Other possibile modes are target and exposure modes. If no context is selected in advance, then the results of operating on tools could be applied to existing visits or exposures. We discussed whether exposures could be created outside the context of an visit. The idea here is that templates could be created that hold information about an exposure. But these exposures will not be used until they are applied to some visit.
Users can update existing template values.
They could use a set values in one template to copy into another template. We felt it would be dangerous to allow users to define their our templates because it would not be clear what the implications would be to a proposal. We asked whether visits are a universal concept or are HST-specific. It is not clear how the ETC would handle pos-targs, since the ETC might compute counts based on the reference target, rather than the actual target in the aperture. So when the VTT positions are based on pos-targs, the ETC may not get the appropriate target that is actually intended.