Try this
Last year I was doing a sub freezing test on the Canadian 220w mono. I set the panel out in the drive with a blanket on it so that i could get the meters on it and catch that shock Voc from being suddenly exposed to intense light. The blanket allowed enough light through that the panel was already putting out 20+v but no Isc. It wasn't going to charge a watch battery. There wasn't Isc until after pulling the cover off, having the panel jump to over 40v and then settle back to 38v as it started warming up and producing amps.