We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.
Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.
February, 1951
HILLYER, HALLETT AND CARDIFF: STUDIO LIGHTING
49
TABLE I Cost of Operating Spotlights
Lamp Type
Relative
Illumination
f.c.
Operating cost in shillings
Total cost
per hr. for
equal
illumination
Carbons or Bulb
Current
Labour
Total Cost per hr.
MR 170 series ...
100
2.45
4.1
1.75
8.3
8.3
MR 170 parallel
100
3.35
7.85
1.75
12.95
12.95
MR 1450 series
130
2.45
4.1
1.75
8.3
6.4
MR 1450 parallel
280
7.0
11.9
1.75
20. 5
7.35
MR 414 — M.P.
36
3
2.3
0.3
5.6
15.6
MR 414 — C.P.
42
12
2.3
0.3
14.6
34.7
MR 410— M.P.
11
0.4
0.9
0.3
1.6
14.5
MR 410 — C.P.
145
5.7
0.9
0.3
6.9
47.8
MR X 6
1040
53
5.1
The control of the set was, as you have heard, greatly assisted by a meter which indicated directly tne balance of the two " Mole floats.'' A number of meters with 6 in. dials are now available.
The previous speaker stated that he had employed spare arcs for balancing purposes. These, however, require carbons and attention, and arc grids connected in series would be preferable. An automatic balancer has now been produced (Fig. 6) which will automatically switch arc grids in and out to rectify an out-of-balance not exceeding COO amps, on either side.
The effect on location shots will also be great because series-parallel running enables up to 2\ times as much light to be obtained from a given generator. On occasions this will result in considerable economy, but it
will greatly increase the scope of shooting on location, and sets hitherto regarded as impracticable or prohibitively expensive, will come well within the bounds of possibility.
Relative Economy of Light Sources
It is now instructive to consider the relative performance of the several types of lights in regular use.
Table I shows the relative power of the principal types of spotlights, the running cost per lamp, and, in the last column, the running cost for equal light on the set, the M.R. Type 170 150-amp. arc2 being taken a^ the standard. It will be seen that series running has a remarkable effect on the cost of running the 150-amp. arc, but that the M.R. Type 1450 ("The Brute")4 is die most economical light source.
TABLE II Cost of Operating Floodlights
Lamp Type
Relative
Illumination
f.c.
Operating cost in shillings
Total cost
per hr. for
equal
illumiratiori
Carbons or Bulb
Current
Labour
Total Cost per hr.
" Duarc " .
Skypan M.P.
5 kW. Compact Source Single light can .. Double light can
100
200
180
13
31
25
6.0
3.5
0.016
0.032
2.2
2.3
3.8
0.45
0.9
0.45
0.3
0.3
0.3
0.3
5.15 8 6 7.6 0.75 1.2
5.15
4.3
4.2
5.9
3.95