an SOI showing.

Well, if you're that close (and I assume that's Mm not Km) on leaving Kerbin, that's good enough to start with. I hardly ever get a Dres encounter directly from Kerbin but as long as I've got the closest approach down into the general area, that's fine. Just do a very small mid-course burn to finalize the encounter. The problem is that Dres' SOI is smaller than the smallest amount you can tweak the angle of your trajectory back at Kerbin when plotting the transfer burn. So sometimes you can hit it but often you jump back and forth to either side of it. But no worries. The important thing with any interplanetary transfer is to make sure you and the target end up in the same general area at the same time, which you can see with the closest approach markers. Thus, if you've got the closest approach down very small when you leave Kerbin, you can do a very small correction burn somewhere in the vicinity of Duna's orbit to finalize the encounter. The closer you get to Dres, the bigger angle it subtends, so the easier it is to hit.

[Kasuha]

Maybe you just ran into that bug when KSP doesn't see you'll intercept the SOI even though you will. Try to put a correction maneuver somewhere closer to the destination and see if you can get an intercept from there.