The concentration of water soluble developers SHALL be measured by taking specific gravity hydrometer readings.
Note that the water soluble developer solution does not require agitation. There are a wide variety of materials
available to formulate water soluble developers; therefore, the specific gravity hydrometer readings versus concentration
will vary more than they will for the wet suspended developers. Figure 1-8 shows the concentration range (between the
lines) for several water soluble developers of one manufacturer; others may even be above or below the lines. The
supplier can provide an accurate conversion chart for its particular developer, which SHALL be used when checking
the developer concentration.