This is a thing that's never been explained to me. All diazo emulsions will ship with the little bottle of sensitizer & the instructions for 20 years have said to use a non-metallic paddle or stir stick to stir the sensitizer in to the photo emulsion.
But... as soon as the bubbles settle, we're all pouring it into a metallic scoop coater. I've used a stainless steel spatula to stir my emulsion for years, and if there's been a problem, then I do't know what it is.
Why do emulsion manufacturers still put that in the instructions? What bad thing is supposed to happen if we use a metallic stirrer?
Just one of those little questions in life...
