Simone Tranquilli<p>Three images of the solar disk, acquired using three different filters: O-III, Ca-K and the solar ERF, mainly used with the H-Alpha Quark.</p><p>The idea was to compare the results with the simple white light (just the Herschel wedge) and the O-III filter and check for improvements in contrast and details of sunspots and faculae.</p><p>In addition, an image of the central area of the solar disk, with some of the main active regions on those days.</p><p>Follow the link below to see the original mono images in full resolution and read their technical details.</p><p><a href="https://www.localvoid.net/2025/04/20/solar-mosaics-in-different-wavelengths-experimenting-with-filters-25-december-2024/" rel="nofollow noopener noreferrer" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="ellipsis">localvoid.net/2025/04/20/solar</span><span class="invisible">-mosaics-in-different-wavelengths-experimenting-with-filters-25-december-2024/</span></a></p><p><a href="https://astrodon.social/tags/astronomy" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>astronomy</span></a> <a href="https://astrodon.social/tags/astrophotography" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>astrophotography</span></a> <a href="https://astrodon.social/tags/sun" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>sun</span></a> <a href="https://astrodon.social/tags/ca" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>ca</span></a>-k <a href="https://astrodon.social/tags/sunspot" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>sunspot</span></a></p>