I'm hoping some more experienced tomato growers will be able to help me identify this problem and suggest some remedies. I have looked at the problem solver site but I'm still not sure if this is early blight. I have 6 tomato plants and so far, 2 of them (big boy and lemon boy) are developing yellow leaves with brown spots. I had a problem with leaf curl that I thought was aphids, but maybe I misdiagnosed? Aside from the yellow foliage, the plants seem healthy and are setting fruit.

I have some pictures posted here: http://dcsprout.blogspot.com

Thanks for any advice you can give me!

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