there was a question on techinique for tray washing sheet film. I use two trays. Tray on right is under a gentle flow of temperature controlled water. Sheets are moved one at a time from first tray to second tray, the one under the tap. Then first tray is dumped, full tray slid to the left, other tray placed under the tap, and sheets again shifted from left to right, one at a time. This approach is very safe for the film and provides excellent washing because there is good agitation and assured complete changes of water.