The following information accompanied stocks donated to the Bloomington Drosophila Stock Center by the GENIE Project and Loren Looger. The following are a suite of ultra-sensitive calcium sensors termed RSET-jGCaMP8f, RSET-jGCaMP8m, and RSET-jGCaMP8s. These are similar to jGCaMP8f, jGCaMP8m, and jGCaMP8s, respectively (see http://flybase.org/reports/FBrf0249065.htm), with the addition of an RSET leader sequence. The RSET leader improves basal expression and resting fluorescence (compared to the sensor without the RSET leader) while maintaining jGCaMP8 signal-to-noise and response kinetics. For more information, see https://doi.org/10.6084/m9.figshare.26231087.v1. All the insertions are homozygous viable and fertile. P{20XUAS-IVS-RSET-jGCaMP8m}su(Hw)attP8 P{20XUAS-IVS-RSET-jGCaMP8m}su(Hw)attP5 PBac{20XUAS-IVS-RSET-jGCaMP8m}VK00005 P{13XlexAop-IVS-RSET-jGCaMP8m}su(Hw)attP8 P{13XlexAop-IVS-RSET-jGCaMP8m}su(Hw)attP5 PBac{13XlexAop-IVS-RSET-jGCaMP8m}VK00005 P{20XUAS-IVS-RSET-jGCaMP8s}su(Hw)attP8 P{20XUAS-IVS-RSET-jGCaMP8s}su(Hw)attP5 PBac{20XUAS-IVS-RSET-jGCaMP8s}VK00005 P{13XlexAop-IVS-RSET-jGCaMP8s}su(Hw)attP8 P{13XlexAop-IVS-RSET-jGCaMP8s}su(Hw)attP5 PBac{13XlexAop-IVS-RSET-jGCaMP8s}VK00005 P{20XUAS-IVS-RSET-jGCaMP8f}su(Hw)attP8 P{20XUAS-IVS-RSET-jGCaMP8f}su(Hw)attP5 PBac{20XUAS-IVS-RSET-jGCaMP8f}VK00005 P{13XlexAop-IVS-RSET-jGCaMP8f}su(Hw)attP8 P{13XlexAop-IVS-RSET-jGCaMP8f}su(Hw)attP5 PBac{13XlexAop-IVS-RSET-jGCaMP8f}VK00005