A few days ago on TOP, Mike Johnston wrote:
Here's one small way that smartphones are better cameras than other cameras, which no one seems to ever talk about. What if you see—recognize—pictures better on a screen than through a squinty eyepiece viewfinder? ... it's perilous to my ego to consider that I might "see" (compose) better with a flat screen than with a more lifelike and dimensional eyepiece view ... because they tend to "flatten" the scene, that is, make it look more two-dimensional rather than three-dimensional, which (I suspect) aids me in visualizing what the picture will look like as ink on paper.
Ever since I purchased my first Olympus (E-P1) digital camera, I have been using the LCD display as my sole picture making reference. Even with my purhchase of an Olympus OM-D series camera, I still use LCD displays as my primary picture making reference - although, I do use the EVF for fast moving sports (hockey) picturing. I use the LCD display for the very reason Johnston mentions, its flattening effect.
FYI, I should write that, in my commercial picture making life, I spent a lot of time under a focusing cloth, both for my 4x5 and my 8x10 view cameras. In addition, I also spent considerable time looking down onto the viewing / focusing screen of various medium format SLRS. In each case I experienced a heightened awareness - relative to OVF viewing - of a picture's structure (some might say,"composition").
Why is the flattening effect so important to my picture making? The simplest answer is that printed pictures - why make pictures if not for printing them? - are flat 2D objects. And, that intrinsic characteristic (together with my eye and sensibilities) dictates and directs my attention - both in picture making and picture viewing - to a picture's form, i.e. the manner of arranging and coordinating parts for a pleasing or effective result.
Consequently, I perfer the 2D experience, as viewed on an LCD display, in the making of my pictures.
RE: Johnston's statement, "...one small way that smartphones are better cameras than other cameras, which no one seems to ever talk about. iMo, the reason no one talks about the flattening effect of viewing a referent on a display / focusing screen is quite simple ... very few picture makers, even "serious" ones, think of or perceive printed pictures as 2D objects. For most, a picture is a window which allows a viewer to perceive, albeit faux, a 3d world.