Pictures taken with long lenses tend to look flatter because we're usually further away.
I think what you're saying is that if you use a wider lens, from the same spot, there has to be other stuff in the picture which contributes to depth. Is that right?But only for the same total final image i.e. the magnification, with the frame covering the same portion of the subject.
If so then consider that the view of first tree is through a hole in a huge white wall, parallel to the sensor. The expanse of white on the print wouldn't help with depth, because it has no depth of its own. If you could see the grass in front of the wall, then it's got the depth back.
The viewing distance of the print, is often, in the words of one our great leaders, misunderestimated. If you look at the print through the taking lens, you get the same perspective.
This pic by Ken Rockwell, with a 13mm lens on 35mm, is so perspectivationally affected that it looks distorted. But fill your computer screen with it, and get your eye close enough, and it all looks right.
If you look at it from too much distation, it's more depthified.
http://www.kenrockwell.com/tech/images/ ... -dubai.jpg
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Not entirely sure what you mean.Surely, the extension is a factor in the viewing position? (I have to admit uncertainty here).
If you take a pic at 1:1 with a 200mm lens, you need to move the sensor 200mm further from the subject, to focus, than you would for infinity.
Yes that DOES have the effect/angle of view you'd normally expect from a 400mm.
Is that what you mean?