when reporting photometric measurements to the AAVSO, if we use a comparison star and a check star, we report the instrumental measurements of the check star, according to the Extended format (KMAG: Instrumental magnitude of the check star. If "ensemble" see example below. If not present, use "na".Limit: 8 characters.). If we perform ENSEMBLE photometry, we report the magnitudes calculated for the check star, (This star's calculated magnitude should be put in the KMAG field, so that if the true magnitude of the check star is found to be different at a later date, a simple zeropoint offset can be added to your ensemble value) . but if we do this correction ourselves, wearing the magnitudes of the target star, What values do we report in the check star? When the values calculated for this are no appropriate to apply a new correction?