In our previous thrilling instalment we talked about cameras and briefly talked about settings, but today we’re going to go into a little more detail.
If you are going to capture video that can be used in evidence, we’re going to have to think carefully about how we mount our cameras and how we set them up.
Mounting…
Without word of a lie, there is probably a mount for pretty much any surface, tubing size or body part. The number of accessories just for the GoPro is eye-watering, which makes the choice of where you mount your camera a little more complicated.
You can certainly mount a camera on your handlebars; on your seat post; on your fork; on your head; on your chest or even on the strap of your rucksack or bag. Wherever you choose, there will be a mount you can buy.
However, each location has its strengths and weaknesses. Mounting on your handlebar for example, can transfer the vibrations from the road onto your footage, making for quite a jumpy video, potentially making registration numbers harder to read. However, with good placement and some careful editing, it can prove quite cinematic.
You can also mount onto your head, but that adds weight to an already quite heavy head. You can make things a little easier with a smaller camera like the GoPro Hero Session, but it’s still an additional weight. However, the advantage here is that if you ride by someone driving whilst on their phone at the wheel, you can look right at them whilst also giving them the stink-eye.
Limitations…
I’m writing this in the tail-end of winter. There has been the odd bright, sunny day here and there, but here in Wales the winter is invariably brown, grey and dark. Unfortunately, darkness is not conducive to recording video.
Every digital camera has a sensor, in place of what would have been film going back 20 years ago. Instead of a light-sensitive coating such as Silver Halide there is a grid covered in thousands of rectangular photodetectors and an integrated amplifier.
As with a stills camera, a sensor needs to be hit with enough light to properly expose each frame, but with video there will be at least 24 frames each second! In the film days you would have to change film if you wanted to go from say an ISO100 film to an ISO3200 film, which would allow you to take photos in darker scenes, but with a digital camera it is possible to increase the sensor’s light sensitivity by increasing the amount of voltage going to each photodetector.
Unfortunately, when you increase the amount of voltage (or gain, as they call it), you increase the amount of noise that makes it onto your photo or video. Noise invariably replaces detail, so a noisy image will look a bit muddier. You can see an example of noise from my old Nikon D7000 in the image below. It doesn’t look too bad in black & white, but in colour you’ll often get stray colours popping up from time to time.
The more photodetectors you pack onto a sensor, the more megapixels you’ll have, or the higher the resolution the image will be. However, the downside is that each photodetector will be smaller and will need more gain to properly expose, so potentially more noisy.
Newer digital sensors have improved greatly over the years, but they can only do so much with the light they have available. Meanwhile, back on the bike, particularly in winter you’ll be riding in darkness or at least drab light quite a lot, meaning that you’ll be hard pushed to gather any meaningful footage without a big front light pointing in the same direction as your camera –another benefit to mounting on your handlebars.
Settings…
If trying to decide where to mount your camera wasn’t bad enough, we now need to figure out what settings to use. There will be some trial and error here and you’ll need to figure out which settings produce the best results for you, but there’s some general principles to keep in mind:
4K, 1440p or 1080p?
The greater the resolution of your video, the larger the file size. In practical terms this not only means less recording time at 4K than you’ll get at 1080p, but you’re also going to have to store that file when you get home to your computer. A 64 Gigabyte memory card should give you around two hours of recording time at 4K, so roughly 32GB per hour. They’re big files that your camera may split into a number of smaller files due to file system limitations.
They’re overkill for OperationSnap purposes, but if you want to make ride videos, go right ahead.
Image stabilisation?
Now, this is a tough one. The GoPro Hero 5 Black that I have only has image stabilisation at 1080p, but the newer one has it at 4K. However, if you mount your camera on your bike and you have any part of your bike in the frame, such as a brake lever or your front wheel, you’ll want to be turning stabilisation off. Here’s why…
Image stabilisation will attempt to correct your footage to remove excessive movement, but if you have something in the frame that is always there, stabilisation will start moving that thing around as it attempts to make the rest of the frame smooth, from side to side like a weapon in a first-person video game. Watch my front wheel in this video here:
For me, the video we did at 4K with stabilisation off looked better than this one, even though the light was worse and it was drizzling. Again, your mileage may vary. If you mount your camera to your head, you may be better off leaving it on.
Frame rate
As well as having a choice of resolutions, you’ll also have a choice of frame rates. Movies tend to be shot at 24Hz, TV around 30. However, you may also have the choice of 60Hz or higher.
The higher the frame rate, the more every knock or bump will be captured in your video. Best stick to around 24Hz, unless you’d like to create slow-motion clips in your editing suite of choice.
At 60hz, you can safely slow your footage down in your video editing suite to 24hz to make slow-motion video. At 120hz or higher the slow-motion effect can be greater still. 60hz video played back at 30hz is half-speed; 120hz at 30hz is a quarter –you get the idea.
In part 3…
In our next instalment, Steffan will talk you through OperationSnap, specifically what you need to capture, how you go about submitting your footage and the various do’s and don’ts to keep in mind.
Fortunately part 3 is already written, so you won’t have to wait another few weeks for me to get around to it.
If you have any questions on anything talked about above, or in Part 1, let us know in the comments.
Cardiff By Bike 