Just playing a bit with some magnets, iron filings, and a piece of paper. I’ve wanted to take a few shots of this practical experiment for some years now. Finally I had the inspiration to do it..
All shots are negatives of the originals, since to my eyes, the magnetic field lines show better this way.
And a comparison of some homemade magnetic field lines and the aspect of some sunspot groups in H-alpha light. Note the similarities. They might not be the best examples, but they are my only ones showing similar structures on the Sun.
maximus photography 
Hi maximus! I love these visual representations of magnetic fields! I was thinking of experimenting with this and was wondering what type of magnets you used? How strong do they need to be? Also, I’m curious just how big these were.
Great work, hope I will hear back from you!
François
Hello François! Glad you like the magnetic art stuff 🙂 Unfortunately I don t remember the magnets very well, they were a one time deal, but they were about 50 mm long, 5 mm thick and about 10 mm or so wide. They were the type used in education for children, with red/blue ends. Not too powerful as they were not Neodymium ones. I think at the edge they were 50-100 or so mTesla. A Neodymum one would be around 300 or so mT…but they are a bit impractical for such use in my opinion.
Max