I'm new to this site, so forgive me if I'm posting this in the wrong place, or if it's been answered before, but I'm confused about something regarding DXGI_FORMATs and I figure someone here might know the answer.

When I create render targets (for shadow maps) I use DXGI_FORMAT_R16G16B16A16_UNORM, but when I create my swap chain, I'm passing R8G8B8A8 instead. Anything different fails. Is there a reason that I can't use anything other than DXGI_FORMAT_R8G8B8A8_UNORM to create a swapchain? I can't find any information about it anywhere, so maybe it's obvious and / or I'm doing something wrong.

-Tom