Timelapse enthusiasts call the flawless transition from day to night 'The Holy Grail' due to it's demanding difficulty. This is especially sought after for sunrise and sunset shots. There are a variety of methods out there, each with it’s pro and it’s con. Some are basic and some are more advanced, but are any of them truly the holy grail?
Let's break down the methods we know of:
The most basic, or perhaps “newbie” approach. Just put your camera in full auto (green mode) and go. One important thing to do make sure to cover the eye piece (gaffer’s tape will do the trick) to prevent light from spilling through and affecting the light meter
So what’s the problem with this method? Flicker is the problem! There’s a good chance that the result will have ugly and distracting flickering between frames. Why does this happen? Two reasons; first DSLR cameras are only capable of ⅛ - ⅓ eV granularity between shots and second the light meter is making all the decisions. In the first case this causes ‘exposure steps’ between shots rather than a gradual change in exposure to compensate for changing light conditions. In the second case one could say the light meter is ‘wishy-washy’, zone metering is a wonderful thing in still photographs but with timelapse one moment the meter may lean toward the over-exposed part of the frame and the next moment decide to lean toward the under-exposed side.
There are some software solutions that will reduce or fix flicker, including GBDeFlicker
, GenArts RemoveFlicker
or adjusting the 'CC TimeBlend' filter in After Effects. Unfortunately you may find that these post solutions may not work in every situation. At Dynamic Perception we subscribe to the GIGO philosophy, “Garbage In, Garbage Out”. It's definitely worth exploring some of the more advanced work-flows...
This is a old school method that had its origins in film production. You start either over or under exposed (depending on whether it’s a sunset or sunrise). Then as time goes by the shots will travel through an exposure range. When the shots start moving beyond a certain range, you stop the timelapse, manually readjust your exposure and re-start timelapse. Then in post-production you take your multiple videos, overlap each segment and cross fade between.
This can work in some situations, but the transition may not seem natural when certain variables are in place (such as clouds).
With this method, you shoot using bracketing, as you would for an HDR Timelapse shot. Place each of the brackets into a folder, and from each folder create a video. Take each of those videos and place them in different tracks in After Effects (or similar compositing/editing program). Then fade the opacity across the tracks to keep the footage within a chosen exposure range.
You can get great results with this method, though it can be a time (and CPU) consuming process.
Dramatically bracket an HDR across many stops using a high end DLSR or a product like the Promote Control
Then merge the images into a 32 bit .EXR (HDR) file, this can be done in a variety of ways gingerHDR
comes with a batch merging program, Photomatix also is capable of batch merging brackets to .EXR files.
Use the new Ginger HDR plug-in to do all tone mapping within After Effects.
This is a cutting edge workflow, and currently Jay’s favorite :)
Use the bulb settings on the camera to vary the exposure. Use an external device like the Little Bramper
to control this adjustment (we've heard rumor that the Promote Control will be introducing this capability with a firmware update) .
One drawback is that to date Bulb Ramping only works with Canon DSLR bodies and the other major drawback using bulb mode is the fastest shutter time achievable is 1/30” making very bright to dark situations difficult to achieve without shifting ISO.
UPDATE (Jan 2013): Promote Control now has bulb ramping ability along with ISO shifting making it one of the most sophisticated bulb ramping devices to date. We've tested it with Canon cameras and it's pretty awesome. Not sure if it's working effectively with Nikon bodies due to some interesting issues with using bulb via Nikon bodies where the camera won't do arbitrary exposures.
Software Controlled RampingGBTimelapse
has done a great job of controlling all aspects of Canon cameras to achieve gradual adjustments of exposure over time. Check out the 'Auto Ramping' feature.
The other interesting aspect of GBtimelapse is it's ability to integrate with the Stage Zero system; In these videos you can see how GBTimelapse can work directly with the MX2:
Sample video showing the result of GBTimelapse and MX2 integration:
Again, like Bulb Ramping the drawback is the GBTimelapse software only works with Canons.
There is no “one-size-fits all” Holy Grail. For some users one of these methods might be perfect, but to achieve the ultimate; bright sunlit environment transition to dark skies many of these methods can't quite make the massive shift in EV.
Work flows are always changing and evolving- perhaps someday soon the perfect one will materialize. In the meantime, if you know of some other methods please share those with us in the comments below!