i know it is keyframable, and its perfect to zoom in. And ive tried testing it with two pictures, one with 50mm focal length and the other is 100mm focal length. after i got the result, i zoom in the 50mm and compare both picture. it seems like both image is the same, meaning using the focal length deteriorate the image quality. or maybe i render both of them with just 10 sample on both picture. Anyway i wasn't sure if i'm right, that's why i'm here. Can you guys confirm my test?