Let me start out by saying that I am fully aware that I do not entirely know what I am doing with Keyshot. There are things I don't know exist, things I don't know how to use, things I don't know what they are supposed to do, etc. I watched the videos, they are good slick marketing tools. It's very difficult to gain a real understanding from them, past "it's cool and it probably does what you want".
1) The lathe thingy was never intended as a rendering. It was from a different question quite some time ago. Just ignore it, I didn't even import it to this thread, someone else did. I used it ONLY as a comparison of processing times, which is why I think it was brought in at all.. The shiny surface deal is weird.... I have nothing to do with it.
2) Tweaking, sure. My problem is I have tweaked the thing until I was blue in the face and I still got nothing I liked, nothing that looked at all real.
As it happens, I am not concerned about ultimate detail. I do not need a diamond ring rendered, as in one of the videos. What I want is something which looks real. Real-looking has no actual resolution limit, things look real because they do, it doesn't suddenly start at 600 dpi, 1202 dpi, etc (as long as you stay out of solarization etc). A blurry photo can look real, or fake, and you know it when you see it.
The sink is particularly odd, because the top looks mirror-smooth, and the "bowl" looks like a rough cast surface. That CAN be right, because at a low angle, even a matte surface develops a specular reflection characteristic. (that's actually a measurement of roughness, the reflection angle). In this case I do not think it IS right.
The sink doesn't seem right even on the top. I can walk over a ways and LOOK AT a sink, and it doesn't do that. With reflections, I see the linear pattern in it, and the reflections follow that. NO WHITE SPOTS.
I can't find controls that let me get the appearance. "Bump" makes things worse, it isn't the right thing. Heavy brushed is wrong, it is "too much", AND it still tends toward the same problems I already see.
A BIG problem may be the "white spot issue". That is something KS seems to be doing. They may average out to be correct over the area, but they are artificial and wrong-looking, and I don't know how to get them to go away. They may be at the root of the sink bowl reflection issue.
3) Computer power.....
Maybe.... But when the rendering completes, that's all you get. It isn't a case of power (affects time to finish) but of the material model in KS, which does not get the desired result, and seems not to have ways to get there. Not ones I understand or know to use, anyway. I don't think computer power puts white spots in, either.
Computer power may affect the limits placed on the rendering, the selections, etc, and they may affect realism, of course. But even when I have set it to "slow and good" settings, I didn't see a change in the stainless brushed finish.
Maybe it's just too hard for keyshot to do.
4) Lighting....
Well, OK, but I am stuck with the lighting sources I have. That's where they are, and so that's what they will do. I can play with intensity and color within limits. Adding lights..... that won't cut it for an actual space.
Since I don't know how to fix it, really, the best stock material (still not really great) is "brushed radial" SS.
I attach a sink basin (no drain!) with the radial brushed.
Actually, no I don't, I can't attach a .ksp file here. Nor a .bip. Well phooey.