It's very clear that different proportions were used depending on the scale of the model needed for a particular shot, especially how far the bottom perspex shell curved upwards around the strobe, and the position of the 'aerials' (connection points for the suspension wires and power?). They were roughly in the middle for smaller models but much lower and nearer the rim on larger ones, presumably for great stability as the middle silver section and lower strobe spun independently of the outer shell, as for example in Computer Affaire (into a forest), Flight Path (on the moon), and The Psychobombs (slow descent into trees).
I deliberately created more detail simply because when seen in close-up the model would otherwise be rather boring, so what was simple ribbing has been changed from my first rather flat rippled attempt to sharply defined vanes that are highly reflective and so hopefully create a nice glittering effect. I also made a small change to the motion, obviously keeping the central spinning vanes and lower strobe but keeping the bottom dome and especially the thrusters static along with the top dome and everything above the green ring, for having spinning engines makes absolutely no sense for any kind of stable flight and descent control, though even here there were vast inconsistencies with some models having only two exhausts (Destruction) and the larger models not having anything protruding below the lower dome so that they skidded easily.
Two images above my bland desert. As the vanes and domes are slightly reflective, some areas have a yellow tint due to the sand beneath. The domes are deliberately rendered without refraction otherwise the ribbed vanes are too distorted to be clearly visible, and the original model perspex didn't have any noticeable refractive qualities anyway.
Flying in space from the sun with deliberately clichéd lens flare.
Composited with 'real' backgrounds (unknown rocky landscape, and Split Rock Lighthouse, Two Harbors, MN, USA). The most obvious mistake is that the shadow in the second flyby cuts off abruptly, and of course the CG image is far too clean, but at least the grounds aren't flat as in my originals. The UFO's rotation is also slower than it ought to be, but it was tricky finding a balance between seeing detail and having a blurry mess.
More messing around with volumetric textures. In reality nothing would be visible inside, but I wanted more of a gaseous effect than pure flame and smoke, and the vehicle is probably protected by an electro-magnetic field generated by the spinning vanes, hence the prominent leading edge, and there's a nice flickering effect form the vanes.
A learning study in volumetrics (though I was originally more interested in the motion): missile trail, missile-impact explosion smoke and separate sparks, dissipating orange and red smoke from the UFO and red smoke from the vane that was blow off, three sets of ground impact debris with one moving as the UFO skids, plus some dust. This is the first time I've attempted an animation of this complexity (all I've done in the past are relatively simple fly-throughs), and was a wonderful example of the large gap between knowing the theory of how something is done and actually setting up the multiple FX emitters and arranging them in different combinations affected by wind and gravity, whilst all the time being 'aware' of objects and so not passing through them.