Although the Germans seem to be one of the first of the WWI era countries to use a matt finish, it was not on all of their shells. Most examples I have seen have been more of a semi-gloss finish, almost as if you took a gloss finish and then rubbed it most vigorously with steel wool. Paint was applied with brushes on turntables with the shells in the upright position. I know this because I have seen runs in the paint moving vertically. I have examples of the light blue shrapnel shells (77mm) with flat light blue original paint. The color designated "red" in the manuals (for cast iron or early HE shells) is really a flat orange color). These are the only flat colors I have personally seen on WWI German shells. I have examples of Yellow which are of the semi gloss appearance and have two 15cm HE ( Haube shells with original paint), the color listed for these in the manuals as either tan or biege, is in reality a semi gloss very light OD green with a touch of blue. When re-painting WWI German shells, you have to remember that because of the embargo, lots of materials were scarce, paint pigment seems to be one of them. You can see in field eqipment from year to year how the colors change. This happened with artillery shells too. It is not important to get the exact right shade of blue, there really was none. In fact, the color shown on the restoration that started this post off looks perfect to me. I have two examples of original blue paint on 77 gas & HE shells, one is just a tad darker than the one in this post, my other is considerably lighter. One is a Blue Cross shell, the other is the long body HE.