Standard Lab Practice
Standard Lab Practices
Always, always, always wear safety glasses or goggles when working with chemicals of any kind. You are a photographer. Your eyesight is crucial to the work you do (not to mention just getting around in your daily life). Don't take chances. Wet chemistry can splash and/or spill, and chemical dust can become airborne. Silver nitrate, in particular, will permanently stain organic materials (think skin and eyes!). You may run the risk of blinding yourself if you get it in your eyes. Why take chances?
Nitrile gloves are a good idea whenever you are working in the collodion darkroom. Remember, your skin is porous and you can absorb many of the chemicals you are working with through your hands. Wearing gloves is a good habit to get into, and at the very least it will keep your fingers and nails from picking up silver stains.
Though, not absolutely necessary for all operations, it's not a bad idea to use a respirator if you’re pouring collodion on mammoth plates, or a dust mask when handling dry chemistry that is powdery and can easily become airborne.
For large volumes, pour the liquid into a graduated cylinder then raise the cylinder to eye level to view the surface of the liquid (not the meniscus at the wall of the cylinder) to get an accurate reading of the volume.
For measuring smaller volumes, a graduated syringe provides the most convenient method. Plastic syringes are cheap and relatively easy to get, and an indispensable item to have in your darkroom. To measure out and dispense small amounts of liquid, press the syringe plunger all the way forward, then dip the tip of the syringe in the liquid to be measured and draw back on the plunger until the plunger position is at the appropriate value on the graduated scale.
There are a variety of pocket sized digital scales available at very affordable prices. This is another “must have” for the darkroom. A scale with a range of 500g with 0.1 gram resolution will handle most situations. When using a scale, cover the weighing pan with a square of waxed paper. The paper keeps the scale clean, and also makes it much easier to move the chemicals from the pan to the beaker you’re using.