To get good shots of an eclipse you need to use a filter to cut down on the light. I don’t have such a filter, so this is the best I could do [click on image to enlarge]:
The next two photographs are somewhat more interesting, but you wouldn’t know I was photographing an eclipse unless I told you so. They're just photos with a very strong central source of light.
But you may notice a slight twinge of visual pain when looking at those photos. Where does that come from? The retina doesn’t have pain receptors. Mark Changizi has an interesting discussion of visual pain:
The most obvious case is when we look at the sun. And another obvious case is when someone shines a flashlight in our eyes in the dark. In each case we are likely to respond, “Ouch!” From these real-world links between light and pain can we discern what the link may be for?
The example of the sun may coax us into suggesting that it is the retina-scorching amount of light that hurts. However, the fact that the same kind of discomfort occurs when someone shines a flashlight in our eyes shows it is not the intrinsic amount of light that is the source of the pain. A flashlight can be so dim that we can hardly see it in daytime, and yet hurt when shone in our eyes at night. The flashlight’s beam is not scorching anything, although the pain it elicits is every bit as real.
Instead, I suggest that these light/pain phenomena are similar to pain in other domains of our life. The general role of pain is not merely to tell us that something has been damaged, but to motivate us to modify our behavior toward safer or smarter action (and to so without our having to consciously think about it). [...] Our eye fixations are like fingertips, reaching out and touching things in the world; just as fingertips need a pain sense to help optimally guide their behavior, so do our eye fixations. [...]
“Eye pain” of this kind may be the principal unconscious mechanism that keeps us fixating in a smart fashion within our visual field; it is what keeps our eyes performing at their best given our interests at the time. Although this kind of mechanism is unconscious, it by no means needs to be stupid. Instead, it may be able to infer where the brightest parts of the scene are on the basis of global cues in the scene.
For example, look at the earlier photograph of the glaring sun. It feels somewhat discomforting to look at this photograph, and our eyes want to steer clear from the sun. Yet the brightest spot at the center of the sun in the photograph is no brighter than the white elsewhere on this web page which causes us no discomfort to look at. Our brain seems to be able to recognize the sun-glare-like cues in the photograph, and elicits the glare-avoidance pain mechanisms for it but not for the white elsewhere on screen.
Here's an older post inspired by Changizi’s account. In those photos I was shooting directly into the sun, though it was behind a thick cloud cover.
Here’s a photo from the eclipse of 2021, which happened at sunrise on June 10. Notice that the edge of the sun is much sharper:
But then, overall, there would have been less light flooding my camera at that time, which made it easier for me to focus the image.
Finally, here’s a post about the 2017 eclipse where I discuss the problem of pulling a viewable image out of such photos.
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