Your Paglight is excellent when used away from the camera as a modelling light, because it gives you the ability to choose between the PowerArc and a wide range of halogen quick-change plug-in lampholder units. These units can be swapped in seconds, regardless of the lamp being hot or cold. Of course, I must add that great care should be taken when removing a hot lamp and it should be immediately placed into its heat-resistant lamp protector to cool. The Paglight has a full range focusing assembly, giving you the ability to control the beam angle and therefore the intensity of the light and modelling effect.

The Paglight was specifically designed for camera top operation and it fulfils this duty extremely well. When lighting an interview in subdued light conditions, or when supplementing poor daylight with a single light source, it is all too easy to over-light the subject with front light. It is important to use the spot and flood facility in combination with the diffuser, to control the light spread and intensity.

The first light to be positioned should be your modelling light. This will become your key light. As this is the most important light it should be positioned carefully, and this will depend on the scene requirement. Question where the light is supposed to be coming from, and what its source is supposed to be - a window or overhead light? Then decide how much you need to model the features of the subject - the cheekbone, eyebrow, nose, and chin shadows. This should be in sympathy with the subject as well as the story content.

Fig.8 The three light set-up from the left

In a standard set-up the modelling light may be used to simulate light coming from a window, so position this light out of shot, forward of the subject and at window height. When the desired modelling effect has been achieved, the soft fill-light can then be added. This should be placed nearer the lens axis on the opposite side to the modelling light in order to soft light the shadowed areas created by the modelling light. Avoid creating further shadows by over-powering the modelling light effect. When using the spot-to-flood facility of the Paglight in combination with the soft light filter you will achieve the fine control required to balance the effect of these two lighting requirements.
Finally, add the rim or backlight. This can be positioned behind the subject, on the darker side, and high enough to rim light the top of the
head and shoulders. If required, spill light from

When using a combination of artificial and natural light, whether the location is exterior or interior, one or other of these light sources must be colour corrected. However, this does not always apply if the artificial light is being emitted at daylight colour temperature. Examples are some studio fluorescent lights, arc lights, and HMI lights, none of which are incandescent lamps. The exception to this rule is that most industrial and domestic fluorescent tubes will require correction or turning off. If the natural light is strong, and is being used as the key or modelling light, it is important to consider that once filters are added to your artificial lights they may not have enough light output to achieve the desired lighting effect. Also be aware that sunlight is constantly moving, and liable to become masked by buildings, trees or clouds.


Fig.11 The results of setting the white balance to compensate for differing uncorrected light sources.

You should never attempt to use the camera's white balance to compensate for differing light sources. Fig. 11 shows the result of a set-up that comprises a daylight modelling light, fluorescent ambient light and a halogen fill light. The above lighting set-up can produce a green hue with purple in the shadows and this is may not be noticed until the edit stage.

On outside locations most HMI/arc lamps will need little or no correction, but halogen lamps will need to be filtered with a blue or half-blue, dependent upon the amount of colour correction required; this can vary throughout the day.

Imagine that you are shooting a piece to camera (a talking head, as it is often referred to). In a typical exterior set up, if it were a very bright day, you would use the daylight as your modelling light, and your Paglight as a camera-top fill-light. In this situation, you should use the blue Dichroic Filter (Model 9951) in order to raise the colour temperature of the halogen lamp to match daylight. The sacrifice will be a slight loss of light output, but this is preferable to having a colour mismatch. Alternatively, you can use the Paglight PowerArc (Model 9955), which operates at daylight colour temperature without requiring any colour correction. Using the Diffuser (Model
9952) you would then adjust the beam angle to

balance the contrast range between the lit and shadowed areas of the subject.

1. Try not to let the fill-light become the predominant light.
   
   
2. Fill light should always be soft, so it is advisable to use
   the flip-down diffuser, especially in medium to close-up shot situations.
   
   
3. For super-soft lighting use the Softlight Diffuser and Filter Kit (Model 9983).
   This kit works as a stand-alone item, or in conjunction with the Diffuser to give a very flat, super- soft light spread from the larger illumination area. This kit is perfect for medium to tight close-up facial shots.

If you are working inside you can fit gelatine filters to the windows to convert the incoming daylight to artificial light. This would normally be a 204 Full-CT-Orange, a Half 205 or a Quarter 206, dependent on the correction required.
Having done this, the view out through the window will look normal to the camera, provided that the light outside does not overpower the lighting within. If this is likely, measure the difference with a standard light meter and chose a Full-CT-Orange 207 or 208 with + 3 or 6 ND content, reducing light by 1& 2 stops respectively. Filtering in this way enables standard halogen lamps to be used without filters, effectively increasing their output.

Interestingly, any person working within such a room for a reasonable time would gradually become accustomed to the shift in colour and be unaware of this fact until removing the filter from the window or stepping outside, where for a minute or so everything would appear to have a positively blue tint to it, even white sign boards. You would also observe the effect gradually diminishing as the brain readjusted. This is further proof that the human eye can only detect differences in colour content by direct comparison, and this is the reason why the discerning professional uses a colour meter to aid his work.

In any swift set up, where time is limited, filtering windows may not be the most practical solution. The only alternative is to 'blue-up' the tungsten lights with either glass dichroic filters, which can be placed in the filter frame behind the barndoors, or larger gelatine filters. Gelatine filters are cheaper than dichroic but must be set out from the front of any light and away from the heat. The choice is Full-CT-Blue 201, Half CT Blue 202, or a Quarter CT Blue 203.

When using your PowerArc in an artificial light environment you should use the daylight-to-halogen PowerArc Filter (Model 9973). When working closer than two meters from people it is good practice to use the Diffuser (Model 9952). This can also be used in combination with all other correction filters including the larger gelatine Softlight Diffuser & Filter Kit (Model 9983).

Determining the Lighting Requirement on Location

When first entering a room that is going to be the stage for the next set up you have to assess the situation in a number of ways. Let us take the situation illustrated below:

1. The walls are panelled in dark wood
   
   
2. There are two medium-sized windows emitting daylight into the room.
   
   
3. The scenery outside is not worthwhile including.
   
   
4. The ceiling is white suspended tiles with embodied fluorescent down lighters.
   
   
5. The desk is dark wood with green leather inset and a white blotter.
   
   
6. There is a desk top light with an incandescent bulb and green shade.
   
   
7. The floor has a fitted dark red carpet.
   
   
8. There are plenty of power points.

The first thing to decide is the type of lighting required, and part of that decision depends not only on the personality and features of the person in front of the camera, but also on the subject matter of the interview. To create a friendly, appealing atmosphere you should model and fill with soft light. On the other hand, for a hard factual or sales subject you should model with a little harder light and just infill with soft. This technique has the effect of bringing out the facial features that add power and authority to the character.

You must decide if the view through the window should be featured and if the light coming in is useful. Here is a further choice: if the light coming in is not too bright you can 'blue-up' your photographic lights as well as the desk top, if necessary. On the other hand, if it is too bright, you should filter the window using a Full-CT-Orange with a +ND content. Photographic lights can then be used unfiltered, effectively increasing their output.

The fluorescent lights in the ceiling should be filtered, but in this situation it might be preferable to turn them off and then, if required, bounce the camera top light off the white ceiling.
The furniture, carpet and wood panelled walls do not reflect light and therefore do not contribute to the reflected lighting effect. However, they do help when recording sound, as you get better quality without the liveliness of an otherwise empty room.

Going on location with a few carefully chosen yet seemingly non-required bits and pieces will prove invaluable, and may ultimately save the day on one shoot or another. Such things include lighting spigot adaptors, gaff clamps, French flags and magic arms. Down at the bottom of the bag you will have a collection of

chalk, string, wire, gaff tape, camera tape, marker pens, bulldog clips, knives, side cutters, pliers; even an old wire coat hanger, which is a very useful source of strong wire.

One of the most useful accessories is the reflector board used for fill light situations. This can be as simple as a piece of white card or silver foil which has been crumpled, and then flattened and glued to a piece of card or hardboard. For most purposes the size only needs to be about 450mm x 600mm. There are, of course, a number of proprietary makes of reflector boards or materials on the market. There is one such device that has proved to be quite popular because it twist-folds down into a very small space. To open it, you simply pull it from its pouch and shake it. A spring wire loop, seamed into its radius, unfolds with a whoop! Like magic, you have a soft silver fabric material stretched across a hoop, two feet in diameter. The advantage of the reflector material being rigidly suspended or mounted on a flat surface is that you can easily tip it, in order to aim the light exactly where you want it.

What is a Fluorescent Lamp?
A fluorescent lamp is a glass tube within which an electrical discharge is maintained through a cocktail of mercury and various inert gases. The bombarding radiation produces excited atoms and these emit photons as they fall back to ground state.

The closer your light is to the subject, the brighter the illumination will be. The rule is, for a fixed beam angle, when you double the distance the same light is spread over four times the area. This is known as the Inverse Square Law, and it was for this reason that we designed the Paglight with a spot-to-flood facility. This gives you the ability to change the beam angle and recover light that may have been lost outside

In order to establish a standard for defining the colour content of light, temperature is used and quoted in degrees Kelvin. An apocryphal story told to me in the early days of my film career explained that the colour temperature of light was originally derived from a boiling crucible of carefully defined metals, heated to such an extent as to emit a light which matched daylight, as observed at mid-day during mid-summer. The measured temperature at this point was 5600 degrees Kelvin. This was then established as the standard daylight colour temperature. The light emitted from a tungsten halogen lamp would match the light emitted from the crucible of metal when it had cooled to 3200 degrees Kelvin, a domestic tungsten filament lamp would match it at 2700 degrees Kelvin, and so on.

When light sources of varying Kelvin temperatures are being used together, they should be colour corrected as required to conform to a single colour temperature output. In general you will be matching for either daylight at 5600 degrees Kelvin or artificial light at 3200 degrees Kelvin. A range of colour correction filters, are available for this task. A camera balanced for 3200 degrees Kelvin will reproduce images lit by a 5600 degree light source with a blue tint, or conversely a camera balanced for 5600 degrees Kelvin will produce images lit by a 3200 degree light source with an orange tint.

Colour temperature, as defined in a photographic context, is only concerned with the characteristics of the recording medium,