I believe that it is but doubt that you would notice it for viewing on screen, it is much more apparent in print. I usually (but not always) shoot in raw convert to tiff and edit/crop in tiff and then save in jpeg for web use. A couple of points to consider are that 1 programs such as PSP and PS etc you can alter the level of jpeg compression to suit your needs 2 Some of the high spec cameras jpeg output is almost indistinguishable from tiff unless the image has defined lines but for landscapes I doubt you could tell the difference. Colour definition is better with tiff if there are a vast range of colours in the image

The Truth is Out There