IQ of Panasonic 14-45 f3.5-5.6 vs. Panasonic 12-35 f2.8

Once an image is read into memory from disk, regardless of the format on disk, image processing programs are ignorant of the format on disk. The computer only sees an array of pixels. But every time you save that array to disk, the algorithm to compress to JPEG degrades the image. So don't start with a lossy compression format like JPEG. Saving to JPEG should be the last step of PP, and the last step of PP should be sharpening. I always work with TIF (a lossless disk format) until I'm ready to sharpen. Then I save to JPEG. But anything worth keeping I save the raw file in case I later change my mind or want to do some further experimenting. I don't keep TIF images on my hard disk after I've got an image the way I want it for keeping.

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Frank Paris