Fig. A.3.
Examples of the diverse images included in the considered historical Ca II K archives to show the different atmospheric heights sampled by the various observations. Shown are raw density images from the archives of Ar, Ko, MD, Mi, and MW. The images are saturated to the range of values within the solar disc. The images are not compensated for ephemeris. Unlike in Figs. 1, 3, and 5, the images from the different observatories do not correspond to the same date.
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