Rostrum camera and post-production at Cosgrove Hall

Rostrum camera

There are four rostrum cameras in use at Cosgrove Hall Productions and each one is housed in a separate room, writes David Jefferson.

The cameras can shoot 16 mm and 35 mm depending on the requirements of the production. Most of the television series work such as Dangermouse and Alias the Jester is shot on 16 mm. At the time of our visit they were preparing to shoot tests on the feature film The BFG and had changed to 35 mm.

Rostrum camera base, front view.

The rostrums are computerised to move up or down at the touch of a button. The base moves N/S, E/W and spins with similar ease. Sequences of moves can be fed into the computer which then makes all the calculations necessary for a smooth production.

The cameraman can see exactly what the camera lens does, by viewing a TV monitor at the rear of the rostrum. A particular pan or zoom sequence can be tested by setting it up on the computer and having it run through the moves in real time, while the results are viewed on the monitor. When it comes to shooting that scene the computer will ensure the rostrum is moved the right amount for each frame of film.

The TV image is not recorded onto video tape. It is purely there as an aid to the cameraman.

Rostrum camera base, side view.


Cosgrove Hall have their own post-production facilities on site where the entire editing process is carried out, writes Nigel Rutter.

After recording the dialogue onto magnetic sound film, voice tracks are assembled and cut to the correct length, with due regard to proposed action and pace of the story.

Lip sync breakdowns of the finished dialogue are made, the phonetics being transferred to bar sheets for the animators use.

Following all the production stages of the film, the shot film is assembled and fine cut against the dialogue tracks. Then, after final adjustments are made, the film is ready for the next stage, the final soundtrack preparation.

Extra dialogue, pre-recorded, is added to the voice tracks, which can then be broken down on to as many as three or four separate tracks, since all the voices eventually have to be balanced together with certain sequences requiring reverberation or other effects adding to them.

Sound effects and music are selected, transferred to magnetic sound film, cut against the picture until they all match perfectly. They are added on separate tracks until a rich array of background and spot effects build up a natural framework to the picture.

Again, there may be anything up to a dozen or more sound effects tracks laid up against any particular sequence with at least two music tracks.
The dubbing, or sound mixing, can then be undertaken using outside sound studios. Each piece of dialogue, music and every sound effect is balanced, compressed, reverberated etc as required, producing a composite single soundtrack which matches the pictures in every way.
The picture, meanwhile, is logged and the original negative is cut accurately to the work print. The negative is printed at a film laboratory and adjustments are made to the colour balance of each scene, until a final print is produced with characters and backĀ¬grounds appearing at the correct density and colour throughout the story.

The final picture and soundtrack are matched in synchronism which generally is then transferred to videotape for eventual transmission on television.

Printed in Animator Issue 17 (Autumn 1986)