I wonder if you could help with my investigations about telephoto lenses? I've often read that 12mm focal length (on m43 sensors) is the low limit for vaguely normal-looking pictures, lower than which human vision and the lens optics diverge substantially. I presume there is a similar point on the telephoto side, beyond which the perspective looks unnatural. If so, is there a commonly-agreed focal length for this limit? My purposes for asking are firstly that I'd like a prime lens that can juxtapose foreground and background objects without the ordinary viewer having a distracting sensation that something strange is going on with the optics; and secondly that I'd like a lens that can 'pump up' flat but interesting land between myself and the horizon, (e.g. a flower-filled meadow) so as to make the flat land more prominent in the photo. Hopefully those uses are compatible? I know that online there are vast numbers of telephoto pics tagged with their focal lengths, but particularly for the second purpose it's difficult to judge accurately the degree of 'lift' without knowing how flat the land was in the first place! I hope to experiment with a range of inexpensive, compact adapted lenses, and having an idea about an 'upper limit' for natural telephoto pictures would greatly help me find a focal length that I'm happy with for these needs. I hope you can help!