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.

Test results for Agfa APX 100.

When taking pictures for the test it is best to choose a subject that is evenly lit. This will make the light reading more representative of the whole picture area. Unlike a high contrast view with deep shadows and strong highlights forcing you to take several light readings to find the average setting. It also makes it easer to evaluate the negatives once processed.

The processing of the film went well having spent all morning shuffling developing tanks, measuring jugs and developer bottles, the three strips of film have all been consistently processed. I am very pleased with the density of the negatives, when dry I will do a contact sheet so I can judge how well they will print.

You can see from the picture above, that the 13 minutes development time that digital truths massive dev chart suggests, is spot on. The results also show that you really do need to make a total and utter mess of things before you get a negative that will not print.

The light meter read negative at the centre
of the test strip.

There is a general guide to check whether a film has been correctly exposed and developed it should produce a continuously toned negative. The subjects deepest shadow should be perceptibly heavier than the clear of the film base. The areas that represent the brightest important detail in the negative must not be so dark that you can not read the printed words of a book through them on a sunny day as shown right. Its a quick way of checking to see if your negatives have been correctly developed.

The picture below shows the prints produced by the light meter read negatives in the centre of each of the test strips.

The difference between the top and centre is one and a half stops. bottom and centre is three-quarters of a stop. It is obvious that the longer you develop the less return you get for the time spent. Meaning that you will only get a slight improvement in the quality of your negatives for each minute of extra process time you give them over thirteen minutes.

These tests represent my own personal experiences I strongly encourage each individual to check this film out for themselves. The experiments I have carried out are not exhaustive and should only be used as a starting point.






Related posts:

Sorting out the test strips