Figure 2.

Transmission spectra of the four excitation filters (interrupted lines) and the single multiband emission filter (solid lines; see text for details). Numbers 1–4 relate to excitation filters 1–4 described in Methods. V_m and [Ca²⁺]_i indicate emission-filter wavelength bands used to detect di-4-ANBDQPQ and fura-2 signals (short wavelength band of emission filter was not used). For information on dye emission spectra, see Matiukas et al²⁷ (di-4-ANBDQPQ) and Grynkiewicz et al²² (fura-2). Curves showing filter characteristics compiled from Chroma Technology and Semrock catalogue data.