Default DIT & NDIT undesirable? #271
Description
Currently, we have a default value of 1 in the yamls for both exptime, dit and ndit. If a user just wants to run ScopeSim "out of the box", i.e. with a blank .observe(src), the DIT & NDIT take precedence (as discussed elsewhere that in and of itself is a deliberate feature). In the case of e.g. METIS in img_lm mode with a simple point source, this can result in a very suboptimal combination, where the output is only noise. I can attach a notebook showcasing this later.
If we just include exptime by default (at least for packages using AutoExposure like METIS), this should improve, because the AutoExposure can decide for a more optimal DIT & NDIT combination. I don't think there's any particular downside in doing that. In the cases where we want to explicitly set DIT & NDIT, we can still do that in multiple ways.