Getting to Grips with Panned Time Lapse Sequences
As part of a larger mission aiming to bring South African expertise in photography and certain high-end and niche film and commercial techniques to the African commercial market with my colleague, Sean Ackermann (I’ll blog about that soon), we started messing around as almost a side interest at first with time lapse photography.
It was initially never meant to be part of our portfolio, but a quick look at the possibilities such as a look at Dustin Farrell’s or Rob Whitworth’s work and both myself and Sean were instantly hooked.
Achieving the bar set though has been a challenge as the art is certainly a complicated one and to master it takes time, effort and a bit of investment. But in the simple matter of a couple of weeks, we have started to understand and are beginning to get a firm grip on the processes involved. What excites me most at the mo have been the panned sequences achieved (where the camera moves across the time lapse sequence). For the time being, with a simple 2 foot slide and glide we have been experimenting and trying out the medium.
A quick look at the best panned time lapse sequences and what seems to work is a pan along a prominent well-lit or bright foreground subject juxtaposed against a darker background that goes against the main movement (usually sky and clouds) in the time lapse. The other way to achieve great pans, which has been Sean’s realm of interest (I am currently useless with video editing software!) has been to use After Effects to pan and zoom through a static time lapse sequence. We have also been brainstorming some ambitious ideas that will involve some of the lighting techniques we use in photography… but for now back to basics…..
The first thing I will say – is that with the basic equipment that is at our disposal for now – so much can go wrong with even the most basic time lapse sequence. To keep consistency in exposure and white balance throughout all the images you firstly have to set all controls to manual (though even this isn’t enough and I’ll come back to that in a bit). Simply put even a slight jump in the exposure or white balance in 1 or 2 of the images in a sequence becomes obvious to the eye when played back at 25fps later on down the line. Judging exposure becomes a bit tricky if the light changes a lot. The general rule I find is to under-expose by 1 or 2 stops (using an ND filter also helps). If dealing with scenes with massive exposure changes such as sunsets these become very tricky to change exposure incrementally so as not to ruin the sequence. Bulb Ramping (which adjusts exposure incrementally in each consecutive image as the light changes) is the best way to achieve this and can easily be done now with the new firmware for DSLR cameras called Magic Lantern (I am so appalled that the Canon TC-80N3 intervalometer doesn’t have a bulb ramping feature when even the generic makes do).
But even manual settings are not enough as on all DSLR’s they will invariably still adjust the pic exposure and white balance (I never knew this until I started messing with time lapse) for some scenes. This will create the unwanted flicker effect when jumps in exposure occur throughout the time lapse sequence. The best way to get rid of this is with a technique called lens twist (or aperture lock) which effectively cuts communication between the camera and the lens but still allows you to take an image and locks down the aperture. This is done by holding down the depth of field button and lens release and twisting the lens ever so slightly until aperture reading is 00. The downside of course is that you have no control over aperture now throughout the time lapse but it all but eliminates one of the biggest problems with the medium. Mirror lock-up is also another effective method and of course making sure to switch off functions such as Auto Lighting Optmiser and Noise reduction feature.
The other thing that can destroy any time lapse is the slightest movement of frame. Sean has applied the image stabilisation feature in After Effects to good effect on some of the sequences where there was blatant movement, but even this can’t get rid of large movements (wind in Cape Town has been a big problem recently and ruined a few good time lapse sequences). Everything must be dead still for the entire duration of the sequence.
Now adding a panning motion on a slide and glide and things begin to get more and more complicated. Especially as at this point we don’t have a mechanised head. This will change in the next few weeks though. Our first attempts at panning were pretty bad – completely misjudging the number of pans between frames and movement (in mm) that is best for a smooth pan. By trial and error we found that a 2.5mm – 5mm movement between each shot (at around 5sec intervals – anything slower and another flicker effect comes into play) is best.
Now achieving this manually has caused me some serious stress I tell you! Sitting and concentrating sliding a camera along after each shot every 5 seconds exactly 2.5mm takes concentration and when things go wrong (as they invariably do).. there is nothing more deflating than having to start the whole process again!
I am sure we will sit back over a few beers very soon as the mechanised head does its thing and laugh at the days when we used to do the whole thing manually! With time lapse – to avoid agony – it is worth investing in the basic kit but the possibilities are endless – just take a look at what Vincent LaForet is using for his time lapse sequences..
I am excited to take this whole process forward and with the right tools and effort time lapse photography can become an exciting extra dimension to our work.