Dried tomatoes vs. dried tomatoes in oil
I would probably substitute roughly by volume. 24 ounces in oil looks to be 2-3 cups, based on my memory of jars I've bought and a quick Google image search to confirm.

But I wouldn't do that with them fully dried - I'd rehydrate them in water or stock (the ones in oil tend to be less thoroughly dried out), and then cram them into your measuring cup (because they're certainly crammed into the jars with oil) and aim for 2-3 cups.

I might also add a tablespoon or two of olive oil to the soup to compensate for what's inevitably in the tomatoes even if patted dry.



I tried to find a good conversion by weight based on nutrition facts (usually works!) but unfortunately sun-dried tomatoes in oil are sold by weight including the oil, but the USDA nutrition facts are for drained tomatoes. For what it's worth, based on a label from a specific brand (found a photo here), the ones in oil are 6/19 carbohydrates by weight (and does seem to be including the oil - it says they're also 5/19 fat), while the USDA says dried without oil are 55.76/100. The carbohydrates are all from the tomatoes, not the oil or any additional water, so that should indicate how much tomato there is.

So: 24 ounces * (6/19) / (55.76/100) = 13.6 ounces. But I'm not terribly confident about that estimate, because it's based on so little evidence, and there's a lot of room for variation here. It's at least in the right ballpark, though - I have about 6 oz of dried tomatoes that look to be about 1.5 cups, depending on how packed they are.