I have been trying to figure out what samsung is doing with their Camera since the S2.
The S3 was OK, but lacked the low ISO and aperture that the S2 did.
The S4 has 100 ISO minimum and auto usually shoots higher than that, giving you a poorer shot. I have compared hundreds of side-by-side pictures with the S2 / S3 / S4 / S4 Active. And the S2 had by far the best camera. Then S3, then S4, then the Active. However the S4 and S4 active both lacked options for Superfine quality, and you can always see the poor quality in the pictures. I tried hi light, low light, fluorescent, incandescent . . . everything is WORSE on the S4.
If anyone knows any apps that can fix those issues it would be appreciated. I am sure that it has to be some kind of a software / firmware thing in the Camera / Phone. It is 4.1 vs 4.2/3 also . . . so maybe they did something in 4.2 that caused these issues.