Science Buddies: "Ask an Expert"

I am doing a modification of "Bioluminescence: Investigating Glow-in-the-Dark Dinoflagellates" experiment and I need to measure how much light small tubes of dinoflagellates produce. I want to create a brightness scale and measure the brightness based on that, but it seems rather qualitative, not quantitative. I do not want to spend money on a light emission device or anything. How do I go about doing this? Does anyone have advise on how to create a brightness scale? I read something about taking a picture and analyzing the data from pixels in the picture on a Adobe Photoshop type place but I haven't been able to find instructions on how to do that. Any advise would be greatly appreciated.

Hi - I am sorry that you did not receive a reply more quickly.

As you noted, the project does set up a qualitative scale for assessing brightness. Searching the forums, another thread came up with a similar question, and the comments might be helpful for you: viewtopic.php?t=11206

One thing you might want to consider is Google's free Science Journal app. One of the sensors in the app is a light sensor. You would have to experiment to see if it would be able to help you measure your samples, but I would suggest giving it a try. We have not tried the app with this project, and there is a chance that the light given off will not be significant enough to be recorded with the app. There is another project that uses the light sensor in a similar way, and in that project, the app only worked for measuring on iOS. (The light sensor works a bit differently on iOS and Android.)

If you have an iOS device to use, you may want to try it and see what happens. We would recommend reading the other project and the notes on using the app for that project: https://www.sciencebuddies.org/science- ... #procedure

We have a tutorial for using the Science Journal app to measure and record data. The first two posts are about learning to use the app in general, and then there is a post specifically about the light sensor. You can reach all of these posts here: https://www.sciencebuddies.org/blog/science-journal-app

If you try the Science Journal app with this project, we would be really interested in hearing about your experience and in seeing the data you record with the app!

Amy
Science Buddies