The production designer, the costume designer and myself worked to make tentacles that could be created in reality, like puppets. Edge FX created how the puppets would work. Of course, [Sony Imageworks] animation director Anthony LaMolinara and the animators worked with us side by side as the puppets were being created - both the physical tentacles and the designs for the CG versions — to make sure that we incorporated elements into them that would work for the animation. There was a really tough set of criteria that was placed in front of the animators with respect to creating the personality of these tentacles.

Of course, during the design phase, Alfred Molina, who had to wear these things, also had input. It was quite a collaboration — with Sam, of course, as the arbiter of all the things that would be included in these tentacles. They took a long while. In some form or another, they were in development even past the beginning of principal photography.

Vfx builds of Doc Ock’s lab as it’s being destroyed.

EW: What were your criteria for when the tentacles would be puppets vs. CG?

JD: There were mechanical tentacles wherever the character had to come into intimate contact with them. If the tentacle had to grab him around the throat, or light his cigar and hold it to his mouth, or take off his sunglasses — it was done with a puppet.

The tentacles were, variously, four feet long and 18 feet long, depending on what we needed them to do. We discovered that if we used the full-length tentacle we had to have three pieces. So if we had all four tentacles on the character, it would be him plus 12!

Generally speaking, the puppets were used in the close-ups and in the medium shots where the tentacles didn't have to be any more than three or four feet long. The CGI tentacles took over from that point on, for the most part.

EW: What were the most challenging aspects of doing the hand-offs between the puppets and the CG tentacles?

JD: There were lots of places where there would be a live-action puppet tentacle in the foreground that would go off-screen, and then come back on-screen as a CG tentacle. We had puppets and CGI mixed in the same shot. The trick was making them all look the same. And that was difficult.

Audiences are familiar with things like metal and rust. So making a CG version of something that was real, photographed on camera, and then combining them in the same shot was tricky. All of that CG stuff had to respond to light in the same way that the real objects responded to light.

Another view of Doc Ock’s lab during the explosions.

Also, Doc Ock's tentacles did things that they couldn't do in reality. They had mechanical attributes that we couldn't have had in any real device. So there was a lot of stuff done with the animation that stepped beyond the bounds of the physics of the real world. That's the tough part of doing this stuff.

We had to make sure that the center of mass of the tentacle made sense. There was a huge amount of work that went into creating the “characters” of these tentacles, to make them be at once mechanical and organic. The tentacles had to look as though Doc Ock was controlling them with his brain. They were supposed to be tied directly to his hypothalamus: to be lower brain functions. The tentacles themselves were supposed to move as if they were extensions of his own physiognomy. Alfred loved working with the puppets. We often did a shot with the puppets and then did one without, in case we had to add the CGI. It was such a joy to be able to make these things do this crazy stuff that they couldn't ever possibly do. That's the best part of making movies!

EW: Were there any aspects of making this movie that took you by surprise?

JD: At the end of the movie, a climatic fight between Spider-Man and Doc Ock takes place on the pier, which for the most part was a miniature. We had miniature water when we photographed the miniature pier, and it was decided that we needed more activity. So we had to do CG water at the last minute. That was something that we had to develop and put into the shot over a very short period of time. Water is difficult because it doesn't scale worth a damn.