When the coadd code creates a product with no good pixels (all have effective_exptime = 0.0), the code will throw an exception when trying to calculate the first and last good wavelengths. This sometimes happens for HASP STIS data, but not for Ullyses data as the preprocessing of STIS data takes care of this. To fix, the first and last good wavelengths are set to None if there are no good pixels. The HASP wrapper code detects this and doesn't try to make a product in such a case, but I didn't add a handler to the Ullyses wrapper since the case doesn't occur (and perhaps throwing an exception is preferred to raise visibility to this case).
When the coadd code creates a product with no good pixels (all have effective_exptime = 0.0), the code will throw an exception when trying to calculate the first and last good wavelengths. This sometimes happens for HASP STIS data, but not for Ullyses data as the preprocessing of STIS data takes care of this. To fix, the first and last good wavelengths are set to None if there are no good pixels. The HASP wrapper code detects this and doesn't try to make a product in such a case, but I didn't add a handler to the Ullyses wrapper since the case doesn't occur (and perhaps throwing an exception is preferred to raise visibility to this case).