Defects

We can divide defects into these categories:

Phisical defects

Photographic defects

Sound defects

 

Physical defects

We can identify Physical defects with dirt (on the negative or on the print) and scratches, which can be produced before processing (pre-processing scratches), or can be present in the negative, or finally which can be due to processing scratches. As all scratches, they can occur on the emulsion or on the base side.

 Base scratches

 Emulsion scratches

 Dirt

 Preprocessing emulsion scratches

 

Photographic Defects

These are defects concerned with the image on the film. These are:

Image Density

Contrast

Colour

Printing Defects

Grading Defects

One of our main duties in Quality Checking is the approval of the image on the screen for quality. We are looking for an image that is of the correct density, not to light or too dark, with good gradation. Our parameters for this quality are:

  1. Detail in the highlights. The areas that are white should have discernible detail and should not just be white. For example if we are looking at a white shirt we should be able to see detail of folds and buttons and so on.
  2. Detail in the shadows. The areas that are black and approaching black should have detail, for example a black suit should have such details as lapels and pockets discernible.
  3. There should be a good range of tones between white and black.
  4. If the film is colour then the image should have correct colour with the flesh tones right and greys neutral. Obviously some scenes might have a colour balance specified by the director. Knowledge of that particular film is necessary in order to know this information.

With incorrect grading some or all the scenes will be unacceptable with respect to the above criteria.

 

Unsteadiness

Unsteadiness is very easy to see on the screen but rather more difficult to decide whether the print is unsteady or the negative from which the print comes is unsteady or perhaps further back in the duplicating chain.

If we made the print on a step printer where the gate mask produces a frame line, we can get a lot of information by racking the projector so we can see the frame line. We can then see if the image is moving with respect to the frame line. If we made the print from a negative made on a step printer then we should be able to see the negative frame line and again judge if the image is moving with respect to it. If we are able to see the perforations on our projector then we should be able to see the perforations printed from the negative and again observe whether they are moving with respect to our print perforations.

 

Resolution/Focus

Whenever we check a print, which is the result of duplication from archival material, we must be very careful in checking that the duplication process did not introduce any loss of resolution, which might come, for example, from poor focus in the duplication. This can come from poor contact on contact printers, or from excessive slippage in continuous contact printers, or from incorrect focusing on optical printers. We must obviously take into consideration the limitations of photographical qualities of the original materials.

Sound defects

Unfortunately the assessment of sound is rather subjective. The acoustics of the theatre as well as the equipment used affects the sound quality; as, of course, the hearing of the listener affects the perceived quality. This is why if we can view the sound track while we are projecting the film it is of great benefit to us. We can spot a light or dark track and defects such as dirt printed into the sound track area.

Defects of Sound