You might also consider the combination of using the albumen for photography and the egg yolks for cooking. This is an excerpt from James Reilly's "The Albumen and Salted Paper Book":

What can you do with the yolks of your eggs? Make them into cheesecakes that will be pronounced unrivalled. Dissolve a quarter of a pound of butter in a basin placed on the hob, stir in a quarter pound of pounded lump sugar, and beat well together; then add the yolks of three eggs that have previously been well beaten; beat up all together thoroughly; throw in half of a grated nutmeg and a pinch of salt, stir, and lastly add the juice of two fine-flavored lemons and the rind of one lemon that has been peeled very thin; beat up all together, thoroughly, and pour into a dish lined with puff-paste, and bake for about twenty minutes. This is one of the pleasantest "bye-products" we are acquainted with in the economics of manufacturing photography. Try it!

IIRC, Suda House had another recipe for a custard in her "Artistic Photographic Processes" book.