The Laser Placenta

leading from  

Design Of The Derelict

a) In the silo, below the jockey's chamber, there are thousands of spores that must surely be as old as the Jockey's remains. They are covered over by a film of blue light that is a laserbeam spread like a thin sheet, and there is a sound as the astronaut penetrates the laser beam's field. It represented the placenta of the eggs

(from Alien Anthology blu-ray)

(from Alien Anthology blu-ray)

(from Alien Anthology blu-ray)

b) Ridley's original idea for the sequence was cut for budget reasons. His storyboard had Kane going down a long tube and then emerging into this massive chambers through a hole in the ceiling. Before he does though, at the bottom of this tube he finds a very thin membrane which he cuts through and this feint breeze drifts upwards as he descends into the blackness. But he can't see anything, so he says "I'm going to light myself up' - and what Ridley wanted were thousands of tiny pea lights stitched into his suit so we could light him up like a Christmas tree and have him hanging there from the roof of this cavern, like some beautiful chandelier. He thought it would be a marvelous image.

(from Alien Anthology blu-ray)

c) But since the whole approach was out, he wanted something to replace the membrane, which he saw as a kind of a biological alarm which triggered a response in the eggs - they all come awake and sit waiting to be touched, basically. They finally settled on a laser which was mounted so it would scan just above the eggs and give us this sheet of blue light. They could have done a lot more with it, but we didn't have the time. As it was, they only had about half a day to test it and then another day and a half to shoot the whole sequence.

(from Alien Anthology blu-ray)

d)  It was a fairly strong scanning laser. It belonged to The Who rock group - they use them in pop concerts and such - and it operated at about three thousand cycles per second with a sweeping arc of about fifty or sixty degrees. Basically what's happening is there's a mirror in there that's oscillating three thousand times a second. If you could stop the mirror you'd get a single point of light, but when it's moving it's not dangerous because you's subjected to the power of the laser for shorts bits of time. Since the laser's scanning so fast and you camera's only running at twenty four frames per second, you get quite a number of scans on one image. The light level is very low, though, so everything in there had to be shot absolutely wide open and with the wizardry of Derek Vanlint's cinematography. And they had to use a lot of smoke; otherwise it doesn't show up at all because the beam's only bright when it doesn't show up at all because the beam's only bright when it's actually touching something.

(from Alien Anthology blu-ray)

e) Despite the face that the placenta had now become noticeably like a sheet of laser light which brought people to ask other questions about what it might be since it became much more technological, but for Ridley, it remained as a placenta wall and when Kane broke throught it, Ridley had added a sound to the laser beam which sounded to him like a seal.

(from Alien Anthology blu-ray)

source quotes :

1. Ridley Scott: My original idea for the sequence was cut for budget reasons. My storyboard had Kane going down a long tube and then emerging into this massive chambers through a hole in the ceiling. Before he does though, at the bottom of this tube he finds a very thin membrane which he cuts through and this feint breeze drifts upwards as he descends into the blackness. But he can't see anything, so he says "I'm going to light myself up' - and what I wanted were thousands of tiny pea lights stitched into his suit so we could light him up like a Christmas tree and have him hanging there from the roof of this cavern, like some beautiful chandelier. I thought it would be a marvelous image. (Cinefex 1, p65 and Alien Special Effects, p37)
2. Ridley Scott: But since the whole approach was out, I wanted something to replace the membrane, which I saw as a kind of a biological alarm which triggered a response in the eggs - they all come awake and sit waiting to be touched, basically. We finally settlied on a laser which was mounted so it would scan just above the eggs and give us this sheet of blue light. We could have done a lot more with it, but we didn't have the time. As it was, we only had about half a day to test it and then another day and a half to shoot the whole bloody sequence
   (Cinefex 1, p65 and Alien Special Effects, p37)
3. Brian Johnson: It was a fairly strong scanning laser. It belonged to The Who rock group - they use them in pop concerts and such - and it operated at about three thousand cycles per second with a sweeping arc of about fifty or sixty degrees. Basically what's happening is there's a mirror in there that's oscillating three thousand times a second. If you could stop the mirror you'd get a single point of light, but when it's moving it's not dangerous because you's subjected to the power of the laser for shorts bits of time. Since your laser's scanning so fast and you camera's only running at twenty four frames per second, you get quite a number of scans on one image. The light level is very low, though, so everything in there had to be shot absolutely wide open. And we had to use a lot of smoke; otherwise it doesn't show up at all because the beam's only bright when it doesn't show up at all because the beam's only bright when it's actually touching something. (Cinefex 1, p65-67 and Alien Special Effects, p337-9)
4. Ridley Scott: The sheet as I call it of the laser beam, this is a laser beam spread thin like a thin sheet, but it worked great here and I never thought it would photograph because it's pretty low key, but you know, with the wizardry of, of Derek, we got it. So this is all just handheld lay the sound on as you go through the laser beam, you can here, there's a sound to the laser beam, you can hear it now, like a seal. I always thought of the laser beam as the placenta wall for the, erm, eggs.(Alien 30th Anniversary Edition DVD)

(from Alien Anthology blu-ray)