"GIANT SUNSPOT: There's a big dark spot in the middle of the sun. David J Kriegler saw it last night at sunset over Gulf Shores, Alabama:
This is AR3190, one of the largest sunspots of surging Solar Cycle 25. "It's almost five times the diameter of Earth, and could be seen through the thick humid atmosphere over the Gulf of Mexico," says Kriegler.
The scale of AR3190 makes it an easy target for amateur astronomers. You don't even need a solar telescope. Eclipse glasses work, too. You might have some old ones left over from 2017; if not, here's where you can get a new pair.
Caution: Sunset photos like Kriegler's are possible, but be careful. Even when the sun is dimmed by low clouds or haze, looking directly through the camera can damage your eyes. Always use the LCD screen for viewfinding.
Thanks for posting this. Large groups of sunspots and occasionally individual large spots have been viewed without optical aid by different cultures for over a millennium. There is also a famous medieval drawing that you can read about here: https://sunearthday.nasa.gov/2006/locations/firstdrawing.php
As noted in the article, if you have eclipse glasses laying around from 2017 you can use those - much safer than looking through clouds at sunset (please don't do that). If you don't have eclipse glasses, if you use a solar filter, you should be inspecting it every time you solar observe, including holding it up and looking at the sun through it with just your eye. This is a great opportunity to see if you can see large spots without additional optical aid.
I would like to…
I would like to study Giant Sunspots for the last 1,000 years
Not sure, giant sunspots has been reported in the past and officially recorded.
I have 3D polarized lenses - glasses ( horizontal vs. vertical) and plan to test if polarization can work as solar filter
Please do not post about unsafe solar observing practices here in the forum. The AAVSO is not responsible for any injury you cause to yourself; to be perfectly clear, the AAVSO does NOT sanction, approve, or suggest that anyone "experiment" with original techniques of solar observing. Period. We post information on approved techniques in the AAVSO Solar Observing manual. https://www.aavso.org/sites/default/files/publications_files/solar_guide/Solar%20Observing%20Guide-V1.1.pdf
Proper solar filtering is not just in the visible band but IR and UV as well. As you can see in the following discussion, IR is NOT blocked effectively when using polarizing filters that seem to block sufficient visible light: https://solarchatforum.com/viewtopic.php?t=28776
thank you for the link
I risk nothing if I mount solar polaryzer filter to $10 web camera, coming with IR filter by default