BTW, Mark, in the two shots you listed my eye resolves on the center tree as the COI, although much less so in the second one.
Neither of those shots work well in small, one line JPG's. The thing I was working with in the second one was the similarity in the sweep of the raspberry vines and the branches of the trees - but you really need a large image to see that.
Here is a more conventional composition of the first shot, where I decided to try for a COI -
http://www.markcassino.com/temp/agc.jpg
Having thought about this more, I think the eye (or brain to be more
accurate) probably seeks a COI, even if there is an intentional one or not. Just the
way we are scripted. Because we learn to read left to right (or otherwise in
another culture). So our eye tends to scan rectangular graphic images the same
as a page of text. Though the eye tends to go to the center of the image first
I think, unless the COI (maybe a person) is deliberately placed off center and
then it goes there. This, of course, borders on the whole rule of thirds
debate. Let's not go there.
I view a COI as one technique that may or may not be utilized. Just like all those other rules of composition. I wish I could find some examples on the webs, but some (not all) of Elliot Poter's shots have virtually no COI, similarly some of Thomas Struth's nature shots, like his jungle shots, have no clearly defined COI. Here are a few shots I pulled off of a calender by Harry Callahan :
http://www.markcassino.com/temp/scan-010.jpg http://www.markcassino.com/temp/scan-011.jpg http://www.markcassino.com/temp/scan-013.jpg
(I really love that last shot.)
The photography teacher in my last class was big on COIs and where to place
them and what they could be (people, spot of contrasting color, etc). While, as
a former drawer/painter, I had a slightly different perspective -- like
liking lines that run out of the frame, then bring one back in. Dynamic tension. I
feel it's okay for the eye to go out of the frame as long as it is also
brought back in. Because nothing in the frame to engage the eye in some way, no
hook, and the eye will scan right over a picture and find it boring.
Anyway, I am still thinking about the COI thing and still find it interesting food for thought.
I don't reject the idea of a center of interest - I think it can be a really effective compositional tool and use it a lot. It can be particularly useful in advertising photography, where you want a quick, high impact shot (though arguably, those images tend to be of lesser substance.) But I don't think it's a necessity.
Cheers -
MCC
----- Mark Cassino Kalamazoo, MI -----
Photography:
http://www.markcassino.com
