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5. Natural Light – Project 44, Low Sun

(viewed 472 times)
“Low sun” is, roughly, within about two hours of sunset and of sunrise.

The photos here are all taken when the sun was low in the sky.

• Frontal lighting, sun behind the camera, shining full on the subject.

• Side lighting, sun to one side or the other, subject in half-shadow.

• Back lighting; shooting towards the sun, subject often in silhouette (bracketing the exposure often a good idea).

• Edge lighting; shooting towards the sun with the sun outside the frame, lighting the rim of the subject.

This project shows that at this time of day, when the sun is low in the sky, a huge variety of lighting is available, just by changing one’s viewpoint.
6th Oct 2009, 05:30   comments (0)

5. Natural Light – Project 43, Through the day

For this project I needed an isolated subject (the Buitenmolen) quite near to home because I’d need to go there, to the same spot, on the hour, every hour, from dawn till dusk and photograph it.

After having collected the images I laid them out in front of me (on the computer screen) and took a good look. The colour differences are much greater in the images than appeared at the time. This is due, as previously noted, to the eye/brain compensating for these variations automatically and the camera not.

The First two, at 9 & 10am show a “warm” colour to the brickwork and a clear shortening of shadows.

Unfortunately the rest of the day’s pictures from that exact angle were all blown-out sky & a mill in shadow or silhouette so I changed my position to the other side and tried again there.

At 12pm the whole image is “neutrally” lit, the sun being at its highest point.

The last of the images, at 6pm, shows that warm light on the brickwork again before the sun dips behind the pub on the opposite side of the road.

I’ll add the “missing” images when the sun decides to shine again for me.
(edit; images added)

Most casual snapshots are taken in the middle of the day, somewhere between mid-morning and mid-afternoon. The casual amateur won’t be up before dawn, travel to the location and be ready to shoot as the sun comes up. Likewise at the end of the day – there are the practicalities of getting home in time for tea to consider. The serious photographer however will get out there when the light is “better”.

(I’ll set my alarm)
6th Oct 2009, 05:21   comments (1)

5. Natural Light – Project 42, Judging colour temperature

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This project required me to take three pictures of a face (for instance) in different light conditions.

The first image is in direct sunlight in the middle of the day.
The second is in full shadow at that same time of day.
The third is when the sun is very low on the horizon.

Studying the resulting images it is clear that there is a colour difference visible. Our eye/brain will compensate for this variation and, at the time, it will seem natural. The camera however does see these differences and reproduces them on paper. Sunset shades are much redder than at midday and there is a distinct blue tinge to shots taken in the shadows. A straw coloured filter, in various strengths, is available to “warm up” shadow light. On the Kelvin scale though Red-Orange is cooler than the bluer tones, We talk about Red-Orange being “warmer” than the “cool blues” but on the Kelvin scale this is the opposite (imagine an iron bar and how it heats up, first dull red, then orange, through yellow to blue(ish) and ultimately “white hot”).

Next we need to look at the three images and decide what, if any, correction they require. The midday sunlit one is already neutrally lit but the other two may need correcting. This can be done with the use of filters though often a sunset “orange” is left as-is because we find this pleasing to look at. The blue tint in shadow images can be corrected though.
Little can be done about the changing light throughout the day, we can however choose when we do the shoot.

Son #2, Mike was my (reluctant) model for this project and did the teenage disappearing thing when I needed him for the sunset shot. I’ll grab him next time he passes (and the sun shines).
6th Oct 2009, 05:16   comments (1)

5. Natural Light – Project 41, Your eye’s sensitivity to colour

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Light is electromagnetic radiation, as are radio waves and X-rays, though our eyes are only sensitive to a certain part of that spectrum.

Radiation is wavelength, from very long wavelengths (radio waves) through infra-red to deep red and the beginning of what for us is the visible spectrum. As the wavelengths get shorter we see red, orange, yellow, green, blue, violet, deepening to very dark purple where we “lose sight of it” as it shortens to become ultra-violet light.
Sunlight contains all the colours of the spectrum which, when mixed together like that, appear to us as “white light”.

Arranging the images gathered for P32 & P33 according to the spectrum (red on the left, through to violet on the right) I have “lowered” the darker-looking colours and “raised” the lighter tones. This has produced the “graph” illustrated in the picture.

Light becomes colour when part of the spectrum is missing. The “white light” in the middle of the day (containing all the colours) becomes yellower and then redder as the sun sets. This is because the lower angle of the sun makes the light pass through more of our atmosphere. Dust and particles in that atmosphere will scatter some of the light. This selective scattering will affect the shorter wavelengths more, the blues are proportionally more affected, leaving the reds and oranges.

23rd Sep 2009, 13:50   comments (0)

5. Natural Light – Project 40(b), Using a meter

Part 2

Five images here, all “bracketed” in the following manner;

+1 f/stop, +0.5 f/stop, Correctly Exposed, -0.5 f/stop, -1 f/stop

The “correct” exposure, in the middle in each case, is marked in red.

In the first series, the overview of my truck (I’m stuck at the side of the road, broke down, waiting for a part to be couriered-in), The middle image is, in my opinion, the best choice. This is probably due to there being no “extremes” in the frame which means that the “average” is in this case correct.

The next strip, the front of the vehicle, has a few bright areas where the sky is reflected, this makes me choose the -0.5 f/stop image over the middle shot, the blue is that much “richer”. The -1 f/stop one is a little too dark.

To throw the cat amongst the pigeons I shot a series straight into the sun. The camera’s meter has shut everything down to try and compensate for that huge amount of sunlight, making the subject almost completely black. The +1 f/stop image is here the better one, showing some detail in the subject but, of course, blowing out the sky completely.

Next I put a single wheel filling the frame. This subject has dark elements (the rubber) and lighter parts (the steel wheel) and, as I expected, the middle image is the better option. This is because the “average” is indeed average in this case.

The last image, the close-up of the headlight, is interesting in that I feel all five exposures are acceptable. The lighter of the bunch because it shows more detail in the darker areas through to the darkest of the group because the individual highlights are more prominent and there is detail visible within those highlights.
1st Sep 2009, 19:59   comments (3)

5. Natural Light – Project 40(a), Using a meter

CCD sensors are less efficient at recording than our eyes. A well exposed image will most resemble how our eyes saw the scene. The highest highlights and the darkest shadows should still contain visible detail.

Most scenes are neither all black or all white, a light meter will take an average reading of the scene it’s presented with. This works well most of the time. The camera attempts, as it were, to produce an “average” image, a grey canvas at 50% brightness or 128 on a scale of 0 – 255. The trick is to decide what you, as the photographer, want the image to look like rather than the camera’s software (or, in other words, some technician in a lab in Japan five years ago). Do you want to see a darker or a lighter image, are there important elements within the image that are darker or lighter than the whole?

These ten images are either deliberately darker or lighter than the meter would have me set the camera. The histogram for each image is (deliberately) bunched up at either the left (darker) side or the right (highlights).

The first three, in the flooded woods, have been under exposed so as to create an atmosphere, the dark & dangerous woods, and some dodgy-old photographer out there taking snaps. If left to the camera’s own calculations they would all have been flat and grey.

The Angel of the North was put into complete silhouette against the evening sky to allow the colours of that sky to show through and also emphasise the strong shape of the massive statue. The camera’s own metering would have blown out the sky and done its best to show some detail in the foreground and subject.

The view of Newcastle from the bridge was darkened so as to show the threatening skies, the texture in the clouds. Again, a “correct” exposure setting would have made for a less dynamic image.

The lighter images have all overridden the camera’s urge to produce grey averages. When you want lighter results ignore the camera’s protestations and flip to manual.
1st Sep 2009, 17:26   comments (3)

5. Natural light – Project 39, Using Faster film & higher sensitivity (I)

When the sun is bright enough in the sky it is “easy” to use a camera. There will be enough light to enable the use of a shutter speed fast enough to freeze any movement, either from the subject or in-camera and with an aperture small enough to give a reasonable depth of Field.

A shutter speed of 1/125th should suffice and an aperture of f/5,6 provides a moderate D of F. The readings off the graph in P38 suggest that this would be attainable (at ISO 100) throughout most of the day, only very early or later would we need to think about selecting a faster ISO.

With the camera set to manual, these five images were taken, hand-held, in failing light, at an ISO setting of 100. f/5,6 was the widest aperture possible for this lens, the 18-135mm and I stuck to it to allow for the fastest possible shutter speed in the light conditions.

The cut-out section shows the detail within each image. At ISO100 it is obvious there is a fair amount of camera-shake.

1. 1/20th sec
2. 1/30th sec
3. 1/30th sec
4. 1/30th sec
5. 1/20th sec
27th Aug 2009, 21:55   comments (2)

5. Natural light – Project 39, Using Faster film & higher sensitivity (II)

The next set of pictures, under the same circumstances, were shot at ISO400.

Here again I have focussed on a section of the image’s detail to illustrate the sharper lines.

1. 1/90th sec
2. 1/125th sec
3. 1/125th sec
4. 1/125th sec
5. 1/90th sec
27th Aug 2009, 21:54   comments (1)