Need Control in Afterimage Experiment
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Need Control in Afterimage Experiment
My daughter is doing the experiment on cone cell fatigue and afterimages. She's trying to figure out what would be the control group when doing this experiment. Thanks!
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Re: Need Control in Afterimage Experiment
If you're having trouble understanding what a control is supposed to be, please let me know and I'll give you more information on that. However, I think the main issue here is that it's actually hard to find a real "control" in any part of this experiment. Here are a few suggestions:
Part 1) You could record a "zero second" exposure (meaning you don't look directly at the red circle at all) and then record how long you see the image. This controls for any weird effect caused by just having the red circle in your peripheral vision.
Part 2) You could do a similar control where you don't look at the tri-colored circle at all, but I'd suggest printing a black circle of similar size and using that as a "colorless" control. This is really comparing the recovery rate of rod cells, which are responsible for perceiving black and white, so it's not a true control but it's better than nothing!
Part 3) "Don't look" control and/or black circle control.
Part 1) You could record a "zero second" exposure (meaning you don't look directly at the red circle at all) and then record how long you see the image. This controls for any weird effect caused by just having the red circle in your peripheral vision.
Part 2) You could do a similar control where you don't look at the tri-colored circle at all, but I'd suggest printing a black circle of similar size and using that as a "colorless" control. This is really comparing the recovery rate of rod cells, which are responsible for perceiving black and white, so it's not a true control but it's better than nothing!
Part 3) "Don't look" control and/or black circle control.