By nature I measure everything in the metric system, I grew up in a 100% metric society, I was formally trained as a chem. engineer using that system.
powder specific weights, and updatetd those over the years, to make a reliable system.
Nothing like that exists in photo chemicals.
Still a LOT of people uses this system, because they don't know better, don't know the metric system, and because they have some measuring utensils in the house.
I have published in this blog a reliable sytem on how to do this, based on Reinholds recipes on his Blogspot blog.
(CC-M and CC-H is one and the same recipe, the difference being ca 1 gram KBr per litre to control fog levels in the CC-H recipe, since I have ample supplies of KBr, I use CC-H most of the time...)
In a little debate with Reinhold he raised the point of specific weight, even if I think that is moot, I have given it a little thought.
The theory is simple measure out with the meaure, weigh it, and divide by volume, THAT is specific weight. This I have done and reported and reiterated here in this blog.
Yesterday it dawned on me: I took it for granted that the 5ml-marked teaspoon measure was reliable, that it really contained 5ml. But I have never tested that!
OK. Must do that.
Also, since there are many measures around the world, acn anything be said about OTHER measures sold? Definitely, I went on a shopping spree and found two kits of measures here locally.
These seem to be sooper quality chinese brand measures, made from stainless steel, thhe store was Jernia, which is a kitchenware and tools chain over here and these where expensive...
Again I concentrated on the teaspoon marked 1 Tsp 5ml and the tablespoon marked 1 Tbsp 15ml, those are number 2 and 4 from the right respectively.
Aluminium measures (France)
1 Tsp (5ml) : 4,84 ml weight of water = 4,76 gram
1 Tsp (5ml) : 4,78 ml weight of water = 4,69 gram
1 Tsp (5ml) : 4,85 ml weight of water = 4,80 gramMy 3 kits did show marked deviation from what is marked: