Using a polarising filter (35)

Requirement

x images

Purpose

To understand the role of the polarising filter and how to use it to greatest effect

Technical learning

 

How polarising works

• Polarising light typically darkens clear sky, improves the tonal quality of foliage and makes water surfaces more transparent.
• Unpolarised light vibrates in all directions in a plane at right angles to its direction of travel. When light is reflected from a non-metallic surface, it will be partially polarised, i.e. the wavelengths will be more constrained to one direction in the plane at right angles to the direction of travel
• The Polariser does its work by removing glare and so enhancing colour saturation and contrast,  i.e. it screens out light which is not vibrating in a single direction. 
• The effect works best when the camera is at right angles to the sun and requires rotation to fine tune the polarising effect

Ancillary effects to note

• Polarisers reduce the level of light entering the camera between 1/3rd and 3 stops (depending on the strength of filtration). Consequently, shutter speeds will be slower unless adjusted by dialling up the ISO setting. 
• Polarisers work most evenly with standard or moderate telephoto lenses. The breadth of the wide angle lens results in uneven distribution of the effect of reducing glare.

Exercise instructions

Part 1 - Skyscape

Set-up

• Pick a clear or partially clear sunny day
• Work when the sun is relatively low in the sky (e.g. mid morning or mid afternoon in spring or autumn)
• Select a viewpoint with a 360 degree aspect
• Use a tripod, standard or moderate telephoto lens and a polarising filter
• Frame a view that is at 90 degrees to the sun with a significant part of clear sky
• Rotate the filter to establish the lightest and darkest treatment of the sky

Images - standard or moderate telephoto

• Shoot the brightest and darkest compositions 
• Re-compose image so that the sun is directly behind the camera and shoot

Images - wide angle lens

• Shoot at the darkest setting

Review

• Examine impact between brightest and darkest rendering of the sky using the standard/ moderate telephoto
• Compare the darkest (standard/ moderate telephoto) with the darkest (wide angle): is the first more even than the second?

Part 1 - Water scene

Set up

• Pick a relatively bright day
• Select a scene with water  (e.g. a river, lake, etc) with items immediately below the water line (e.g. rocks)
• Aim the camera at the water at the same angle at which the sun strikes the water  (e.g. 30 to 40 degrees) 
• Rotate the filter so as to maximise and then minimise the reflections seen through the viewfinder

Images

• Take a pair of polarised and unpolarised images of the water

Images and review

Waterscape -  Virginia Water

 

Polarised - rocks beneath water become clearer

Unpolarised

 

Skyscape - Beach at Burnham-on-Sea at low tide

 

Polarised
Stronger definition of clouds, more intense
blues

 

Unpolarised
 

Using a grad filter (34)

Requirement

x images

Purpose

To understand the role of the neutral graduated filter

Technical learning

• ND filters reduce light across the whole of the image: they serve to introduce motion blur beyond the camera's unfiltered range. This is a specialist effect that is often used to give water a mist like appearance (see own image below) or to convey motion in  trees. 

Waterfall at Virginia Water Lake
Overcast conditions, ISO 100, f 22, ND filter 4 stop

• Graduated ND filters reduce light progressively over the range of the image: they serve to change the contrast between parts of the scene. Specifically they are designed to address one of the key challenges of landscape photography. Rarely can any camera cope as well 'straight' photography (see what the eye sees) between the relative brightness of the sky and the land. Expose for the sky and the land is usually too dark. Expose for the land and the sky is washed out.

Exercise instructions

Set-up

• Pick 3 scenes (a) a completely overcast day with a featureless sky, (b) an overcast sky with visible tonal differences and (c) a sunrise or sunset (shooting directly into the sun)
• Use a tripod
• Compose so that the horizon line is between 1/3rd and 2/3rds from the bottom of the frame

Images for all 3 scenes

• Bracket 3 images without filter with a wide aperture
• Bracket 3 images with the ND filter (edge at the horizon line) with a wide aperture
• Bracket 3 images with the ND filter with a small aperture

For one of the scenes

• Use a moderate telephoto lens at a small aperture
• Shoot 1 image without the ND filter, another with 

Review

• Examine how the filter balances the contrast between sky and land 
• Identify the differences in transition at the horizon between small and wide aperture
• Consider the impact of changing from a wide angle to a telephoto lens

Images and review

 

Field on the road between Pitminster and Corfe, Somerset

Images without filter - Bracketed +1/-1 EV

EV = 0

EV = -1 stop

EV = +1 stop

Images with 2 stop ND grad filter

EV = 0

EV = -1

EV = +1



Using a Tripod (33)

Requirement

6 images (2 x 3 scenes)

Purpose

To show the role of the tripod in securing sharp images

Technical learning

• Landscale images usually need a wide depth of field. So, small apertures have an important and regular part to play in camera craft. Therefore, tripods are an essential tool.
• One beneficial side effect is that using a tripod prompts a more thoughtful approach than the temptation to 'snap' with a hand held camera. 

Exercise instructions

• Identify 3 scenes
• Shoot each: one without a tripod, the one with
• Examine the differences

Images and review

Salisbury Plain

Abstract rhythm and textures of ploughed winter fields

ISO 100, f 22, 

Handheld on the same settings

Telephoto views - variety of images (32)

Requirement

Several images

Purpose

To appreciate the variety of compositions which use of a telephoto lens makes possible

Technical learning

• Telephoto lenses narrow the angle of view, so offer more potential images from a single viewpoint than wide angle ones
• The larger the focal length of the lens, the more variety of compositions it offers
• Nevertheless, this still creates a challenge

Exercise instructions

• Select a commanding viewpoint
• See how many satisfactory images of distant views you can create from one location
• Use vertical as well as horizontal framing
• Include the horizon in some, exclude it from others

Images and review

Views from hill above Upavon. No successful vertical frames were possible. 

 

 

Telephoto views - compressing planes (31)

Requirement

3 images

Purpose

• To explore the difference in impact between using a telephoto and a wide angle lens 
• To identify the factors that are important in making a successful telephoto image

Technical learning

'Seeing' telephoto is fundamentally different to 'seeing' wide angle - the telephoto lens:

• compresses distant planes and detail, so perspective/ depth is weaker
• makes depth of field shallower, so increasing the probability of out of focus elements in image
• works through more atmosphere, so colours are more muted
• reduces the angle of view, so makes it easier to eliminate unwanted elements and use vertical framing successfully

Exercise instructions

• Make 3 bracketed images of 'compressed planes' in a distant landscape

Images and review

Parque Natural Montes de Malaga

Bracketed images taken with telephoto zoom at 170mm and f8, using Panasonic Lumix G3

Impact was:

• to shorten distance between the shoreline and mountains in the background
• to get rid of a flat expanse of sea in the foreground
• to tone down the natural colours of the landscape
• to produce an image that is relatively sharp from front to back

-0.67 EV

Standard exposure

+0.67 EV

Wide angle lens - near and far (30)

Requirement

At least 3 images

Purpose

To shoot an image with a sharp foreground and background

Technical learning
Wide angles most suited to the following compositions or compositional effects

Panoramic images

• Use wide angle lens when you want to emphasise breadth rather than detail 
• Works especially well when used from a high viewpoint

Enhance perspective/ depth

• Use to make the most of the relationship between fore-, middle- and background. 'Near and far' was a technique used by Ansel Adams (see 3 examples below)
• Works well to create the impression of being in the scene rather than just observing it

Camera craft

• Pick a foreground with clear and interesting detail
• Position the camera low
• Be aware that small adjustments to the angle of view
• Use a small aperture to gain maximum sharpness 
• Be alert to the effect of wind in creating motion blur since shutter speed will be relatively slow at a small aperture (can adjust by dialling up ISO)
• Decide whether to use (the more natural) horizontal frame or (the potentially more dramatic) vertical composition (if camera is angled downwards)

Exercise instructions

• Find a scene with an interesting foreground and a distant view visible from a low camera angle (will require experimentation)
• Use your widest angle lens and a tripod
• Consider using a ND grad filter to balance the exposure of land and sky
• Compose the image so that near and far relate to each in sn interesting way

Images and review

 

Experiment with focus stacking. Set up tripod. Shot first image with focus sharp on foreground, second on middle ground and third on background. Then blended the 3 images into a single photograph using masks in Photoshop.




Near Mere, Wiltshire (lay-by off A303)

Re-photographing a well-known image (29)

Requirement
2 images

Purpose
To use the images of photographers who you admire to improve your own work

Technical learning

• To develop as a photographer get into the habit of analysing outstanding images -  viewpoint, lens choice, light conditions and other aspects of composition
• Visit the location, if possible, with a copy of the image to verify how the photographer made his or her choices in composition 

Exercise instructions

• Pick an existing published image that you would like to study
• Confirm what attracted you to it
• Work out lens length, light conditions, time of day and other ingredients of composition
• Visit the site
• Try to re-produce the version of your chosen image as faithfully as possible
• Then take a different view of the scene, however seems appropriate 
• What did you learn?

Images and review

I shot these images 6 months before writing up this blog post from my notes. 

Bluebells, Micheldever Woods

The published image

'As the sun rose, it was creating long
shadows with all of the trunks of the beech trees, but it was when
it hit the leaves of the branch that the scene came to life'
Simon Byrne,
published as an entry into the Landscape
Photographer of The Year Collection 5 (2011)

My version

1 hour or so after sunrise on 13 May (2012) 

after a 50 minute drive along M3 (which lies not far behind these trees). 

Similarities: 

• Location
• Subject matter
• Sunrise
• Bluebells in bloom (a 2 week wonder in May) 
• Long shadows of the birch trees
• Frame: 16 x 9

Differences: 

• Angle of sun (time of day): the sun in mine has a higher elevation so the light is more intense and has a different colour temperature than Simon Byrne's original. See the impact on the colour of the bluebell carpet on the forest floor: blue vs mauve. Also, in my image, the light has more of a presence, even if out of shot.
• Composition: mine lacks the prominent backlit branch and leaves in the centre of the image
• Viewpoint: mine has a standing height viewpoint, his knee high; the sun in mine is at a 30 degree angle to the left of the camera, whereas in his it is at a 30 to 45 degree angle to the right (lack of attention to detail on my part)