At 22:19 tonight I was out in the back garden equipped with camera, tripod and shutter cable release, waiting for the first of four passes tonight by the International Space Station over the UK. The sky was almost completely clear of cloud apart from a few wisps, and there was no breeze so it was a perfect evening for long exposure shots of of the night sky. I didn’t see the station, however, because I was busy setting up the camera kit. It had been a last minute decision to try to capture the ISS. I’d just been reading Twitter feeds and saw a message from Virtual Astronomer retweeted by Prof Brian Cox, alerting the world to the bright passes tonight. It will be pass overhead several times again over the next few days but the weather forecast is bad, especially for Saturday.
Still, according to Meteor Watch, there will be many more passes over the UK during June, and it will return in August evenings during the Perseid Meteor shower, but perhaps my best chance of photographing it will be to wait for the second pass tonight at 23:55. I’d better go and make sure the kit is ready in time, because although I might be around to capture the third pass at 01:32, I definitely won’t be awake for the final pass at 03:08.
Update at 23:59. The pass was definitely “overhead” as described on Meteor Watch, so much so that my tripod head couldn’t cope. Ah well, it was still a splendid sight in a clear night sky.
The copy of Cinefex (Issue 85, April 2001) which I ordered recently from America has arrived. I bought it in the hope that its long article on ‘2001: A Space Odessey‘ would contain a thorough description of how Douglas Trumbull created the Star Gate sequences, since the limited amount I could find on the Internet wasn’t detailed enough. And now I know why.
The fascinating article discusses many aspects of the filming and describes some of the slitscan techniques at length (pp110-113), but it’s hard to grasp exactly how it was done. I suspect that I’ll have to watch the film and re-read the article repeatedly before I could work out to do something similar. Still, it prompted me to relook at the pioneering abstract animation by John Whitney, such as Catalog (1961) and Arabesque (1975), and following those links reintroduced me to Karl Sims, whose low-tech three-pendulum rotary harmonograph looks like a fruitful source for converting to Processing sketches.
Perhaps the appeal of these pioneers is that the special effects in films like ‘Inception‘ are beyond the scale of a small group of dedicated people working on a film like ’2001′, so they feel inhuman, a degree of perfection beyond the ‘uncanny valley‘ of robotics.
The exhibition was much larger than I expected, and covered many types of undercover images, starting with innocuous informal shots taken surreptitiously on trams and in the street. Celebrities depend on publicity, but the shots of Richard Burton and Elizabeth Taylor relaxing on a yacht made me feel surprisingly uncomfortable.
Countering this, the long slide-show of a photographer’s friends and family felt warm and relaxed, an intimate collection where faces became familiar. But that was a brief respite, for soon we were at what felt like the nadir of the exhibition – death. Victims of urban crime were followed by victims of genocide, executions and lynchings.
After these imagees, conceptual photography and photographs about espionage seemed insubstantial and tiresome. We needed a long break before we could attempt the drawing class, but that’s for another post.
In the end I didn’t bother to assemble a video clip from my slit scan experiment. Many of the frames were over-exposed, which I hadn’t spotted during the shoot because I’d been concentrating on trying to move the camera as smoothly as possible. I must have slowed down for the later frames.
Anyway, here’s the first frame. The remainder should have been similar but with the image moved slightly under the slit each time.
I wouldn’t say that the test was a complete failure, as it gave me lots to think about. It didn’t however, produce anything like I hoped it would.
I should be clear about how I did this. I wasn’t using the approach where different parts of an image are taken from different frames and are therefore separated by time, leading to peculiar warping effects (which seems to be the basis for most examples available on the web, especially those created through After Effects, Quartz Composer or Processing).
My technique was based entirely on an article by Martin Kelly who used to create slit scans professionally. He describes it as “an extremely simplified form of the highly complex sequences needed for 2001: A Space Odyssey”. The diagrams included in his article show the diagonal smearing of light from the centre of the screen to the edge.
Give or take the adjustments required to line my images up properly, that’s what mine looks like – diagonal smears. They bear no relation to the varied textures visible in 2001. It isn’t just a matter of simple disturbance, described in the short documentary among the DVD extras, because they move smoothly outwards from one frame to the next, so there is continuity.
I’ve already achieved the effect of my analogue approach using Processing, and it would be simple to add random imperfections to simulate the variations in brightness resulting from the low tech, hand-made nature. I can’t see how to leap from this to the Doug Trumbull look though, so I’ve ordered a back issue of Cinefex 85 which has a “comprehensive retrospective” of the film. The magazine is coming from America and will take several weeks to arrive, so I’ll turn to other things in the meantime.
I still haven’t had a chance to compile the brief video clip of my slit scan experiment on Wednesday, but in the meantime, here’s a glimpse of my low-tech rig. Not the extensive use of gaffer tape to hold the plastic box against the enlarger head. Inside the box there are several pieces of thick card to hold the camera roughly in place, and in the base of the box there is a hole cut with a craft knife.
The enlarger head is moved by two wheels at the base of the vertical bracket. It’s not designed for smooth motion, and they wheels are awkward to reach, especially with the light box in the way.
If I use this technique again (and I’m far from certain that I will – to be discussed in another post), I’ll probably experiment with a camera tripod above a smaller light box.
Today I finally got round to experimenting with an analogue slit-scan setup. I’ve started toying with this idea just over a year ago, tinkered with it in Processing, and have been actively preparing for this analogue version for the last few days.
I printed a large abstract image found on the web onto an A4 size transparent sheet, placed it on an A1 size light table, then covered it with a large sheet of dark paper into which I’d cut a narrow slit, just narrower than the width of the image.
I placed all of these under an old photographic enlarger that is securely bolted to the wall in the darkroom at work. I cut a hole in the base of a plastic box for the camera lens to poke through, then used gaffer tape to hold the box against the lens mounting on the enlarger.
Testing the rig proved rather laborious. When the enlarger head was high, I had to stand on a chair to review the test image on the camera’s LCD screen, so a live feed to a laptop would have been useful. In the end, I had the aperture set at f16, started the movement at 50cm above the base of the enlarger and stopped when the enlarger head couldn’t go any lower. Even then, I had to raise the light table on boxes so that the enlarger head finished close enough to the image.
My Heath Robinson rig did what it had to do, but it was far from perfect. The widest part of the lens was too wide to fit through the hole, so I had to take the lens off the camera body when I inserted the camera into the box, then reattach the lens through the hole. This was made even more awkward by having to feed the shutter release cable in between the strips of gaffer tape. As a result, I had to switch off the Auto Power Off setting on the camera as it was too awkward to keep re-waking the camera before each test shot. Furthermore, there no way of fixing the camera in place so that it would slot into exactly the same orientation in the hole in the bottom of the box.
Still, these were merely nuisances rather than serious flaws. I could, if I were going to be using this kit often enough to make it worthwhile, arrange things better and in such a way that the various parts could be locked down to avoid undesired movement.
Even so, there are still too many variables with this approach. One or two might have given it an acceptable hand-made appearance rather than a sterile digital look, but even the few frames I captured differed too much.
As you’d expect, there was no motor to raise or lower the enlarger head, so I had to do it manually. Not only was it difficult to maintain a constant speed of camera movement during each photograph (which led to horizontal bands of brighter and darker patches), but it proved impossible to maintain constant overall exposure for each frame. My hands soon got tired and I slowed down, so the later frames were exposed for longer and were therefore brighter.
There is a more fundamental problem with this whole approach, however. I’m not convinced that this is really how the original slit scans were created, but I’ll leave discussion of that to another blog post. In the meantime, I’ll go away and compile a brief clip of my first attempt.
We went to Biddulph Grange last week, and I took the opportunity to indulge in some (oh all right then, a lot of) photography using my 300mm lens. It’s a long time since I’ve taken more than just a few quick shots, and I found that I was rather rusty, to the extent that I forgot just how short a depth of field that lens has.
In many of the shots, I was using the perspective-flattening characteristics of the lens to concentrate on patterns among the strong geometric shapes of square-cut hedges or alternating light and dark foliage, all emphasised by the contrasts caused by strong, bright sunlight casting deep shadows. On reviewing the results back at home, however, I was disappointed to find that so little of each shot was in focus, and the effect wasn’t as strong as I’d hoped.
Still, that same characteristic worked reasonably well in the shots of flowers.
It may have been true at some stage that the camera never lies, but that time has definitely gone.
Yesterday’s post about kaleidoscopes and light drawings reminded me of these mosaic images of body parts and the Flikr group Camera Toss, where people take photographs with the shutter held open while throwing their cameras around…
Things are starting to look up. I’ve arranged a few activities, including a trip to Edinburgh, and the theatre visit and painting course I booked a while ago are both imminent. I’ve also started thinking once more about my slitscan sketch in Processing.
I watched a brief explanation on DVD of how Doug Turnbull created the slitscan sequences in ’2001 A Space Oddessey’. It turns out that he achieved the mottled effect not by filming the slit itself but by filming its reflection on a roughly textured mirrored cylinder. I realise that this is being pedantic, but since random noise was introduced into the sequence, it’s impossible for anyone, despite their claims, to decode the original images used in the slitscan sequences. These re-creations still have the noise in them.
It would be possible to introduce an equivalent noise to my Processing slitscan sketch, but I’m still keen to try my hand at an analogue version. That will have unavoidably irregular movement of the camera on the vertical axis anyway, which may be sufficient distortion.
Great service today when looking at electro acoustic guitars @PMTCambridge Thanks guys!