The Boathouse Steps Are Stupid

Ugh. I’ve indeed proceeded to the boathouse steps, and it turns out that they’re evil.

It all started out innocently enough. There are super detailed drawings available for the Deathly Hallows version, so I started there. I figured I’d work backward to the GOF/OOTP/HBP version, and then finally to the SS/COS/POA version. Above is the DH version in the process of being built, along with a newly wavy lake surface. Below is what they looked like when I was done:

Okay, so far, so good. It looks weird, but that’s just because they’re untextured, they don’t have any walls, and they don’t match up with the POA castle around it. The technical drawings were very explicit and internally consistent, so I felt very confident in this setup. Next up: the version from the middle three films! Should be easy, right? Just follow the floor plans, and then adjust the height to match the exact vertical distance between the boathouse floor and the viaduct courtyard floor, right?

Wrong.

It all went askew when I compared my steps to this angle of the HBP model at Warner Bros*:

See how the steps come right up to the bottom of the boathouse roof? Yeah…mine didn’t do that. They stopped noticeably lower. Something was off with the vertical scale. Presumably, some of the flights were supposed to be steeper than others. But it also occurred to me that my vertical measurements for the boathouse weren’t particularly precise either, so it was risky to try to get these disparate approximations to match up with each other.

No problem! Fortunately, this version of the castle has better photographic documentation than any other, since it’s open to the camera-wielding public. I was particularly enthused when I found this video – I knew Meshroom would like the camera motion, coverage, and image quality. So I fed a bunch of frames into the photogrammetry software and let it run. Actually, I let it run multiple times on different subsets of images – running everything all together resulted in some errors. Then I plopped all the different scans together into the same physical space:

Not exactly pretty, because this is a half-dozen scans with different lighting poking through each other haphazardly due to the limited precision of this method – plus lots of junk data floating around. (A lot of the stuff up top is the lighting fixtures from the Warner Bros. Studio Tour, haha.) Still, I figured this should provide some good reference, right?

Well…it turns out that the floor plans don’t quite match up with any of the scans. So that’s annoying. Again, it’s probably the result of the limited precision of this photogrammetry, but it makes it tough to trust this information.

And that’s really where I’m at right now…still trying to figure out the boathouse steps. I may end up needing to adjust the boathouse’s vertical scale, too. Oy…wish me luck.

* Apologies to the photographer for not giving credit. I’ve somehow lost wherever I found that image. If you recognize it as yours, please don’t hesitate to let me know!