How a ripe grape berry evolves to an aszú berry?

At which stage do we pick the grape for which wines?

For Disznókő Tokaji Dry Furmint, harvested in whole bunches
Perfectly ripe berry, golden in colour


For Disznókő Tokaji Late Harvest, picked by clusters
Very ripe berry starting to shrivel
First blush of Botrytis cinerea arrives
The blush of Botrytis increases, shrivelling progresses
Botrytis spreads over most of the grape which has gained a purple hint, loss of one third of volume


For Disznókő Tokaji Late Harvest and Disznókő Tokaji Szamorodni wines, picked by clusters
A veil of fungus appears on the skin
Shrivelled to around half of original volume
Intense change in colour shows


For Disznókő Tokaji Szamorodni wines, picked by clusters
Very shrivelled, concentration of sugars and acids advancing
More Botrytis spreads over the skin


For Disznókő Tokaji Aszú wines, a berry by berry selection
Very shrivelled and botrytised berries, dry with intense flavours
The perfect aszú berry - around one fifth of its original weight