The cheapest preservative is your own exhaled breath. Just hold your breath for about 10 seconds to get a higher level of CO2, and then slowly exhale as much as you can into the bottle. The longer you exhale the richer the CO2 concentration will be. CO2 is heavier than oxygen, so as long as the bottle is not moved about it settles onto the surface of the liquid as a kind of floating lid. This way, I've kept stock solutions unspoiled for many times their expected shelf life.
Dark bottles or a dark storage area will help developers, especially if you return used developer to the stock solution which causes a bromide buildup; good for soft highlights, rich shadows and fine grain but apt to darken the developer if exposed to excessive light. Regards, Anthony Farr -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Bob Blakely Sent: Thursday, 27 September 2007 9:33 AM To: Pentax-Discuss Mail List Subject: Developer Turned Black [Was: Sad state of Photo Stores] It would be nice if the bottles had bladders so that they could be capped half used without any air to oxidize the contents. Regards, Bob... -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
