Add just enough water to cover the chopped potatoes in a pan and simmer until they are tender but still firm. Add the corn kernels and simmer for another minute or two.
Meanwhile melt the two tablespoons of butter in a large soup pot and saute the onions until translucent. Add in the tomato paste and the flour and stir for a minute.
Pour in 2 cups of milk and whisk until it's combined. Add in the potatoes, corn, and their water. Add in one of the corn cobs, broken in half.
Season with salt and pepper and paprika and bring up to a simmer. The chowder will have thickened a little bit by now. Add in the salmon chunks and simmer for just a minute, then turn off the heat and cover.
After the chowder has cooled you can refrigerate for several hours or overnight. When you are ready to eat, remove the cobs, bring the chowder back up to a simmer and check the seasonings. At this point I break up the larger chunks of salmon. Add a little more tomato paste if the chowder isn't pink enough for you. Add more milk if it's too thick, and be sure to taste and season well with salt and pepper. Scatter in the chopped fresh dill just before serving.