>>4095633doesn't look like real noise to me
- consistent throughout the picture, sensor noise you should expect to vary by brightness
- little to no obvious chroma noise, luma noise is more "pleasing", so fake noise tends to prefer that
>>4095718the grid shape you see throughout is due to jpeg compression, jpeg compresses in 16x16 segments called macroblocks, when the compression is too high and/or the image is too hard to compress (noise is the worst case), the macroblock becomes quite inaccurate, and it can become obvious where the edges of them are, as they don't properly blend into surrounding macroblocks, such artifacts are called "macroblocking"
