Brinno Learning Series Part 2 – Choosing a Capture Interval

The essence of time lapse video is the capture interval. This is the single most important setting with any time lapse, regardless of camera. The capture interval is essentially predicting the future. Either you get it right or you don't, if you don't get it right you may not find out until it is too late.

You want balance, too few captures and your video will be too short, too many captures and you will have an editing nightmare. Here are two common wrong scenarios we hear.

Wrong Scenario 1) I want to capture a one year construction project with one picture each day. This will leave you with a tragically short video. Here are the basics, the terms will be expanded upon below. Standard video is played at 30 frames per second (FPS) and there are about 260 working days a year. If you take one picture each day, your final video will only be about nine seconds long. You could slow the footage down but it becomes a slide show, not a time lapse. 

Wrong Scenario 2) I want to capture a one year construction project with one picture every 10 seconds. This will be the editing nightmare. Using the same 260 working days, capturing from 8am-5pm, played back at 30 FPS, your final video footage will be around 8 hours.

Good Scenario) I want to capture a one year construction project, what capture interval do you recommend? If you went with a capture every 10 minutes, your final footage for 260 working days would be 7 minutes long. This is a good starting point, you can edit 7 minutes down to one - three quite easily. There are bad weather days to consider, days with no action, etc. These can all go and you will end up with a nice video.

The first thing we need to consider is how long your final time lapse video should be. We find casual viewers tend to loose interest in videos longer than 2 minutes unless the content is extremely fascinating or engaging. Essentially, the shorter the better for the casual viewer. Someone involved in the project is always willing to watch a longer video, however, if your target is social media, a trade show display, web site, etc. after one or two minutes interest decreases rapidly.

How do we get to the perfect balance? This requires some basic math and the help of the Brinno online calculator. But first, let's discuss playback frame rate. Standard video (TV, movies, etc.) are played at about 30 frames per second (FPS). This is a good speed to play back your videos, any slower and the video lags between frames, becoming more of a sideshow the slower you go. At 30 FPS, for time lapse, 30 captures pass every second. If you capture a frame every second, 30 seconds will pass in one during playback. You can adjust the playback speed within any Brinno camera's settings, we recommend going with 30 FPS and this article relates to 30 FPS.

On to the math fun...

We calculate all of our time intervals based upon the duration of a project. For something short this is easy, 30 minutes for sunset or clouds rolling through the sky. For long term project (three weeks, four months, a year or longer) we like to base our estimate on the number of working hours. Let's go with one year for an example.

There are about 260 working days in a year X 8 hours a day = 2,080 working hours. Now we head over to the Brinno Time Lapse Calculator, which looks like this.



Enter 2,080 into the hours box under Recording Time.
Enter 10 minutes (our educated guess) into the Time Interval.
FPS remains unchanged.
Select Best for the Quality and click Calculate.
The result is a 416 second (7 minute) video which uses only 4.3 GB of card space.

Having extra footage is always better than not enough. Keep in mind, during a year long project, the building structure will be up in much less time. You will also eliminate bad weather days, non-working days, holidays, etc.

Here are a few example interval scenarios...

Suggested Capture Intervals at 30 FPS Playback
Duration	Interval	Video Length
Sunrise/Sunset (30 minutes)	2 Sec	30 Seconds
One hour project	3 SEC	40 Seconds
One day project (8 hours)	10 SEC	1.5 Minutes
Construction one week (5 days, 8 hrs/day)	1 MIN	1.2 Minutes
Construction one month (22 days, 8 hrs/day)	3 MIN*	2 Minutes
Construction four months (88 days, 8 hrs/day)	5 MN	4.5 Minutes
Construction six months (130 days, 8 hrs/day)	10 MIN	3.5 Minutes
Construction eight months (175 days, 8 hrs/day)	10 MIN	4.5 Minutes
Construction one year (260 days, 8 hours/day)	10 MIN	7 Minutes
Construction one year (260 days, 8 hours/day)	1 MIN**	70 Minutes
Construction one year (260 days, 8 hours/day)	1 HR**	1 Minute
* 3 MIN is a CUSTOM time setting 00:03:00 ** Not recommended, for example only

Get familiar with the Brinno calculator, it will take the guesswork out of your project calculations. Play around with the capture interval and if you have any questions regarding your project, please don't hesitate to contact us. We can't stress how important it is to get your capture interval right. If you are second guessing your selection, shoot us an email, info@timelapsecameras.com and we will get back to you the same day.