A Presentation by Alan Moss for Aberdare Camera Club LIGHTING

Transcription

1 A Presentation by Alan Moss for Aberdare Camera Club LIGHTING

2 Colour Temperature Colour temperature is expressed in degrees Kelvin and the effect this has is to give a colour cast ranging from red through to blue. The human brain automatically compensates for this effect and so we see white as white in all but the most extreme lighting conditions. The camera uses the White Balance to deal with this problem or, in the case of film, different film and the use of coloured filters. The main advantage of Digital Cameras is the ability to adjust the White balance to suit the lighting, either at the time of shooting or, if you shoot in RAW, at the time of processing the image.

3 Colour Temperature 1,700 K Match flame 1,850 K Candle flame 2,700 3,300 K Incandescent light bulb 3,400 K Studio lamps, photofloods, etc. 3,800 K Quartz Halogen Studio Lamps 4,100 K Moonlight, xenon arc lamp 5,000 K Horizon daylight (Morning or evening) 5,500 6,500 K Typical overcast daylight, electronic flash and daylight corrected lights. These temperatures are merely characteristic; considerable variation may be present.

4 Lighting Control The Inverse Square Law Inverse Square Law The amount of light falling on a given subject area is inversely proportional to the square of the distance from the light source The inverse square law applies with all lighting

5 Types of Lighting Daylight Incandescent Daylight corrected Flash (strobe)

6 Daylight Outdoors Overcast is the best as it gives a soft diffused light. Sunshine can produce very harsh shadows so you will need to use a reflector or fill in flash to soften the shadows Windows Again shadows may be a problem so a reflector may need to be used Overhead If the light is diffused then it is almost ideal but shadows will be apparent, particularly under the nose and chin, so a reflector should be used below the subject.

7 Incandescent Light Tungsten Halogen Very good light You see the effect of the light Very hot (has been known to set things on fire) unpleasant for the model Not daylight corrected Expensive to run Very good light You see the effect of the light Again very hot Not daylight corrected Expensive to run

8 Incandescent Lights Halogen Incandescent Light Tungsten Panel Fan Cooled Tungsten Fan Cooled Tungsten and Daylight Correction Filter

9 Daylight Corrected HMI (Hydrargyrum Medium-arc Iodide) Developed for TV and the movies Very expensive to buy and to run Not absolutely daylight but close enough Daylight corrected Fluorescent and Energy saving Reasonably cheap to buy Cheap to run Cool Running Bulky Limited range of lighting modifiers

10 HMI (Hydrargyrum Medium-arc Iodide) & Fluorescent Panel Lights HMI Lights Fluorescent Lights Ballasts to run the HMI Lights

11 Various Low Energy Daylight Corrected Lights

12 Flash Small Camera Based Flash Highly portable Integrated to camera metering Can be used off the camera Quite expensive if you want multiple heads Studio Flash Offers powerful flash Many Light Modifiers available Can be very cost effective Bulky and not very portable

13 How does flash work Guide Number and Watt Seconds Flash Power: A guide number of 40 metres at ISO 100 means that a target 10 metres away will be correctly illuminated with an aperture of f/4 (40 divided by 10 = 4) using a sensitivity of ISO 100. Studio flash units are usually quoted in watt seconds and there is no direct correlation between this and guide number. (confusing eh!!!!) Scientifically speaking 1 watt second is equal to 1 Joule Watts-seconds figures are to be seen as logarithmic, meaning that between 2400 and 1200 there is one stop light difference. A picture taken at f/11 at 1200 watts-seconds would require only f/16 at 2400 watts-seconds. Conversely 600 Watts-second would force you to open to f/8, 300WS f/5.6 and so on.

14 How does flash work Flash Power: Flash Power Control: Small Camera Based Flash The intensity of the flash does not change The duration does from around 1/50,000 of a sec. To about 1/1,000 of a sec. Flash Power Control: Studio Flash Unlike small flash, with studio flash the actual output power alters. This has a minimal effect on the duration of the flash (typically around 1/1000 sec).

15 Flash Synchronization First Curtain Sync. Second Curtain Sync. High Speed Sync.

16 First Curtain Sync.

17 Second Curtain Sync.

18 High Speed Sync.

19 FIRST CURTAIN SYNC Direction of rotation Anti Clockwise

20 SECOND CURTAIN SYNC Direction of rotation Anti Clockwise

21 HIGH SPEED SYNC SYNC Direction of rotation Anti Clockwise

22 Incorrect Shutter speed Shutter speed set at 1/500

23 Types of Flash Equipment Camera Manufacturers Dedicated Flash 3 rd 3 rd Party rd Party Dedicated Dedicated Flash Flash Hammerhead Hammerhead Flash Flash

24 Types of Flash Equipment Dedicated Ring Flash Macro Twinlight Ring flash Adapter

25 Types of Flash Equipment Bowens Semi Pro Flash Bowens Pro Flash Elinchrom Flash

26 Types of Flash Equipment Ring Flash Ring Flash Adapter

27 Light Modifiers Snoot Spill Kill Reflectors & Barn Doors Beauty Dish Softbox Honeycomb Fresnel Spotlight Adaptor

28 Positioning of Lights & Reflectors

29 Positioning of Lights & Reflectors

30 Positioning of Lights & Reflectors

31 Positioning of Lights & Reflectors

32 Positioning of Lights & Reflectors

33 Positioning of Lights & Reflectors

34 Positioning of Lights & Reflectors

35 Useful Contacts Karlu Photographic - Suppliers of a wide range of studio equipment. Viewfinder Photography - Again they have a wide range and the staff are very helpful. Prices are generally very competitive. First Call http.// Very often the cheapest for similar or identical items. Totally reliable. I have bought virtually all my equipment for my studio from these three suppliers. Generally they deliver within 2 days.

36 Best Book I Have Found on the Subject The Complete Guide to Light & Lighting in Digital Photography By: Michael Freeman Published By: ILEX