1 The Director of Photography – an overview

150 Practical Cinematography
If a scratch shows as a continuous line, then there is probably something
stuck in the light trap of the magazine or possibly one of the layon
rollers in the magazine is not rotating freely. If the magazine
employs felt rollers as part of the light trap, they may need cleaning.
If you are in any doubt as to where the scratching is occurring, run a
second test and before you remove the film from the camera take
the lens out and mark the frame in the gate. Now, when you unload
the film you can count the number of frames before or after the gate
to the point where the scratch starts. If you now mark this point and
reload the camera again with the original marked frame in the gate,
your new mark will be exactly where the scratching is occurring.
You will need to check with the completion bond company as to
whether they wish to hold a developed copy of your scratch tests. If
they do, only shoot them after you are confident your eyeball tests are
absolutely free of scratches and do not run the negative you will be
sending them through a projector, where further scratching may
occur. Simply run an eyeball test on the processed negative to reassure
yourself all is well.
Fog tests
These are rarely carried out unless you are going to a very hot and
sunny country. Point the camera at a wall and write on the wall the
magazine number, then underexpose this by at least one stop to give a
dark grey image on which to look for fogging. Get a strong lamp and
run 20 feet of stock through each magazine while hand-holding the
lamp and pointing its beam at all the joins between the magazine door
and its casing, then do the same for the camera door. On projecting
the print you will quickly see whether any light is getting through
the seals.
With a fog test it is useful to light the room and the magazine number
on the wall with a different coloured light than is hand-held
around the camera and magazine. So if the room and wall are lit by
tungsten light, use an HMI daylight lamp for the test. Conversely,
if the room and wall are lit with daylight, use a tungsten lamp for the
test. This way even the slightest light leakage can be detected as it will
show up as a different colour to the image on the screen.
Lens testing
All the lenses should have been collimated by the hire house before
delivery to you for testing. Should your DP be supplying some or all of
the lenses, then most hire houses will check their collimation free of
charge. Any faults found should be put right before your testing
period starts.
The lens tests that must be carried out are:
● Infinity test
● Resolution test
● Focus tests at various distances.
In addition, as many focus pullers do not trust the engraved scale on
some lenses, they insist on marking up critical focus points on plastic
tape applied around the lens barrel. They will also mark up individual