Science Buddies: "Ask an Expert"

Hi!
I've already performed an experiment testing the effectiveness of a cysteine protease in the presence of different detergent ingredients (builders, surfactants ect.)
I placed emulsified film strips into different solutions, where the gelatin was broken down and washed off from the film strips at varying degrees. Thus, the film strips each have varying amounts of silver halides (little black dots) still stuck onto them. I want to show that the detergent ingredients did not inhibit the enzyme's ability to break down the gelatin (most of the saliver halide washed off in all cases), except I'm not sure how to present my data.

Is there a way to measure the film strip colour? Opacity? Or would qualitative data be fine (where I describe the reactions)?
Would there be any other way I could quantify my data? Or present it?

Thanks!

Hi,

There is a way to measure the density of a film negative and that is by using the light sensor in the camera on the front of a smart phone. There's an app for this. If your phone is an android here's the URL: https://play.google.com/store/apps/deta ... raph&hl=en

If you have an iphone then check the itunes store: https://itunes.apple.com/us/app/luxmete ... 69821?mt=8

To use the meter for measuring density, open the app and place the phone face up under a lamp. The phone sensor does not have to be that close to the light as long as you get a reading of about 1000 lux. The light reading fluctuates a lot so try to use an app that gives you an average reading of light intensity in lux. To measure the density of a film all you have to do is place it over the camera lens on the front of your phone and record the new reading. The denser the film, the greater the reduction in lux. If your films are really dense you will have to use a more intense light source.

Let me know if this works for you.

Sybee

Hey Sybee!
Thank you so much -- I'll definitely give it a try