KSP v1.4.0 O-10 "Puff" engine clustered plume

[Raptor9]

I was testing out various engines to see their new sounds in atmo and vacuum.  To test the O-10 "Puff" monopropellant engine, I took one of my imported 1.3.1 craft files, Alt-F12ed it to LKO, and started burning the engines.  I noticed that individual O-10 engines operating alone, or visually separated from the plumes of other O-10's, seemed to behave as before.  However, if a cluster of O-10's were within (or close to) the same line-of-sight, the plume effects seemed to converge to each other as if drawn together.  I reverted back to the VAB, and put "new" O-10 engines in case there were any 1.4 code changes (not a programmer here obviously), and the result was the same.

In the second frame it even appears as if one of the plumes is hugging the horizon, but that may just be me.  The bottom two you can clearly see the plumes being drawn to each other.  To reiterate, this behavior only seems to manifest when multiple O-10's are running within the same visual sight line.  As I panned around the outside of the lander, the plumes would contract and expand depending on the visual angle.

Obviously not a game-breaking issue, just quite an odd sight considering the O-10 is a vacuum engine and if anything the plumes should be expanding, not contracting inwards on one another.

KSP version was 1.4.0 (64-bit), being run on Windows 7 with dual Nividia GeForce GTX 680M graphics cards in non-SLI mode.  Clean install, no mods.

Edited March 7, 2018 by Raptor9

[rudi1291]

The release notes mention a particle system upgrade. And when 1.4 was first announced, there was speculation, that they might use it for engine plumes. Maybe thats that in effect? 

[Raptor9]

14 hours ago, rudi1291 said:

The release notes mention a particle system upgrade. And when 1.4 was first announced, there was speculation, that they might use it for engine plumes. Maybe thats that in effect? 

I'm aware of the new particle effects, but the behavior of the plume is weird.  Try clustering several O-10's around each other, throttle up, and pan around them from different views and you'll see what I'm talking about.  I know the particle effects changed, but the behavior is odd at best, even for KSP.

[Majorjim!]

Seems there are a few bugs with the new 'improved' particles. They move and rotate when the camera does which looks a bit poop. Yay progress!