It could be alternaria canker which is a fungal problem. Large areas of the leaves between the veins are killed leading to leaf curling and death. Canker can also show up on stems and fruit. I do see spots on the stems as well. The fungus overwinters in the soil. It is important to keep picking off the lower leaves and watering at the base of the plant. The leaves should be bagged and burned. I remove the lowest foot of leaves anyway to prevent splashing and mulch helps.
Tomatoes or any of its relatives should not be planted again in this spot for three years. Alternatively you could try a tomato that is resistant, but it would still be better to change the location.
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Septoria and bacterial spots usually show up as smaller spots and some have a halo of yellow around the spots. Your leaves have large areas of brown/black splotches and it is even on the stems. When I get bacterial speck and septoria, the stems are usually not affected and I pick off leaves early.
Taking off lower leaves of the tomato, providing good air circulation between the plants, mulching and drip watering to reduce splashing helps to control tomato diseases from starting. Once a fungal problem gets in the soil, it is best to change the location until the spore count subsides. There are soil fungicides but they are very expensive and I only used them on ornamental plants. Solarization in July-August will help kill the fungus and bacteria in the soil.