With a rather unusual setup, the SolEx coupled with the IMX 571 wielding Altair Astro 26C camera, I observed a bright solar flare at 2025-09-28 08:43Z (a longer time series actually) at to my surprise, the helium line also lit up. This is not a typical nor a recommended setup of the SolEx. I sacrificed spatial (either way, bad seeing) and spectral (…) resolution for bit depth.

With the Helium image, I cheated a bit: the perpetually changing thin clouds resulted in the helium wavelength’s disk center getting saturated from time to time, so data’s been taken from non-saturated takes, to fill that gap.

He I 5015, continuum-subtracted

Fe II 5018, CLAHE-enhanced signal

spectra, before and during