First, trust your teacher enough to ask him/her further questions as to how to handle something such as this... Especially if you did not understand what was said the first time.(posted 8388 days ago)You can't 'revive' contrast if you didn't get it in the negative originally when you developed it. You can put some in by intensifying it per your teachers suggestion or by other formulas. Use this as a good learning experience and ask the instructor for a demonstration, personal help or more explanation.