Project 35: using a polariser

I actually took the photographs for this assignment before I completed project 33 on using a tripod.  As I was out hill walking I fell into the trap of being lazy as I explain in the blog for Project 33.  It is all too easy to decide to leave it in the car when I am carrying a heavy rucksack anyway.  I feel even more humbled when I think of the heavy loads carried by Ansel Adams and Joe Cornish.  I must get into the habit of using my walking pole which has a tripod bush in the handle.  All I would need to carry then would be my lightweight tripod head.

For the first part of the project I took pictures when I was out walking with my brother in Derbyshire on Derwent Edge above Ladybower and Derwent Reservoirs.  It was during a cold spell and we had had snow but this morning dawned bright and bitterly cold.  Kinder Scout was on the horizon at right angles to the sun with a bank of cloud just above the horizon so perfect for using a polariser.

For the second part I was out walking in the Lincolnshire Wolds and came across a trout lake which fitted the bill perfectly even down to the rocks under the water.

I images are shown below:

85mm lens setting

As we climbed up onto Lost Lad I noticed that there was a lovely bank of cloud hanging above Kinder Scout on the horizon and at right angles to the sun.  For this picture the polariser was rotated so it had no effect.

The difference in this second image is amazing.  Here I rotated the polariser through 90 degrees to get the full effect.  The sky is darkened and the clouds stand out beautifully.

17mm lens setting

Using the same view I set the lens to its 17mm setting and rotated the polariser so it had no effect.

Here the polariser was rotated to give the full effect and this is very noticeable.  The clouds stand out and the sky is very much darkened to the right of the shot on the side furthest away from the sun.  At this wide angle setting the lens covers more of the sky, including areas closer to the sun where the light is not polarised.

Photographing water with a polariser.

In this shot of a local trout lake in the Lincolnshire Wolds I rotated the filter so it had no effect.

In this shot, where the filter has been rotated to maximum effect it can be seen that many of the surface reflections have been removed and the rocks and detail on the bottom of the lake can now be seen more clearly, particularly in the foreground.

What Have I Learned
A polarising filter can be used judiciously to darken a blue sky, bring out detail in the clouds and increase saturation in the image.  It can also reduce reflections on water.  It can, however, be overused, especially with a wide angle lens where the effect is uneven.  It works best with standard focal lengths to medium teleohoto.  The best effect is seen when facing at right angles to the sun and there is litte effect when in line with the sun.  To my knowledge it is one of the few, if not the only filter, whose effect cannot be duplicated in today's processing software packages.

Project 33: using a tripod

As a general rule I tend to make a great deal of use of my tripod.  Actually I use 2: a lightweight Manfrotto carbon one when I am carrying it far and a more robust carbon Feisol.  I have a couple of ball heads of different weights and a gimbal style head which I use with my 500 lens for bird photography.  There are times however when I choose (am too lazy) not to use a tripod and hand hold.  This is generally when I am out mountain walking, but then I tend to use a walking pole with a tripod bush, or when using a very fast shutter speed for bird flight shots.  I always use a tripod for macro work.  Recently I have thought tjhat some of my landscape images are not as sharp as I would like so I am not only making it a rule to use one, but I am I am using f16 to avoid the fall off in lens performance at smaller apertures and I am also using mirror lock up a cable release.

Below are the 3 pairs of images that I have taken for this project.

With tripod

No tripod

With Tripod

No tripod

With tripod

No tripod

The first two pairs if pictures were taken in Irby Dale on the edge of the Lincolnshire Wolds.  Both are wide angle shots and although there is less sharpness in the shots without a tripod when viewed large the difference is not too significant.  The final pair of images was taken at Worlaby Carrs, a site I visit to photograph the short-eared owls that congregate there during the winter.  Here I shot at 85mm and by using a short telephoto and 100 ISO  it can clearly be seen that the none tripod picture definitely lacks sharpness.

What have I learned.
Using a tripod helps to achieve crisp, sharp images.  It also allows the use of low ISOs and small apertures which mean greater depth of field and no noise.  Using a cable release and mirror lock up also helps to achieve sharp images as the vibration from 'mirror slap' is removed or reduced and there is no movement generated by physically depressing the shutter.

A Walk in the Lincolnshire Wolds

I recently went fora walk in the Lincolnshire Wolds with my wife.  It was a day of mixed cloud and sun and produced some wonderful clouds and lighting.  I have included a selection of the images I took below.

Binbrook

Looking back to Binbrook

An ash tree high on the Lincolnshire Wolds.  Will it survive.

Project 34: using a graduated filter

For this exercise I opted to take the required images and then employ the ND grad feature in Lightroom 4 as it is so good and doesn't give the  problems with colour casts that I experience with my cokin filters.  These tend to give a magenta cast, especially if I use more than 1 in combination.  Maybe one day I will push the boat out and invest in some Lee filters.  In retrospect, perhaps I should have completed the exercise using the physical features in order to see the subtle difference between  wide and narrow apertures.  In all cases I bracketed the exposures by 1 1/2 stops either way and when filtering used a 1 stop filter.

Completely overcast day with a featureless sky.

It is suprising how difficult it is to get these conditions when you need them.  I grabbed the opportunity and photographed from our loft window rather than going out and having the sky clear on me.

    F4 Images

• Images taken with the aperture set at f4 and at the meter reading

f4 unfiltered

f4 filtered

• Images under exposed by 1 1/2 stops

Underexposed by 1 1/2 stops and unfiltered

Underexposed by 1 1/2 stops and 1 stop ND Grad

• Overexposed images at f4

Overexposed by 1 1/2 stops and unfiltered

Overexposed by 1 1/2 stops and 1 stop ND grad applied

Although the sky appeared to be featureless it can be seen that there is some detail even without filtration although the use of the ND grad does both darken the sky and bring out the cloud detail.  Without any other post processing, perhaps the meter reading filtered image is the best but with a 2 stop ND grad the over exposed image would probably be the best.

       F22 Images

• Images taken at the meter reading

unfiltered

Filtered

• Images underexposed by 1 stop

unfiltered

filtered

• Images overexposed by 1 stop

unfiltered

filtered

The results here can be seen to be very similar to the images shot at f4.  Again the picture that was overexposed slightly seems to be the best and would have been even better with a 2 or 3 stop ND grad.  The foreground certainly has a better exposure.

Clouds which show some difference in tones.

I took these shots whilst out walking in the Lincolnshire Wolds on a day of mixed cloud and sun.  I waited until the sun was obscured and then took these shots.  The clouds showed a great deal of structure.

F4 Images

• Meter reading

unfiltered

filtered

• underexposed

unfiltered

filtered

• overexposed

unfiltered

filtered

Of the above images, I prefer the filtered meter reading one, although I think that the one that is slightly overexposed would be the best with heavier filtration.

F22 Images

• meter reading

unfiltered

filtered

• underexposed

unfiltered

filtered

• overexposed

unfiltered

filtered

Again I noticed the same difference between images.  This time I think the meter reading and filtered shot is the preferred one.  I like the sky on the underexposed image best but here the foreground is too dark.  One major difference was in the sharpness of the images.  When the trees on the skyline are observed at 100% the f22 images are distinctly sharper.

The best image from each situation with post processing.

In both cases I worked on the meter reading image.

Here I increased the filtration to 3 stops and slightly increased the clarity, vibrance and saturation of the image.  I set the white balance to cloudy.

Again the filtration was increased to three stops and the clarity, vibrance and saturation increased slightly.

A few days later we experienced a truly featureless sky and so I repeated this part of the exercise but have only displayed here the meter reading images at f22.  It can be seen that when a sky is truly without detail no amount of filtration can help and it only succeeds in darkening the sky.

unfiltered

filtered

Sunset Images

F4

• meter reading

unfiltered

filtered

• underexposed

unfiltered

filtered

• overexposed

unfiltered

filtered

Again it can be seen that the ND grad filter darkens and increases the detail in the sky.  The underexposed and filtered image gave the most dramatic sky but the foreground is too dark unless the aim is to produce a silhouette but as the metering was taken from the houses in order to show some detail in the foreground.  I have shown a further image below where I have started with the f22 image taken at the meter reading on the houses.  I used the ND grad on the sky but the houses were still too dark so I used a second ND grad in Lightroom to increase the exposure on the houses whilst leaving the sky unaffected.  Just increasing the exposure also reduces the drama in the sky.  I also slightly increased the saturation, vibrance, clarity and also colour temperature.

Telephoto Pictures.

Whist out in the Wolds I zoomed in to 85mm at f22 and reproduce here a filtered and unfiltered image.

unfiltered

filtered

Although the detail has been increased in the sky, the effect is less marked.  Of course, the 1 stop ND grad could have been replaced by a 2 or even 3 stop one to increase the effect.

What Have I Learned.
Often, especially in cloudy conditions the sky can be rendered featureless in a landscape image.  In this situation an ND Grad can be used to both darken and increase detail in the sky.  The effect has to be tempered, however, otherwise the effect can be too dramatic.  If the sky is too featureless filtration doesn't help.  ND Grads can be used in sunset images if detail is still required in the foreground rather than a silhouette effect.  If a silhouette is preferred it is satisfactory to meter off the sky.  A variety of exposures can be taken in order to select the preferred image.