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Originally Posted On: https://cam-do.com/blogs/camdo-blog/how-to-determine-your-time-lapse-interval

 

Simply put, a time lapse interval should be set in relation to the speed of the action of what you’re capturing. It determines the length of the final video and to a certain extent, the speed of your final video. And while it’s a fairly simple concept to grasp, it can be a bit tricky to execute, as there are a lot of variables to take into account.

There are a few key items to consider:

• What do you want to capture?
• What is the duration of the event?
• Where will the event take place?
• How long do you want the end video to be?
• How fast is the action taking place?
• Is the action constant or changing?
• Are there any ‘dead’ times where no action will be taking place?

 

What do you want to capture and how long will the event take place? 

First, you need to get clear on the specific event you want to capture. Is it only a sunrise, or a start to finish construction project, or changing seasons, etc. These event examples are very different from each other in terms of scheduling. For example, in a sunrise you will want a more frequent interval to show the movement of the sun. On the other hand, a construction project typically has less consistent action and extends over a much longer period of time. Even then, the different length construction projects will drive a different interval.

 

Where will the event take place? 

To a certain extent, the location of where you shoot also can impact your interval settings, with respect to what kind of power you have available. If you have a way to consistently power your kit (e.g. AC power), then you can take as many images as you’d like, or at least as much as the SD card can hold. However, many long term time lapse shoots we see don’t have permanent AC power available.

To get around this, many people use asolar enclosure, which will provide that consistent power. However, even with this option, you need to ensure you do thenecessary calculations to ensure that your interval is set so that you don’t overuse your power. We often find customers are surprised how spaced out the interval is for construction projects and therefore, they are often surprised that our solar system is adequate for the vast majority of projects.

If these options aren’t available to you, then you will have to use the camera battery only, potentially manually swapping it out throughout your project. And if this is the case, then planning out your interval carefully is crucial.

 

How fast is the action taking place?

Think about how fast the scene is changing. Also, think about how you would like that change to be displayed in the final time lapse compilation. For example, if you have a fast changing scene and you want to record smooth fluid motion then you should set a shorter interval. A slower changing scene can allow a longer interval to still achieve smooth playback. If you want a “jerky” motion, where it looks like things pop from one location to another, use a longer interval in a fast scene.

Depending on what action you’re capturing, you may need to consider using two or more sets of intervals. In the construction example, it may make sense to use the slower interval mentioned above for 95% of the build. And utilize a faster interval to capture rapid/high event items, like demolition or hoisting up framing.

In some cases, such as when scaffolding is being installed on a construction site, you may want a shorter interval for a few weeks, then back to the longer interval when it’s done. Using UpBlink and CloudX Pro gives you this flexibility to adjust simply by logging in online.

Some suggested time lapse intervals for different applications are as follows:

1 second intervals:

• Fast moving weather ie clouds
• Traffic
• Driving

Slightly longer – up to 3 second intervals:

• Slower moving clouds
• Trees in the wind
• Crowds of people
• Sunrise / Sunset

15 – 30 second intervals:

• Moving shadows
• Sun tracking across sky (no clouds)

Longer Intervals:

• Fast growing plants (120 seconds – 600 seconds).
• Stars (15 – 60 seconds)
• Construction projects (15min – 60 mins or longer). Due to the long term nature of construction, different phases happen at different speeds so you might want a 5 min interval as a crane erects structural steel. 60 mins for slow excavation, etc.

 

How long do you want your time-lapse compilation to be, and how long to shoot?

What do you want your end video to be and how will the time lapse footage be used? Is it a standalone video or will it be used as a clip in a larger video?  Also, consider the purpose of your video: is it to monitor a project, illustrate progress, or highlight a project recap from start-to-finish? Understanding these considerations will help you understand the overall interval you need to set.

Think about how many pictures are required to give you the compilation scene length that you want?  If the interval is too short, you won’t have enough frames to make a meaningful compilation. Have you ever seen a 5 second time-lapse? By the time you realize what you are watching, it’s already over. Not very impactful. On the flipside, if the interval is too long, you will end up with many unneeded extra frames to transfer and process. While this is not a big deal, it does take unnecessary time and card/hard-drive space.

We love time lapse videos, but be aware that a long shoot requires a longer interval to avoid making a marathon video length. You can always speed up the frame rate or discard frames, but the key is finding a sweet spot right in the middle. It’s a good idea to slightly overshoot, as you’ll likely end up with many photos you can’t use for various reasons (Inactivity, blockage, lighting issues, weather, etc.). Overshooting will help ensure you have enough usable images to create a time lapse of your desired length that adequately captures your project.

Sometimes you may need a specific length compilation to fit an assignment or a storyboard segment in a larger time-lapse work. Whatever the case, it’s good to do some calculations (which we’ve made easy with ourTime Lapse Calculator).

 

Plan & Test

We harp on this point all of the time. The key to a successful long term time lapse project is planning and testing. It is crucial that this step is part of your workflow every time. Start out with ourTime Lapse Calculator to help understand the right interval to use, and do a test run preferably not at the top of a ladder before the real event. As a rule of thumb, if you are shooting an event for the first time and aren’t really sure what interval to use, it is usually best to use one that is faster than you need rather than slower. You can always speed up too many frames in post but you can’t go back and capture those missing too slow intervals.