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Dilute the show solution

Sometimes it may be necessary to use a concentrated solution (as in the case of rapid development) and it may be used diluted with water at other times (as in the case of a display in a tank). The degree of dilution of the show solution is affected by each of the following factors:

(a) The duration of the display.
(b) the degree of variance.
(k) Particle size.
(c) The rate of exhaustion of the solution.
(e) The ability of the solution to survive without deterioration.
We talk about each of them below.

First - the effect of diluting the highlighting solution on the exposure time:

By increasing the dilution of the solution, its activity decreases, which calls for the need to increase the exposure time. It is not necessary for the degree of dilution of the solution to be related to the increase in the period of exposure, as some solutions such as (Buffered Fine Grain developers) may be diluted at the rate of one part of the solution to ten parts of water, but diluting them to this degree does not result in an increase in the duration of display by ten times as well. It may not even be more than three times.

When using some other show solutions, the amount of increase in the show time may be related to the degree of dilution of the solution, or at least the correlation is approximate, (such as show solutions with palmitol, hydroquinone, and sodium carbonate), so the show time increases by approximately the percentage of the increase in the dilution of the solution.

As for the sensitive surfaces that remain in the show solution until the show reaches its maximum development to finality, it is noted that increasing the dilution of the solution results in a decrease in the activity of the reduction process in the last stage of show, while the rate of show activity continues to be regular if the solution is more concentrated. That is, the density increases almost uniformly throughout the exposure period. In sum, there is no precise link that determines the relationship between the degree of dilution of any solution and the amount of increase in the exposure time, as this depends on the composition of each solution separately.

Second - the effect of diluting the display solution on the degree of image contrast:
The degree of contrast decreases as the degree of concentration of the solution decreases, and therefore solutions prepared to increase the contrast are often concentrated.

Third - the effect of diluting the show solution on the speed of its exhaustion:
The rate at which the diluted solution wears out is faster than the more concentrated solution, and the permissible degree of dilution depends on the minimum amount of weight of the reducing agent that the solution must carry. There is a high probability that the solution will exhaust as soon as you start working with it, or at least its activity will decrease so much that it is not possible to control the duration of exposure accurately.

Fourth, the effect of diluting the highlighting solution on the particle size:

The fineness of the finer grains increases as the degree of dilution of the solution increases, and this is self-evident, as its activity decreases as the degree of dilution increases. However, it is not desirable in practice to take advantage of this matter, as mitigation is accompanied by a decrease in contrast, as we have presented.

Fifth - the effect of diluting the bleaching agent on the ability of the solution to remain without deterioration:
Transferring the ability of the solution to remain without damage to Keeping Qualities during its storage - if it is diluted, and this is due to the lack of preservatives in it, and for this reason, Stock Solutions are always concentrated, in addition to that they will occupy only a small space in the laboratory.