Does anyone know what this is? The tomatoes are fine but some of the leaves look like this. I've looked up several things but none match this.

I have one tomato plant whose leaves look just like this. Don't know if it is a disease or a a deficiency of a certain nutrient. I have sent a leaf in for analysis. When the results come in I will let you know. I suspect a nutrient deficiency.

@drsrauch and @gardenfish What variety of tomato plant?

I had one plant this year that looked like that. It was a hybrid called "Patio". I'll be looking forward to your results!

Just got the results back from the U of A agri department. The plant had a bacterial spot, xanthomonas campestris pv. vesicatoria. (what a mouthful!) and a nutrient deficiency. (Type of nutrient not mentioned). The plant was a variety called solar fire, a supposed heat resistant determinate variety. This was the only hybrid plant I have, I usually have all open pollinated and heirloom varieties. I wasn't impressed with the fruit, it had a large white core and a mealy taste, but this could be due to its' problems. This is NOT to say for sure that is what is wrong with your tomato. I think we (as gardeners) spend a lot of time self-diagnosing our plant problems and trying various cures when we would be better off getting an expert diagnosis from a certified horticulturist or someone at a university with a degree in horticulture. I highly recommend that if you have a county extension agent in your town (or close by) that you have him (or her) send a sample in for analysis. Here in Arkansas we have the U of A which is nationally known for their horticulture; they sponsor the county extension service in nearly every county in our state. The county extension service is also responsible for 4-H and the Master Gardeners, of which I am a member.