Step 5: Clear Away Unexposed Silver Iodide
Once the daguerreotype has finsihed developing, you need to clear away any remaining unexposed silver-halides.
This is the wet part of the process. Under normal room light but not direct sunlight, remove the developed plate from the developing apparatus. The image will have some weird and cool colors to it. As far as I know, you can't preserve these.
Mix 35g of Sodium Thiosulfate (AKA "Hypo") clearing agent with 1000ml water. Pour the solution into a developing tray. Tilt the tray so that half of the tray is dry and place the daguerreotype to be cleared on the dry half. Slowly lower the tray back down to the table letting the hypo gradually coat the plate. You're trying to prevent bubbles from forming here because a bubble will destroy the image. Destroy=bad.
Agitate the clearing agent over the daguerreotype plate and watch as the unexposed purple, blue, and gold particles clear away and you're left with (hopefully) a perfect black and white image on your mirror of silver.
After the image is cleared, transfer the plate from the clearing bath into a bath of distilled water. Make sure that you repeat the part where you ease the water over the plate. Agitate the plate in the distilled water bath for a minute or so and then transfer the plate into a tap water bath. Run tap water into the tray for about three minutes or so to make sure that you've washed all of the chemicals off of the daguerreotype plate.