Does multiple day timelapse application for any camera exist?

Question

I'm studying computer science and I'm looking for possible bachelor thesis topics. I was wondering if there is an application for making 24 hour or multiple day timelapses automatically, e.g. program running on computer like raspberry pi will determine ideal exposure for a connected camera based on scene illumination, take pictures by usb, download them from camera etc. It would be open source.

Do you know about something like this that exists?

As an example, I shot this manually: https://www.youtube.com/watch?v=l0Gb9S644qk.

I would like to have a program running on a small computer (raspberry) doing the same.

I like photography and CS, do you think this would be a good topic for a bachelor thesis or complete waste of effort?

Answer 1

What you are trying to do is accomplished by a technique known as bulb ramping, or bramping (see: "What is bulb ramping?"). There are several commercial products and open source projects that bulb ramp cameras to create smooth timelapse sequences without jarring discontinuities in exposure.

Realize that basically, bramping requires prediction, or assumption, about what the lighting conditions will be. In the large, this works well: you know that at sunset, you will predictably have certain rough lighting conditions, on average. What you cannot predict as easily is specific conditions, such as cloudiness that would reduce your exposure more than anticipated.

In my opinion, an interesting bachelor thesis topic would be to incorporate short-term and longer-term weather forecasts to adaptively steer the bramping slope levels. But assuming away weather-induced or other unexpected exposure variations, outdoors timelapse bramping is predictable, and essentially, a solved problem (i.e., probably not an interesting thesis topic).

Answer 2

Here's an alternative approach, which may or may not work depending on just how much the light levels in your scene vary, and how much movement there might be.

Fix your exposure to the minimum exposure you're going to use. Using a simple trigger take a number of shots at each interval in proportion to the light you need. E.g. at noon take one shot at 1/125, after dark take 125 of them and add together for a 1s equivalent exposure.

This could be more or less noisy depending on your noise sources, and I suggest you shoot in raw mode if at all possible to maximise your dynamic range.

You could calibrate the number of frames manually or with a light meter on your control computer (or by image analysis on the fly if you can access the images).