Tomato disease - spots on leaves

Late blight has plagued tomatoes across the northeast this season due in large part to the very rainy June and blamed on poor quality tomato starts sold at home stores like Home Depot and Lowes. (These stores don't have the same quality concerns as local nurseries and will sell you any diseased plant they can offload on the unsuspecting!) So when my tomatoes took a turn for the worse back in July, I assumed I was having the same tomato blight problems as the rest of Boston.

Spots first appeared on some lower leaves of a Yellow Girl plant - black spots with white centers and yellow rings. The spotted leaves eventually withered and died and the disease moved up the plant, browning and dying as it went. Then quickly spread to neighboring tomato plants.

Patient Zero - the yellow girl - offered up 6 perfectly beautiful tomatoes before dying completely.

The other affected plants have similarly had no problem yielding delicious, healthy looking tomatoes, even while the plants themselves are slowly browing and dying.

I did what I could - I clipped off the affected portions, pruned heavily to try to lighten the plants and increase air circulation, but the infection continues.

I began to wonder if tomato blight was really my problem when I read that tomato blight produces black, greasy looking spots.

Now I think my problem is either bacterial leaf spot or septoria, but I continue to be puzzled by the fact that the fruit itself doesn't appear to be affected by whatever disease is killing the plants. Despite the problems, we have gotten many pounds of tomatoes out of our six plants. Ironically, the Black Krim Tomato, the single heirloom variety I'm growing, is the one plant that seem to be fending off the disease somewhat successfully.