I have a T2i currently and have had it for a while - so I've never really known anything other than that viewfinder - it never had bothered me bc I knew no different. Recently I got on to a film kick and so I bought an A-1 and Olympus OM-1 off CL & ebay and for a few weeks haven't touched my T2i, only been playing with the film cameras. I came back to my T2i for something yesterday and literally thought something was wrong with the viewfinder because it seemed extraordinarily tiny. I quickly realized that my eye had become used to the gigantic viewfinder on the old 35mm cameras (A-1 and OM-1) during those few weeks. And now the T2i seems annoyingly small to look through.
So finally my question - does the 5d3, or really any full frame digital camera, have a viewfinder that is close to the size and awesomeness of the older 35mm cameras?
And followup question - does viewfinder size explicitly correlate to sensor size? Put differently, will a 1.6 crop, such as my T2i, have a 1.6 crop on the viewfinder as well? Or are there other factors in play when it comes to the viewfinder?