Quote Originally Posted by Len Middleton View Post
Large format is just abound with opportunities to screw up images, including:
Pulling the wrong darkslide resulting in an exposure through the ground glass.

For tray processing of two or more sheets, have a look at the "slosher" method. Plenty of posts here and elsewhere on the internet, so a simple search will turn up enough of them to keep you busy for a while.. Alternatives are the BTZS tubes, Arkay/Doran paper safes (modified with a slosher), and the Paterson Orbital.