Fig. 5
The OptoArm allows manual intensity adjustments, which modulate biological readouts. A To record worms in an inexpensive way, we used a Carson smartphone adapter to place and orient a cellphone camera to a microscope. A blue light filter was placed between the ocular and sample to avoid interference of the blue light with recording. B Schematic of the experimental outline: a priori determined intensities (0.2, 0.4, 0.8., 1.2., 1.6, and 1.8 mW/mm2) were set by adjusting the resistance of the potentiometer. At the different intensities, the ∆body length was measured. C The histograms show the distribution of intensity readings at a priori-specified intensities. Red lines show the average intensity. D Smoothened histograms of C that show the increase in intensity when adjusting the resistance of the potentiometer. E Pictures of a D1 worms (myo-3p::ChR2::YFP) just before and during illumination with 1.6 mW/mm2 blue light. Scale bar: 200 μm. F The different body lengths (normalized to length before illumination) at different intensities of illumination with the OptoArm. Calculated via a midline approach, n = 10