problem is, that i’m unable to write a R16G16B16A16_UNorm at all (as Tiff). this throws:
00:03:23 ERR : SlimDX.Direct3D11.Direct3D11Exception in SlimDX: E_FAIL: An undetermined error occurred (-2147467259)
at SlimDX.Result.Throw[T](Object dataKey, Object dataValue)
at SlimDX.Result.Record[T](Int32 hr, Boolean failed, Object dataKey, Object dataValue)
at SlimDX.Direct3D11.Resource.SaveTextureToFile(DeviceContext context, Resource resource, ImageFileFormat destinationFormat, String desintationFile)
at VVVV.DX11.Nodes.WriterTextureNode.Evaluate(Int32 SpreadMax)
And, when writing a R32G32B32A32_Float as Tiff, which works, the written image is a R8G8B8A8_UNorm though.
So, i guess SaveTextureToFile() converts everything into R8G8B8A8_UNorm. (Also converts R8G8B8A8_UNorm_SRGB to R8G8B8A8_UNorm which also leads to much lighter colours.