Redeveloping the negative.

You will at some point in your developing career, come across a negative(s) that has so much contrast that no matter what you do, you cannot get a decent print. There is a method you can use to retrieve the situation by redeveloping the negative(s).

To start with you will need to make up a solution of halogenizing bleach as follows:

• 10 grams of Potassium permanganate.
• 10 grams of Potassium Bromide.
• 1 litre of cool water.
• Stir this until all is dissolved in the water.

This can be carried out in a normally lit area so you can see the change in the negative. It takes about 5-7 minutes for the black silver on the film to be converted to a yellowish precipitate. You can remove the film from the bleach when the strongest high lights have gone a pale grey and wash well in running water. Now place in a soft compensating developer. When the highlights return to a greyish yellow remove the film and place in an acid stop bath for 30 seconds. Then fix, wash and dry as you would normally. This should produce a softer easier negative to print.

It is probably better to use a farmers reducer which subtracts the density from a

processed negative.They come ready mixed, you only add the right amount of water. This process can be repeated as many times as needed to get the right density; it's not a one shot approach. Allowing you to do a test print at each stage. There are three to types:

• Kodak R-4a is best used for over exposed negatives and is easy to control. Acts on shadows first, then mid-range and then highlights. Mainly used for clearing fog from film and reducing prints.
• Kodak R-4b is best for over developed negatives; it removes equal amounts of deposited silver from the highlight and shadow areas.
• Kodak R-15 This is a super reducer, striping the highlights and not the shadows. For seriously over developed negatives and is the most difficult to control.

This is just a basic outline on the subject and will require further reading.

Evaluating your print test strip.

low contrast

High contrast

correct contrast

Now that you have your test strip what are you looking for? You are looking to see which of the timed sections gives you blacks that are really black without making the whites look grey, with a good separation of the greys in-between. If the picture looks grey overall with no defined blacks then the paper grade is too soft, meaning lack of contrast. On the other hand if the blacks dominate the picture then the grade of paper is to hard - too much contrast! If you need to change the grade of paper you will need to make another test strip. It should be noted that test strip evaluation is best carried out when they are dry as wet ones tend to hold back some of the more subtle grey tones which may encourage you to pull or push the expose time needed. While checking this you should also be ensuring that the focus is accurate.

When your test strip is pin sharp with good clear highlights, defined shadows and the right amount of contrast, you are ready to make a print.

Magnification on your enlarger

This is going to get a bit technical, so bear with me! This is the ratio between the print and the negative. It is calculated using the linear rule. To make things easy, lets say we are going to enlarge a thirty-five mm negative (24 x 36 mm) by a factor of ten this will give us a print size of 240 x 360 millimeters ( about 9" x 14") in size.

Magnification is related to the distance the negative is from the enlarging lens and the lens from the baseboard. So as the latter distance increases the former decreases. In other words the higher the enlarging head is from the baseboard the closer the lens gets to the negative when it is being focused and vice versa. It stands to reason that the larger the print the longer the exposure time will need to be. There will also need to be a change in paper grade to a harder one as there is a softening in the contrast.