Is it possible to be deficient in vitamin d but ok in calcium?

No sun or oral D.: Vitamin d deficiency develops because of inadequate exposure to sunshine and inadequate intake of vitamin d from supplements and food. Over a long period of time calcium deficiency in the bone and blood can develop from significant vitamin d deficiency because calcium can not be absorbed in the intestine.

Different sources: Although calcium(ca) and vit d are sometimes combined in supplements or added together to food, the natural way of obtaining them, and storing them is quite different. Ca comes from dairy foods & dk green veggies, is stored in the bones, vit d is made in sun-exposed skin, and stored in fat tissue. Bones will lose a lot of ca before blood levels drop; fat holds on to vit d.