I consider Amalfi and Ravello much better for photography overall, and Positano highly overrated for most everything. While it's beautiful, the best Positano shots are from a distance, either a mile or so down the road, or from way up in the hills, as well as some nice views from the ferry from Amalfi to Positano.
In Amalfi, don't miss the cathedral. It's stunning, inside and outside, although it can get very crowded on the steps. Wander the narrow streets and enjoy some limoncello, gelato, or other local specialties. If time permits, and you don't mind an easy to moderate hike, check out the Valle dei Mulini or Valle della Ferriere, which offer great views of tens of thousands of lemon trees covering the terraced mountainsides. Or visit Pogerola and Pontone, small hamlets in the mountains above Amalfi, for spectacular views. Also check out Atrani, a tiny village just a 20 minute walk from the heart of Amalfi. In Ravello, go to Villa Rufolo for their wonderful gardens, and of course the most famous view of the entire Amalfi coast.
Since your time is limited, consider hiring a driver in Amalfi for the day to take you along the coast, from Positano to Ravello, stopping at your convenience (drivers also know the best photo spots); otherwise, you'll be limited by the ferry and bus schedules.
In Sorrento, I think Marina Grande offers the best photos, but wandering the streets can be fun too, stopping periodically to taste homemade limoncello. There are also some nice views from along the road just outside town. If time permits, take the ferry to Capri for gorgeous views everywhere, and perhaps take a boat ride to the Blue Grotto.
I spent a week in Amalfi last October and the weather was excellent. I hope you get the same.
Check out this link for my photos from 2022:
https://www.flickr.com/photos/leaningladder/albums/72177720304965663