another sound film sighting...

[rollemfilm]

it will be a hard sell to convince me that Super8Sound does not have the tooling to load 50ft carts. they have a major international super8 industry!

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[#Pedro]

dsavetsky:

Pan focus problems:
Everytime, when you project a film which only has a main stripe and no balance stripe with a projector with a very fast lens (1:1,1 etc), AND the projector has a gate construction with the pressure plate located at the side of the lens, you may have pan focus problems.
The pressure plate presses the film towards the gate. Between film and gate there is only one sound stripe at one side of the film. So the film surface gets automatically tilted in horizontal direction. With 2 soundstripes it get in parallel again.

If the projector has the other gate construction (like most reg 8 machines), pressure plate at the side of the lamp and gate at the side of the lens, the film is pressed towards its emulsion side and material thickness or soundstripes don?t matter any more.
But there are only a few models made with this genial gate construction (Beaulieu, Heutier, Braun Visacustic, others?).

So, problems in pan focus are not related to the Beaulieu magazine, but to the projector construction. Striping afterwards the balance stripe will avoid any problem.
And: only with fast quality lenses, you can see the problem, as these lenses don?t have any depth of field.


The Beaulieu mags had a long developing time, as the construction and camera modifications involved are quite complicated.
One main problem was light invasion from outside, eihter into the mag itself, or into the daylight spools.
Another problem was the compatibility to special effect options of the cameras. Therefore ONLY Beaulieu cameras can be adapted to the mag, atempts with Nizo had been abandoned after one year of try and error.

The camera modification involves diferent aspects:

1. control and supply of the two winding motors.
The camera will be equippted with an additional printed board, covering the whole top area of the body. This board contains the fwd-rew control of the mag motors as well as the adaption do the differnt speeds. The electrical connection is made with a special socket over the viewfinder.

2. coupling of the sprocket drive.
The mag contains a central sprocket drive, that pulls the film from the supplying reel and takes the tension away from the capstan drive, caused by the take up reel. So it is creating two film loops, like any 16 mm camera.
This sprocket must run absolutly in sync with the claw. The coupling therefore is made directly, mechanically.

In the centre of the original friction disc of the camera, they put an additional reel that is directly connected to the main reel of the camera. The mag connects to this reel in the centre of the friction.

3. fine-tuning of colimnation and mechanical tolerances, to optimize focus and registration and avoid any light invasion.


After the conversion, the camera takes standard 50 ft carts as well as the mag. The carts are driven by the friction disc of the camera, and the mag by the mid reel in the centre of the friction.

I have a camera body with this conversions, but no mag. I prefered to invest my money in a better lens and not in the mag. The camera becomes VERY heavy and you need always a triplet for serious shooting. The film is far more expensive that the same length in 50 ft carts. If I ever will get involved in feature film making, I will get a mag, but now I am happy with 50 ft carts.

Pedro

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