Measuring chemicals in powder form - how?

[haris]

And if anyone need to measure small amount of powder chemicals, there is one great solution. In stores which supply schools you can buy precise measurment gadgets which are used for chemistry or physics classes. I think that is best solution. And as those are school items, they shouldn't be expencive too. Or if not schools suplier, ask in you closest pharmacy store...

 

[vet173]

I bought one of those small electronic scales, but found the platform to small for weights with larger volumes. I now use a dial-a-agram. As PE stated there is only one way to do it right and that is to weigh it. I ask my dealer how com extol is not available in smaller packages and it was his understanding that the small package could not be weight consistant in smaller quanitys on a production basis.

 

[David A. Goldfarb]

I have a small scale with a small platform. For small quantities, I just measure onto a slip of paper on the platform. For larger quantities, I use a plastic or paper cup. Electronic scales usually have a button that allow you to zero the scale to subtract the weight of the container.

The only anti-fogging step you must take is to ensure that your darkroom light levels are sufficiently low. (This includes light leaks, safelight levels, and control of stray light sources, like cordless phones that might light up when a call comes in.) As I understand it, anti-fog compounds in developers are mainly used to control age-related fogging in paper that's old or that's been improperly stored. It's not something you'd normally need to be concerned with when just starting out, unless maybe you've inherited a bunch of "mystery paper."

In theory, some say that if you require a restrainer or an antifoggant in a developer, then you need to reduce the accellerant or the alkali. In practice, this is often not the case, because no amount of base fog is tolerable in prints and some paper/developer combinations start to become foggy in the highlights before they reach Dmax in the shadows, so it would be normal to use some benzotriazole or KBr to correct this situation.

 

[Gerald Koch]

As I understand it, anti-fog compounds in developers are mainly used to control age-related fogging in paper that's old or that's been improperly stored. It's not something you'd normally need to be concerned with when just starting out, unless maybe you've inherited a bunch of "mystery paper."

Benzotriazole and potassium bromide can also be used to change the image tone of prints. When added to the print developer benzotriazole shifts the tone toward cooler values and bromide shifts toward warmer tones. By using both in the correct amounts you can achieve a pure neutral black.

 

[srs5694]

Benzotriazole and potassium bromide can also be used to change the image tone of prints.

Yes, but Bruce (the OP) is already suffering from information overload. He seems to need advice on what advice to ignore, and uses for benzotriazole or other antifoggants is one such type of advice, at least for the moment.