It's not black; it's just a light smoke. You need some sort of darker background to bring out the highlite.
I use 4 oz of plastic as the basis for all my recipies.
If you have some left over; just put the rest in a ziplock and get as much air out of the bag as you can. I've re-used plastic that is months old with no problem. You do have to be careful if you have salt in the plastic and try to keep it for a time as the salt will attract moisture.
Didn't mean to highjack this thread, sorry.
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