Figure 2.

Brightness and interplane distance calibration. (a) Normalized average intensity of image planes in the green channel as a function of axial scan position (scan step equals to 100 nm). Solid lines represent Gaussian fits, and crosses (camera 1) and open circles (camera 2) are measured data. (b) Linear fits of z-scan positions of intensity maxima as a function of image for each color channel. These fits give an interplane distance of 355 ± 24 nm (mean ± standard deviation of seven sequential inter-plane distance measurements) for the green channel, 361 ± 41 nm for the orange channel, and 372 ± 71 nm for the deep red channel.