Thursday, 19 July 2012

Disaster strikes!

It never rains but it pours does it? And I'm not talking about the weather.

As some of you that follow along with my crazy up and down input to this blog will know...I'm either full steam ahead or full stop!

In the last few weeks I have been quietly working away on the images for Assignment 4 and working through the exercises in this section. I have a few posts half written ready just to upload the images and have even managed to do some of the exercises for section 5 of the course - Narrative. So generally for me - quiet productive.

I have been given an extension for completion of the course until January which I am pleased about as I didn't want to rush !! the final exercises or assignments. So far so good.

Unfortunately it's usually when things are going well that something happens isn't it?

Last week my camera broke. Shutter blew. Only 2 months out of warranty and going to cost several hundred pounds to repair. Not only that it could take up to 2 months for the parts required for repair to arrive from Nikon. So now I'm either borrowing a camera from a friend when needed or trying to pry my old Canon out of my daughters hands to complete some of the images. Neither of which are ideal.

The other down side was that last week I was booked on a photographic workshop with Laurie Campbell - one of  Scotland's leading natural history and landscape photographers. Laurie has several books published, as well as supplying images for Getty Images and the RSPB. He also contributes regularly for Outdoor Photography (UK) Magazine, various other magazines, has appeared in several television programmes and been category winner 3 times in the BBC Wildlife Photographer of the year competition.

Although the weather was miserable it was a really productive day. Armed with a friends Nikon D90 and loads of tips from Laurie I came away with some shots which I am very pleased with. Not only that but I used manual mode in camera all day and have finally got to grips with it. I have been confident using aperture priority mode in camera for some time now but have always been a bit hesitant about switching to manual. It's the usual story that unless someone shows me how to do it properly I always think I'm missing out on a vital piece of information.

The changeable light and weather throughout the day also tied in nicely with the recent exercises I have been doing on exposure and metering, ISO, white balance and colour temperature for this part of the course. 
Red Fox - Manual mode. f/5.6, ISO400 Shutter speed 1/320sec

Eagle Owl - Manual mode - f/9, ISO400, shutter speed 1/1000sec

Sparrow - Manual mode - f/4.5, ISO400, shutter speed 1/800sec

Red Fox - Manual mode - f/5.6, ISO400, shutter speed 1/200sec
Another reason the timing of my camera failing couldn't have been worse is that on Friday July 27th the Pittenweem Arts Festival in Fife starts and runs until Saturday 4th August.

During that week I will be assisting a fellow photographer from the St Andrews Photographic Society - Stan Farrow ARPS EFIAP - in running photography workshops on Abstract Photography. The workshops are fully booked already and there will be an exhibition of the participants images at the end of the festival.

Hopefully a nice friend will lend me a camera - otherwise I just might have to demonstrate how abstract images can be achieved with a pinhole camera i.e. an old cardboard box cobbled together with some sellotape, a roll of 120 film and a pencil as a spool winder! Eek! 

Tuesday, 3 July 2012

Judging Colour Temperature

Exercise -  Part 1 - 3 images Part 2 - 9 images

Part 1
One of the reasons I always shoot images in RAW format is so that I can correct or adjust elements post capture e.g. white balance (WB) or exposure. As I know I can make adjustments later I tend to leave my camera WB setting on "auto". Nine times out of ten I would say the camera records the scene accurately and I leave the image WB as shot.

Reading the course material on colour temperature and around the subject in "Light, Science and Magic"  the subject becomes quite scientific discussing electromagnetic radiation and wavelengths. I think in terms of my photography it's sufficient for me to understand the following:
  • colour temperature is measured on the Kelvin scale.
  • for photographic use daylight is 5500 Kelvin.
  • higher numbers contain more cool colours.e.g. 10,000K light is quite blue.
  • lower numbers err towards red/yellow colours.
The visible wavelengths are the colours of the rainbow with blue wavelengths shorter than red. This is why the sky takes on a red/orange tint at sunset because the short blue wavelengths are more easily scattered in the atmosphere than the longer red which are then more visible. Sunlight at midday is colourless because the full range of visible wavelengths are present.

For the first part of this exercise using a camera WB setting of "daylight" take 3 images,  one in the middle of the day in sunlight, another at the same time in shade and finally another at the end of the day when the sun is close to the horizon. Compare the images.

Image 1
Taken in the middle of the day in bright sunlight this image has high contrast but it appears exactly as I remember the scene.

Image 2
Taken in the shade this image also initially appeared to represent the scene as I recall it at the time. Comparing it to the image above afterwards I would say it appears cooler than the "neutral" white balance I remembered.

Image 3
Taken at the end of the day.
(image to follow)

I am expecting the image taken at the end of the day to have a warmer WB than the others which is a result of the light reflected from the sky. The image taken in the shade has less contrast than the full sun image and also a slightly cooler tone.

The camera records the differences in these circumstances quite distinctly and much more than our eyes do as they adjust to the variations in light very quickly. Being aware of the way the camera's WB setting can affect an image when combined with the actual light at the time is another important tool for a photographer to learn to use.

The second part of this exercise is to take a series of pictures but in this case adjust the WB in camera. So in each set of 3 below, one has been taken in auto WB, another sunlight/daylight and the third WB shade.
Compare the images.

Series 1

In this first set of three the auto WB image at the top is closest to my recollection of the colours at the time. The sunlight WB is acceptable but the shade WB image is far too yellow and the colours are unrealistic.

Series 2

In this second series of images it is more difficult to differentiate between the auto WB and the sunlight WB. This is probably because of the variety of deeply saturated colours in the scene which would make either image acceptable. Of the two I prefer the sunlight WB (centre) as the colours of the white flowers are more realistic. Again the shade WB is too yellow.

Series 3

I think it is in this final series of three images that you can see the effect of changing the camera's WB most clearly. The auto WB has recorded the scene quite accurately. The sunlight WB has an overall blue tone and the shade WB has a yellow tone. In this case auto and shade WB are more accurate.

Comparing the results of this exercise has demonstrated how selecting the WB to suit the conditions at the time is important. Selecting the incorrect WB can result in quite a strong colour cast. However it is always possible there may be some creative decision behind using an "incorrect" WB. Generally the auto WB setting does a reasonable job. However I will continue to shoot in RAW format so that I can make adjustments later for the following reasons.

Personally I find reviewing an image in camera difficult. The size of the LCD screen for starters makes it impossible to view colours in any detail and when out in the field the images will be viewed in the ambient lighting conditions which will also have an effect on how it appears. Shooting in RAW format means that I have full creative control over the images.

Although I would be reluctant to rely solely on in camera WB settings, through comparing the results of this exercise, have a better understanding of why it is something to be considered at the time of shooting. 

Measuring Exposure - Part 1

Exercise - 4-6 photographs

For this exercise I have to produce between 4 and 6 images which are deliberately lighter or darker than average and explain why.

Image 1
In this image the subject and background are both light in colour. I deliberately exposed the image so that there were no harsh shadows as I wanted the image to have a soft ethereal feel to it. To help soften any shadows the subject was photographed in a light tent to diffuse the lighting. When photographing light subjects its easy for the camera to underexpose and render the background darker than it actually is. In this case spot metering was used so only a slight +EV value was required.

shutter speed 1/4sec, f/5.6, ISO100

Image 2
This is a high key black and white image of my nephew. It was taken in natural window light with a white reflector used to fill any shadow areas. Matrix metering was used and the camera flash suppressed to avoid any overexposed areas in the image.
shutter speed 1/60sec, f/4, ISO700
 Both of these images were exposed deliberately lighter than average which is confirmed by studying the histograms which are heavily weighted to the right indicating that the majority of the tones within the images are lighter than mid grey.

Image 3
shutter speed 1/160sec, f/9. ISO400
This is an example of an image which is deliberately darker than average. In order to maintain the saturated colours and overall mood of the image I used spot metering in this instance.
Image 4
shutter speed 1/1250sec, f/6.3, ISO200
This image is also darker than average. The subject is relatively bright in contrast to the darker background. Matrix metering was used in this instance and has captured the contrast in the scene well without any further adjustment in exposure being required.