Originally posted by SuperAkuma In class I've been developing film with a developer that was mixed with water 50/50. The developer is called D-76.
Last week when I developed the Ilford SPX 200 infrared film, the teacher told me to us the developer straight without mixing so I can get a higher contrast. I forgot to ask him if that was something that was just for infrared film or is that a common practice with normal bw film as well.
Generally, developer is diluted for two reasons.
One is to make development times more managable, the other is to decrease grain, though this happens at the expense of acutance.
When diluting developer, the time in solution will increase, and if increased sufficiently, will yield the same contrast as stock developer, but the exposure slope will change, generally showing more mid tone seperations. This is why pictorial photographers tend to use diluted developers, it allows the film to show more detail in the range of zones from 4 to 6, which is where most image detail happens in this type of photography.
Be aware when diluting developer that it is possible to over dilute. You must have the minimun required amount of stock solution in the tank that is required to process the amount of square inches of film in the tank.
As a general rule with inversion agitation type developing, you want the processing time to be at least five minutes to avoid uneven development. With HC:110, I don't think you can get this with dilution A.
It is a good idea with B&W to use a water presoak prior to developing. This removes the antihalation layer from the back of the film, and softens the emulsion somewhat to allow for more even emulsion saturation of the developer. It does require that you extend the processing time somewhat, perhaps 1/2 minute or so to account for the exchange of water to developer from the film emulsion.