Amateur Cine World (February 1937)

PRINT COLOUR AND QUAI Ty coloured light in controlling the emotional reactions of an audience. maker at one time also made much use of the same knowledge by showing B ¥y different sequences in a film in different colours. This was accomplished by printing the positive pictures on coloured film base, e.g., deep orange was used for sunsets, red for fires, etc. The habit has died out, not because it was considered wrong as a technique, but because the presence of colour on the film base adversely modulated the sound track. Several attempts were made to avoid this difficulty, either by only partly dyeing the film and leaving the sound track bare, or by using colours which did not affect the sound transmission. In the former case the films were somewhat easily damaged in cleaning, while in the latter case the innocuous colours also proved to be ineffective. Nevertheless, the technique does remain in that many of the news-reels are printed on a lavender base, which imparts a clean, bright look to the pictures without the colour being obvious. Something, in fact, like rinsing white clothes in blue water or putting blue into a pot of whitewash. It is possible to use blue in this way because it has: little or no effect on the sound track. Professional film is projected by means of arc light which is a close approximation in colour to daylight, so that even without the added blue, pictures on the screen will be of a fairly good colour. Even the medium gray passages will appear reasonably neutral. On the other hand, substandard films are almost always projected by means of half-watt light and though the lamps are run at a high temperature, this light is comparatively yellow. The result is that the gray tones, particularly in a low contrast or a high key picture, will often look a foxy brown colour, instead of being a clean neutral tone. The use of blue or lavender overall tinting can give a great deal of improvement in such cases, killing the foxiness and at the same time cleaning up the highlights to give a pearly tone. The user of reversal film can only secure such an effect either by the somewhat troublesome method of dyeing the whole film or sequence in a dye bath, or by employing some Te theatrical producer knows the value of The professional film Foreground interest strengthens the composition and helps to build up an attractive picture. 533 GEORGE Tinted bases often considerably improve the effectiveness of a film: yellow or amber imparts warmth, lavender a cold clarity. And there are other advantages besides the purely pictorial. Amber, for instance, is useful in masking blemishes in a film. He SEWELE, AcR .P:S; sort of filter over the projection lens. The latter method has two disadvantages. One is that if the same filter is used for long periods and subjected to the intense light and heat of projection, it will fade fairly rapidly. If, on the other hand, various coloured filters are required for various sequences, it isextremely difficult to make the change from one to the other at the correct moment and’ colour time-lag from sequence to sequence can be very irritating. There have, however, been a number of colour wheels and other devices placed on the market from time to time. An ingenious friend of mine did design, on paper, an electric relay system in which the next colour to be used was pre-set by the operator on the battery of filters, a notch on the film making the actual change-over. This idea, however, never got beyond the paper stage. The user of negative-positive film can obtain such effects with the minimum of trouble and with practically no additional expense, by simply having his positive prints made on film base of the appropriate colours. Both Ilford and Gevaert, to mention two of the makers of negative-positive, have such stock available and the (Continued on next page)