Neuroglancer clamps values to 8 bit

https://github.com/AllenNeuralDynamics/aind-smartspim-stitch/blob/2493c0b8759d84233346e98985e34092966270e1/code/aind_smartspim_stitch/terastitcher.py#L1005

In the neuroglancer Render tab, changing `#uicontrol invlerp normalized` to `#uicontrol invlerp normalized(clamp=false)` ~vastly~ improves image quality. Is it as simple as making the change here?

Edit: the difference may be more subtle than I initially thought (my own NG ineptitude, haha). I do think it's better though.