Bramping is a portmanteau of bulb and ramping. It’s a time-lapse where the shutter speed, controlled by an intervalometer, gradually changes over the length of the shoot.
First shot of a time-lapse. Taken at 1/15 of a second, f/8 and ISO 400.
In
situations where the light is gradually changing bramping is a great
way to keep your exposures relatively constant. Sunrises and sunsets are
the perfect opportunity to use this technique. If you don’t adjust your
exposure throughout a time-lapse at sunset, for example, the frames
will become more and more underexposed until they are completely
underexposed and totally black. By gradually lengthening the shutter
speed throughout, you get a far more gradual (and pleasing) transition
from day into night.
Shot taken with the same settings—1/15 of a second, f/8 and ISO 400—an hour later. This is why bramping is used.
Prerequisites
Before continuing with this tutorial, please read my first one on time-lapse and long exposure control with the TriggerTrap mobile dongle. It covers all the basics of the TriggerTrap mobile dongle and TriggerTrap smartphone app (available for both iOS and Android), which I won’t be repeating here.
You
will also need a TriggerTrap dongle, an iOS or Android device to
control it, a tripod and your camera. The technique in this tutorial is
more advanced than a simple time-lapse so you should have some
familiarity with making basic time-lapses before trying bramping. The
other posts in this series are enough to get you started.
Setting Up the Time-Lapse
Bramping
is easier to do at sunset than sunrise: you can set up in daylight
rather than in the dead of night. Get to the location around an hour
before sunset. Depending on where you are and what time of year it is
the speed at which light levels drop changes. If you’re not familiar
with the local area, ask someone who is how fast the sun sets.
Lock
your camera securely down on the tripod and frame your shot. This
step’s important because you don’t want to waste two hours on a poorly
composed time-lapse. The key thing is to think carefully about how the image is framed. Focus where you want in the scene and then switch your lens to manual focus.
For
a time-lapse with a rapidly changing sky it’s usually best to leave
your white balance on auto. The colour light will change dramatically as
the sun sets.
Put your camera in manual mode and dial in your
aperture and ISO settings. The fastest shutter speed TriggerTrap (and
most cameras) can handle for bramping is 1/15 of a second. Some cameras
might not be able to work at that speed, so check and test your
equipment before you head out.
My camera setup for the bramping time-lapse. My iPhone is in the pink bag.
For
time-lapses I like to use an aperture of f/16. For for bramping
time-lapse an aperture that small won’t work as well because of the
transition from light to dark. I find f/8 or f/10 to be the sweet spot
where you still have depth-of-field throughout the scene, especially if you focus using your lens’s hyperfocal distance.
At this setting you but don’t have to crank your ISO too high to
compensate. These are also usually the sharpest f-stops in most lenses.
Set
your shutter speed of 1/15 of a second or slower, and then select an
ISO that produces clean images. For most DSLRs this will be around 400
or so. You don’t want to set your ISO too low; it is the key to well
exposed images after the sun sets. If you want to start with a shutter
speed slower than 1/15 or have a lower ISO you can use a neutral density
filter. Be careful, this will affect the exposure time for the dark
portions of the time-lapse too. Once you’ve found the settings that
produce well exposed frames at 1/15 set the exposure to Bulb.
If
there’s any breeze, hang a heavy bag off the hook that most tripods have
on their centre column. This reduces unwanted vibrations that can
degrade your images. Similarly, if it’s likely to rain either set your
camera up under cover or shelter it with an umbrella, waterproof cover
or plastic bag. Safety first!
Bramping With TriggerTrap
I’m
using TriggerTrap on my iPhone but the process is the same on an
Android device. Connect your phone to the TriggerTrap mobile dongle, and
the dongle to your camera’s remote port.
For the Start shutter
speed select 1/15, or slower if you are using neutral density filters.
For the End value you’ll have to guess. There are no hard and fast rules
on what will work. Any artificial lights will have a dramatic impact on
the exposure, as will light from the moon and the stars. The more light
there’ll be after sunset, the less you need to lower your shutter
speed. I find a value of around 1 or 2 seconds to be fairly safe in most
situations. So long as you shoot in RAW, you’ll still get useable
files. If you’re able to take a test shot the night before in the same
location to work out your final shutter speed, do.
Like with a
regular time-lapse, calculate how long you want your final movie to be.
For most time-lapses I use the cinematic standard of 24 frames per
second. At that rae, for every second of the final video, you’ll need 24
shots. Enter this value in the Exposures section.
Finally, set
the Interval between each shot. This determines the Duration of the
shoot. You need to make sure to set an Interval that’s longer than your
final shutter speed. If you want your time-lapse to cover a set time,
you can calculate that by dividing how long you want it to be by the
number of frames in your final movie. Otherwise, you can just tweak the
value in TriggerTrap until you get a Duration that you’re happy with.
Once
that’s done, push the big Red Button to start and settle in for the
shoot. I always bring my Kindle with me to get a little reading done
while I wait.
The Results
For this time-lapse I took 360 photos over the course of an hour. At
24 frames per second it’s a 14 second movie. The starting shutter speed
was 1/15 of a second and the final one was 2 seconds. All the photos
were taken at f/8 and ISO 400. I started shooting 20 minutes before
sunset but had to restart ten minutes later after a seal destroyed my
shot by drawing a crowd. Yes I had a photo shoot wrecked by a pesky
seal.
Conclusion
Bramping is an great technique for
shooting time-lapses during dynamic light. Many of the most popular
time-lapse videos use bramping to go from shooting a sunset to exposing
for the milky-way. There’s also a lot more that can be done with
bramping using advanced tools and techniques, but the TriggerTrap mobile
dongle is a great way to get started.
If you’ve tried taking a
time-lapse with the TriggerTrap mobile dongle I’d love to see it. If you
haven’t, why not? If you’ve any issues please let me know in the
comments.
