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Photographic Lighting

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With portable flash there are a wide variety of useful & creative lighting possibilities available. The photographer is able to control the light.
I have two SB600 flash units at my disposal which are capable of being used remotely, as well as a couple of mains powered – daylight balanced fixed lights, various stands, diffusers etc.
The remainder of 6 – Artificial light concerns this type of lighting.
29th Dec 2009, 14:11   comments (0)

6. Artificial Light - Project 54, Outdoors at night

This project simply involved going out at night and shooting city scenes lit by artificial light.
I took this series of pictures from the top of a Norfolk-Line ship as we departed Vlaardingen (Rotterdam) and arrived in Felixstowe.

The floodlit deck shows the Norfolk-Line logo on the ship's smoke-stack (is it still called that?).

Then various shots, using long & short focal length lenses, of the port surroundings.

Using extreme ISO values (6400 in some shots) did, of course, allow me to shoot at higher shutter speeds (from a moving, vibrating ship's deck). There was however an awful lot of digital noise. I made a feature of this in the last image, the close-up of the tug drivers waiting for us to get closer. Converting to Black & White also helps, makes it somehow more acceptable.
29th Dec 2009, 14:02   comments (0)

6. Artificial Light - Project 53, Fluorescent lights

Lighting in public places, places of work, is often fluorescent. Again, the eye compensates much better and sees this light as “white” but it often causes a green wash on uncompensated imagery.
The automatic WB-setting will take care of this, as should manually selecting WB “fluorescent”.

Taking three photographs of various interiors lit by “TL” strips with the WB setting set to:


Produced the following results;

The “Auto” setting has, overall, done a pretty good job of evening out any colour-cast.

The “Daylight” setting has produced a “too warm” look.

The “Fluorescent” setting didn't really help much in any of the rooms photographed. This has probably got to do with modern offices being fitted with Daylight-Balanced lighting.
The camera, set to WB-fluorescent, will apply a Magenta “filter” to counter the (presumed) Green cast. If the lighting has already been corrected to the same colour temperature as natural daylight then there will be a noticeable Magenta-tint to the “corrected” image.

Safe bet would be to fire-off a couple of shots with the camera's WB set to “Auto” and see what the results look like.
Or shoot in RAW and compensate later where necessary, not being “lazy” but fluorescent lighting is different wherever you go and therefore almost impossible to compensate for “universally”.

The other type of artificial light we have talked about is “Vapour” lighting. Street lighting is an example of this, as is stadium lighting. It can vary so much in colour-temp that it can't be generally corrected or compensated, see the situation, adapt.
24th Nov 2009, 16:45   comments (0)

6. Artificial Light - Project 52, Tungsten balance (Part 2)

Candle-light is even redder than light-bulbs. This is because a candle's flame is not as hot as a tungsten light-bulb filament (red being a “cooler” colour than orange or white. Think on the heated iron-bar analogy, first it will glow red, then orange and to yellow as it gets hotter to eventually become “white-hot”, which is a little confusing because we refer to red/orange as “warm” colours and blue/whites as “cooler” colours).
These (bracketed) shots were taken in candle-light. Well, not really, quite a lot of (overcast) daylight was still coming through the window, even after I'd lowered the blind.

The first set of three is with “daylight” WB selected (1824,25,26), the second set of three images with “tungsten” WB set. (1827,28,29)

As is often the case the best exposure option is the one that shows a little more of the surroundings, even if this means burning-out the flame.

The last image (1819), with more of the natural light source in view, has been WB-compensated for tungsten, shows a bit of a blue-cast, but brings out the richness of the flame nicely.
24th Nov 2009, 14:46   comments (0)

6. Artificial Light - Project 52, Tungsten Balance (Part 1)

Photographing a room which is lit by tungsten lights and also daylight through the window can be troublesome.

With the White Balance set first to overcast daylight and then tungsten light produced the effects shown in pictures 1&2

ISO: 100
Shutter speed: 0,7
Aperture: f/4

The “tungsten” WB corrects the orange cast caused by the tungsten light-bulbs but gives an overly blue tint to the daylight coming through the window in the background.
Correcting that blueness in the window area by selecting “overcast” WB throws an unacceptable orange cast over the scene.
A strong enough flash (image 3) will drown out both, but it ain't pretty.
The next series of images are also of rooms lit by tungsten light-bulbs.
First with WB “Overcast”
Then with WB set to “Incandescent” (tungsten) I bracketed the shots by 1-stop over and 1-stop under and chose the best of the three versions.

Settings chosen;

Image 4 (1799)
ISO: 800
Shutter speed: 1/10
Aperture: f/4
WB: overcast
Exposure compensation: 0

Image 5 (1798)
ISO: 800
Shutter speed: 1/10
Aperture: f/4
WB: tungsten
Exposure compensation: 0

These two images are clearly being primarily lit by the light coming through the large window, the single incandescent light in the ceiling is not having much affect at all on the overall scene.

Image 6 (1806)
ISO: 800
Shutter speed: 1/6
WB: overcast
Exposure compensation: 0

Image 7 (1804)
ISO: 800
Shutter speed: 1/3
WB: tungsten
Exposure compensation: +1 stop

This pair are being lit much more by the (incandescent) house-lighting and this is evident in the way image 6 shows the orange cast when daylight WB is selected. In the “correctly” White-Balanced image you can see the reflection of some daylight on the oven doors and how this has been incorrectly compensated, causing it to “blue-out”.

Image 8 (1810)
ISO: 800
Shutter speed: 1/4
Aperture: f/4
WB: overcast
Exposure compensation: +1 stop

Image 9 (1813)
ISO: 800
Shutter speed: 1/4
Aperture: f/4
WB: tungsten
Exposure compensation: +1 stop

The last two shots point directly into the kitchen which means a complete change of light-source again, it being predominantly lit by the large windows. The “daylight” WB was the better of the two in this case.

Where there are two (dominant) light sources in a scene neither one nor the other WB setting will be correct. Other techniques would need to be employed to compensate the colour-cast. Fill-in flash, for instance, could flood-out the incandescent light and is the same temperature (near as dammit) to natural light (overcast). An orange filter over the flash head would make that light source the same temperature as the light-bulbs, evening things out and allowing for WB compensation.
24th Nov 2009, 14:09   comments (2)

6. Artificial Light - Project 51, Tungsten Lights

(viewed 903 times)
The filament inside an “ordinary” household light bulb is made of tungsten. It is made to glow by passing an electric current through it, heating it up to high temperatures.

If we compare the colour of tungsten light with that of natural daylight it is obvious that it is yellow/orange compared to the blue-tint of daylight. Our eyes are very good at adapting to this difference, the camera's CCD sensor, less so.

Using a grey-card I took several light measurements in different parts of a room lit with incandescent light. Even at full-wide aperture settings the shutter speeds required were very low and would prohibit hand-held photography. There was also a huge variation in different parts of the room.

Tungsten lighting is orange in colour, very weak and unevenly distributed.
19th Nov 2009, 08:35   comments (1)

6. Artificial light

(viewed 473 times)
The aim of this section is to become familiar with the particular properties of artificial light, to shoot using photographic lighting and get used to controlling light.

Daylight is much more prevalent in photography than artificial light. Daylight is just “there”, artificial light needs equipment, expertise, preparation.

There are two kinds of artificial light
Available light – found lighting
Photographic lighting – deliberate lighting
Mostly, artificial lighting is weaker than daylight and will require slower shutter speeds and the use of a tripod when using lower ISO settings.

Available light
Found both indoors & out, there are three kinds;
Tungsten light is our household light-bulb
A tungsten filament is heated, creating incandescent light – it is orange in colour.
Fluorescent tubes give off a cool light.
Very powerful vapour lamps vary from the intensive white of a sports stadium to the yellow/orange of some street lighting.
19th Nov 2009, 08:03   comments (1)

Assignment #3: Applying what you've learned so far (part 2)

Image #7
10/20mm zoom @20mm
1/125 sec
ISO 100
This image contains a number of aspects covered so far. There is a triangular shape dominating the frame, red and blue colours contrasting each other nicely and with f/5.6 selected on the wide angle zoom there is sufficient depth of field to keep foreground and subject both in focus.

Image #8
10/20mm zoom @20mm
1/180 sec
ISO 200
Aperture Priority
I was attracted to the shapes here as we walked over the bridge towards Perth railway station.
The curves going all directions, intersected by bold diagonals. Why have a straight wall when you can build a kink in it like that?

Image #9
10/20mm zoom @10mm
¼ sec
ISO 200
Aperture Priority
This was an experiment in slow shutter speeds. A very small aperture selected so as to allow the slow shutter but also to keep the background in focus as well as the structure in the foreground as the commuters hurried past. The blurring giving them a certain sense of urgency.

Image #10
10/20mm zoom @20mm
1 sec
ISO 100
Aperture Priority
This classic view of the Perth skyline was taken at about 5.30am. I had been promised spectacular sunrises over the city. It rained heavily. Grey skies over grey buildings with a grey expanse of water in the foreground. Converting the whole thing to grey-scale made it not a total waste of time getting up so early.

Image #11
10/20mm zoom @10mm
1/2000 sec
ISO 400
Aperture Priority
A view from King's park over the Swan Brewery and South Perth. Apart from the attractive vista it was the complementary orange and blue colours that made me choose this image. I have also discovered that, providing there is plenty of bright light, ISO 400 won't produce any grain and allows for much higher shutter speeds when hand-held like this.

Image #12
18/135mm zoom @135mm
1/125 sec
ISO 400
Aperture Priority
A “Bottle brush” flower, isolated from the background by the use of a relativity large aperture and the longer focal-length. It really was quite busy in the background there with all the various spring flowers stating to display in King's park at that time of year. The harmony in the red/green colour combination adds to the image.
13th Nov 2009, 15:51   comments (3)