I'm surprised that you haven't taken shots in situations where the rear screen can't be seen clearly. I hate the things for that reason especially as I suspect the problem is down to back lighting - lap tops don't have the same degree of problem but if cameras were brighter in this area I suppose the battery life would be shortened. Mobile phones can handle this aspect automatically so cameras could too. Some seem to like turning that off.
Olympus had a neat idea on Pen's. Anything that could be shown on the rear screen could also be seen in the viewfinder. Great but they dropped it on the dslr like type cameras. On the other hand on the one I am using currently a preview pops up in the viewfinder with a small square showing the best focus point so I have no need to check. Tough if I don't use enough dof. To check that I have to use the rear screen but could do it with a bit of difficulty via the viewfinder on a Pen.
Maybe some dslr rear screens are better than others in this respect. I've used a number of viewfinderless compacts and all have had this problem.
John
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