These could have been 4x5 polaroids, they had pretty good quality, as good if not better than any 35mm or medium format print. As proof point, there was a type

These could have been 4x5 polaroids, they had pretty good quality, as good if not better than any 35mm or medium format print. As proof point, there was a type (50) where you could get a negative as well as a print. I don't recall being concerned about the quality of the negatives, the grain was pretty small. The only downside was the exposure to get a good negative wasn't one where you got a good print. So if it could get a good negative (2000dpi) for enlarging, it can make an awesome print (300-400dpi).