I’m not sure why I need to provide a citation to what seems to be a relatively uncontroversial statement. But since you asked:
It is well known in the DSLR community that high frame rate shooting can lead to camera sensor overheating. See this article about Panasonic cameras:
https://www.cined.com/cameras-and-overheating-discussion-with-panasonic/
The laws of physics were not repealed for iPhone cameras. The same issues are at play, with some additional factors leading to the potential for more overheating, namely the small space in which the cameras and their components are situated as well as more processor intensive photo features introduced this year in the new phones.
1500 photos in one day is a huge load on the camera sensor and image signal processor (ISP). That would be over 60 photos an hour or more than 1 per minute if you did nothing for 24 straight hours but take photos. I am assuming that our friend
@Theyayarealiving did not spend 24 straight hours taking one photo per minute, but rather took them in a much shorter time frame (guessing 4-6 hours), many perhaps in burst mode. So that’s 4+ pictures per minute on average for nearly a quarter of a day. And likely more concentrated than that.
If those photos were ProRaw, the burden on the sensor/ISP would be exponentially higher given the tremendous number of pixels being processed and the intensity of the processing.
In my opinion, if the shooting was at that kind of tempo, there’s absolutely no question you could see some artifacts or misprocessed photos. Even more if video was shot as well using Cinematic mode or the stabilization mode.
For giggles, here’s what AI thinks of this issue:
https://www.craft.do/s/atd47RgQf1NTUw