I hardly ever shoot into the sun because the exposure will contain so much latitude that parts of your photo will inevitably end up being blown out.
As a rule, you expose for the highlights, so you could say that the photo below is overexposed. I don't like it because of that, but I included it in the selection for this story because quite often a photo editor might like a photo you don't, as happened here.
In the top picture, however, which is taken about five minutes later, I have cropped out the sun with a long lens so I can expose for the whole frame. I use manual exposure all the time. Never use auto, especially when shooting into the sun. In the top photo, I have exposed for the highlights and you get a lovely silhouette.
Shooting into the sun will show up any dust on your lens or sensor but with modern self-cleaning sensors that is not such a problem. Normally, at the end of every day I do go over my gear with a blower brush and have a look at it. But I am not a real clean freak unless something really dastardly happens. You might be surprised to see the state of my cameras.
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