(40$''$ and 266$''$ wide) imaging slots, with up to 512$''$ in the solar Y-direction.

For this study, a flare successfully observed by EIS must have had at least one raster begin, end, or straddle the GOES start and end times as determined from the routine. If such a raster exists, then all rasters within -30 minutes and +60 minutes of the GOES start and end times, respectively, are returned. The flare location as projected from AIA must have also lain within the EIS field of view. This does not imply that EIS captured any flaring emission; due to the rastering nature of the instrument, the slit may not have been over the flare site at the opportune time. In the example shown in Figure \[sff\_plot\], EIS was running a sequence of $\approx$three-minute rasters (denoted by the vertical green-dotted and dashed ticks) around the peak of the M1.5 flare. The associated regions of the Sun corresponding to each raster are also overlaid on the EUV image as green boxes.

### The Solar Optical Telescope {#sss:sot}

SOT is the first large optical telescope flown in space to observe the Sun. It images sub-full-disk portions of the Sun. Its aperture is 50 cm 