Quoted from howdoyouafford:

Hi, I don't have any pinball but whitewater is the one I have the fondest memories of, especially the topper. I read through this thread and I made me curious how one would reproduce the topper. Earlier it was mentioned that Philip Grear was the original artist who made the effect and had some deal with Williams and was involved in making it. I found he has two patents on the subject:
6,760,959
6,361,702
Both of these seem to be the same process, You take a .0003" aluminum foil and layer it onto something pliant of the same thickness then mount it to a plastic plate and micro engrave parallel lines on the surface at about 100/inch. The artistry comes in making the lines in swaths that differ in angle so chaser lights reflect off of them to make the animation. I might buy a cheap damaged topper to put it under my microscope and see the artist's work, or what's left of the evidence. Then you electroplate nickel and iron onto the foil to .01-.03" and then peel the foil off of it (destroying the original I imagine) and stick it in a web offset printer cylinder and then use metalized mylar and heat pressing which will seal the mylar to a print coming out of an offset color printer in the outline of the die cut you make and press the engravings of the die into it in one pass.
Trick is, it's still covered by these patents. I think it's 20 years from 1999 or 2001, so not sure if his estate still keeps up on the patent. The referenced patents are an interesting read.
I found another modern company "Dufex" that prints those decorative pattens in packaging and their similar patent
5,168,646
Which Grear references, patented in 1991. What's interesting is the patent I found that google referenced with the UK based Dufex was actually registered to NCM International Inc in Chicago where Grear was/is based. (I heard mentioned he passed in this thread or another? If so, i'm sorry to not have the chance to talk to this fellow.) There seems to be some history with this graphics trick. It's referenced in the wikipedia article on Lenticular Printing, though not a lenticular process and the image is created differently, but applied the same way holograms are to things like credit cards.
Which leads me to believe you'll have to do some microscopy to see the original engraving art from the White Water topper and save the pattern to a computer and re-engrave it by CNC or even do it close enough by hand which would be quite the work, then there is even mention of an acid wash (though not which acid to etch nickel/iron) to deepen the ridges after the electroplate to make a sharper depression, and the photos of the reproduction in this thread that were not 'good enough' seemed to be a full sheet of foiled cardboard like a bounce card material due to the metal background around the border of the print, where the original seems to be a hot transfer only where the foil part of the image is. I don't think this has the reflectivity of the original, mylar is quite striking when metalized like those plastic metal balloons you see at the florist or those greeting cards with unicorns and shimmering backgrounds.
I got obsessed and didn't want my research to go to waste. Hope it's interesting. Links to patents and materials removed cause it's my first day with a username.

Quoted from mbaumle:

So I picked up a White Water over the weekend, and the first thing that really drew me to the one I bought was that the topper was nearly flawless.
When I showed my dad, and explained to him that these things sell for hundreds and hundreds of dollars, and told him the sad tale of the failed reproductions, he said "huh." (As he looked at it closer) "This doesn't look like it'd be terribly difficult to reproduce. It's definitely doable."
"Well, yea. It's basically a metallic version of those weird 3D things that have a pseudo-holographic effect to them--like those rulers we'd get in elementary school that when you move it, the picture animated itself. Or the hologram in Creature from the Black Lagoon." I exclaimed.
He goes, "No, this is different. This is a special printing technique. I used to have a colleague who's specialty was this. We would do almost the same thing for book covers and magazines. There's a moving light source that gives the effect of the waterfall, right?"
(This was before he saw the topper attached to the game)
Anyway, long story longer, my dad works for a book publishing company. He knows all the special printing techniques that are used for all sorts of printing--including special custom projects. He used to know a guy who ran a business that would produce prints of things that did exactly what the White Water topper does. Unfortunately, the company went out of business a few years ago, but he seems confident enough to be able to find this mysterious guy who might hold the secret to making a repro. He said he might even have a contact in the publishing company that might be able to make a functioning example.
I'm not trying to get anyone's hopes up, as I doubt any of our contacts will come to fruition, but he claimes that if anyone is going to be able to make a reproduction topper, we (as in people in the pinball community) should find a "book cover printer/designer." And that style of printing would create the desired effect.
I'm going to keep my ears on the ground and try to dig up some more information from my dad. He's going to make a few calls to see what could be done.