Smart Exposure filter is changed to "current" if invalid filter number

[Linwood Ferguson]

I had this happen for real once, but did not understand how, and now I do and can recreate it.

Scenario:

1. Have a template that uses filters 0-6 (or 1-7 or however they are internally, seven of them).
2. Connect a filter wheel with only 6 filters, for example the simulator. This could also happen for a real user with two different size wheels.
3. Drag in a template that uses smart exposure with all filters (0->6, i.e. seven of them).
4. The first six continuing showing the original filter name (correctly). This is true even if the simulator had different filter names, but is probably the correct behavior. However, the seventh filter shows as (current filter), quietly.
5. Assume the user does not notice, maybe was editing some other aspect of the template, and saves that template
6. Later, drag the template in when the full size filter wheel is connected, and it still says (Current filter) and has lost the filter name.

I believe that the proper handling of this is in validating that instruction to show it as invalid (similar to if the filter wheel was not connected), rather than actually changing it. Changing it quietly to current filter is unlikely to ever be the proper answer.

The result of changing it, for me, was that I got a night of imaging with one filter doubled and none for the other filter because I did not notice. This was primarily from experimenting with the simulator, not real life, but someone with a five and seven filter wheel might encounter a similar issue, silently changing the instruction.

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[Stefan B]

Changing this to throw an error will result in some side effects most likely. Some of the “combo” instructions like smart exposure use this instruction internally and then “current” would lead to a failure when used with a OSC camera for example.

[Marc Blank]

For what it’s worth, (I’m pretty sure) the + instructions (Switch Filter +, Smart Exposure +, and the Flat instructions) do what you suggest - they will show an “Undefined” indication in this case.