Trying to figure out if this shot (23:50) in 2001: A Space Odyssey is a camera movement or a zoom happening. I'm pretty sure it's a zoom but some confirmation would be helpful. For those that are wondering, I'm making a short video essay on Kubrick's zoom technique, and would love to be able to take an example from 2001.
As [we are fairly sure] we know, Kubrick used spherical lenses not anamorphics on 2001, we can use a simple perspective test to see if it was a zoom or camera move.
If you move the camera, perspective will change. If you zoom, it will not. [This is physics 101.] This is harder to test on anamorphic lenses as they also change image framing as you pull zoom in quite a complex way - so let's be glad we don't have to compensate for that too.
By the simple expedient of taking an early and late frame & re-sizing one to fit over the other, you can tell this is entirely a zoom.
I have intentionally stepped this out by 20px vertically so you can see it. Accurately lined up, there is no discernible perspective change at all & therefore the overlay vanishes entirely.
Because of the difficulty in hand-matching the compositing for the 'windows' you would have to assume this was all done in post; so it was all shot at the widest and zoomed after compositing. Otherwise the compositing would have to be hand-matched for every frame. A nightmare of a task when everything was done by hand.
I can also find no reference to Kubrick using zoom lenses before Barry Lyndon, which would add weight to this argument.
 This confuses photographers too, especially when using crop-frame cameras, so I did a beginner's guide on PhotographySE - How does crop factor affect perspective? - if you want to see this in practice.
9I know my comment will need removing but before it does, Jeez Louise Tetsujin, you are bloody clever and despite this not being my question I thought both it and your answer was excellent. I knew about the use of the round lenses as opposed to anamorphic but this provides practical context for that decision Apr 25, 2022 at 14:25
1Thanks. I was pretty sure this was a zoom, it was harder to be sure with the background being black. I was actually able to find 2 zooming shots in Lolita, a whole bunch inside the plane in Dr. Strangelove, 2 in 2001, and a whole bunch more in A Clockwork Orange. Still need to go through Barry Lyndon, The Shining, Full Metal Jacket, and Eyes Wide Shut which I know there are a lot of. I'll post the video on here when I'm done. Apr 25, 2022 at 16:48
"so it was all shot at the widest and zoomed after compositing." So does that result in a loss of resolution? Apr 25, 2022 at 19:52
1@Acccumulation - not if the compositing was at its highest resolution as it were. With film its harder to see if that happens, with digital it is very obvious as the resolution is digital (fixed pixels) rather than analogue which has a organic feel in the form of grain, which can be more forgiving. If you see any BTS of vfx for films where they paint mattes you will see that they are extremely large. That removes the problem of 'loss of resolution' as they have such a large format to start with. Apr 25, 2022 at 21:36
1Roger - it would be interesting to have a look at those earlier examples too. Do you have timestamps for any of them, save me going through entire movies looking for them? Barry Lyndon, of course, is famous for them. Half the film is shot in a kind of tableau, with a pull zoom. Always makes me think of Greenaway. [Of course,. the other thing BL is famed for is that F0.7 lens… which frankly isn't all that convincing. It's way too soft for my liking. Of course you could do it on a T2 these days, with high ISO.– TetsujinApr 28, 2022 at 9:19
It's a combination of both zoom and camera movement.
The difficulty figuring this scene out might come from the fact that the live scenes are static recordings (of live action scenes), and either projected behind the scale model of the docking pad, or — more likely — superimposed afterwards.
Since these four frames (coloured in the picture below) are static recordings, they are zoomed out of while the rest of the docking scene is actual camera movement.
Using the same method as Tetsujin did in their answer, it becomes obvious that the angle from which we see the live-action superimpositions don't change, and they are indeed simply scaled to accommodate the camera movement of the miniature of the docking bay (that is unless they are projections):
1There is Star Wars scene filmed in a similar way - I'll see if I can find the VFX breakdown of it. Apr 25, 2022 at 7:55
3Star Wars had a programmable motorised camera dolly which could repeat the same move ad-infinitum. 2001 didn't. There is a world of difference in how similar shots would have to be done because of this.– TetsujinApr 25, 2022 at 8:08
@Tetsujin I'm talking about the combination of the static images and the zoom (in my comment comparing it to SW). I don't have enough knowledge about the technical side of things, so my answer is based on visual analysis rather than a technical one :) Apr 25, 2022 at 8:10
1@Joachim, I think Tetsujin was saying the scene in 2001 was a zoom and not a camera movement. Apr 25, 2022 at 16:51
5@Tetsujin I think I have completely misjudged your comments, I see now that the OP commented on this. No wonder you might have gotten somewhat annoyed. My sincere apologies. Apr 25, 2022 at 17:26