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Composition
- When looking at a picture, you sometimes have the feeling that it is a "good" picture -
but you aren't able to tell why. You may of course like or dislike it for a lot of
subjective reasons - but there always are objective criteria explaining the impact of a
successful image.
What are these criteria?
- Technique - Content - Composition
Technique??
- It's all about knowing your camera, focusing, light...
Content??
- Your picture is likely to have a special meaning for you because you know why it was taken.
Anybody else however will be unaware of this background, and will find your masterpiece completely
uninteresting if there isn't any content to get him hooked. The picture may be technically
perfect...but that's all.
Composition??
- Composition refers to a set of guidelines intended to lead your eye towards the main subject
of the picture, and to keep it there...
What are these guidelines??
- In our Western culture, the eye analyses an image from left to right, and from top to bottom.
Living subjects (humans, animals) attract more attention than static components, such as
trees, mountains, stones, etc..
A picture including a figure will therefore have a stronger visual impact... which doesn't mean that you have to systematically include one in every picture you take..:o)
The centre of the image never is a strong point!!! Avoid putting the main subject in that area... Want to know where the strong points are? Here's the "trick" : divide the height and width equally into three sections -- the 4 "strong points" will be located at the intersections of the horizontal and vertical "thirds" lines...
The various sections delimited by these lines can in turn be subdivided in the same way, which will give "secundary strong points"...
What about the horizon line??
- It happens often that pictures that could have been really beautiful, are weakened because of
the horizon line being positioned exactly half way up the picture. Position it instead on one of the
horizontal "thirds" lines...
How to use lines??
-
In our Western culture, the reading direction goes from left to right, and from top to
bottom...
Following lines give rythm to a picture:
A diagonal running from the lower left to the upper right will be considered as most harmonious, and usually guarantee a successful composition.
A counter-diagonal tilting from the upper left to the lower right corner can very easily lead the eye out of the picture. This can be counteracted by including horizontal or vertical elements...
Use orthogonals to give an impression of depth
Curved lines do suggest softness... (feminine body curves, undulations of streaming water, corn fields stroken by a summer breeze...or a nice, quiet sunset)
Composition basically is a technique telling you how to arrange elements in an image.
You need to be aware of these elements, and to decide upon their relative importance, in
order to be able to create a feeling of order and harmony.
The eye can be led by perspective orthogonals, but also for instance by tonal ranges
accentuating the main subject within the image.
How do tonal ranges influence composition???
- For instance: Accentuation by putting a light subject on a dark background or by using colour contrasts.
Colour contrast are created by complementary colours - yellow and blue for instance.
How to use shapes??
- All forms haven't the same impact .... let's take advantage of this !!
- squares -> absence of tension - stability;
- horizontal rectangles -> tranquility - rest
- vertical rectangles -> strength
- upwards pointing triangles -> elevation
- downwards pointing triangles -> insecurity
- triangles with no side parallel to the borders of the image -> homogeneity
Finally...
-
- don't crop too tightly, as this brings the subject too near to the borders...
- Go for simplicity...but not for destitution
- Choose the right moment to shoot (light is all important...)
--- Set free your creativity ! ---
Sharpness, or blur ?
-
That's an highly subjective matter ! ! Dependent amongst other things on the kind of film and paper, as well as on the lens quality and type. You can have a "high definition" film -- if your lens is of poor quality, your picture won't be any good...
Sharpness....influenced by film ?
-
Yes. Each film has a a specific resolving power, i.e. an ability to separate the finest details. This is related to its sensitiveness and the local contrast of the details to be recorded.
Films with a low sensitiveness have a quite tiny emulsion layer, and very small silver halide crystals. They are known as " slow films ". They can record the finest details.
On the other side, when large crystals dominate, the film is considered having a " fast emulsion ". This kind of emulsion gives a larger tonal scale.
Sharpness....influenced by lens ?
-
You bet!!! Its optical quality is of utmost importance. You can't get sharp images with poor lenses. The resolution of a lens can be determined by using test cards. The resolution of a lens is decreasing from its center to the edges.
Sharpness.... influenced by the processing ?
-
Again, yes.
The processing temperature and the type of the developer will have an impact. Processing films at excessive temperatures and using inadequate developers can significantly increase grain, for instance.
At the printing stage, the stability of the enlarger, the focusing, and the quality of the enlarger's lens will all influence the final print.
Finally, a picture printed on glossy paper will always look sharper than on a "pearl" or matt surface.
Sharpness....related to our vision ?
-
Of course.... visual acuity !
At a distance of 25 cm (10"), the eye sees a 0.25mm circle as a point. An image composed by points of that dimension will appear perfectly sharp.
What about blur ?
-
An image will appear more or less blurred, depending on :
- exposure speed : a photographer can choose a slow speed to get some " motion blur " : running water, cascades, waves, persons in motion, etc...
- camera shake (nobody is perfect..)
- focus (depth of field depending on aperture, focal length of lens, focusing point choosen by the photographer)
- weather conditions (haze, air pollution)
- the use of special effect filters, decided by the photographer.
Sharp, or blurred ?
-
Again, this is highly subjective, and relies completely on the photographer's feeling.
Now, if ALL your pictures are blurred, you might consider changing your lens.... :o))
Some set absolute sharpness as a priority, other prefer some blurring effects. This might also depend on the subject : a wide-angle landscape usually is expected to be as sharp as possible.
--- Set free your creativity ! ---
Perspective
How to keep verticals?
-
The only requisite is to keep the camera's back parallel to the verticals of the subject. It's the camera's back which
determines perspective. All lines parallel to the film plane (and therefore to the camera back) will appear
perfectly parallel on the picture.
What's called "vanishing point" ?
-
When the film plane is not kept parallel to the subject's verticals, the latter will converge towards a unique point on
(or outside) the image. This point is called the vanishing point.
Is the focal length of any importance? ?
-
YES.
The shorter the focal length, the stronger the distortion.
How to keep controll?
-
For complete controll, you need a "View Camera"
View Camera ????
-
These professional cameras allow for front and rear movements. While all movements can be used
for Depth Of Field controll, it has to be kept in mind that for verticals correction, the rear
movements are restricted by the necessity to keep the film plane parallel to the verticals of
the subject.
Front movements ?
-
The front shifts and swings put the lens significantly off-axis, which requires that the lens has a coverage that is
substantially larger than the film format used.
But... what about 35mm cameras?
-
Either you put the camera on a tripod and check its position with a spirit level, making sure that
the back remains strictly parallel...
Or you take a PC lens (Perspective Controll) that allows some limited shifts....
Or you just pay particularly attention to what you see in your viewfinder, and aim your camera in such a way that the verticals remain as straight as possible (in which case the back of your camera will be practically parallel to those lines). You probably will have to back off from your subject.
Keeping things realistic.. ?
-
If you want to obtain an exact reproduction of your subject..
you better use a "standard" lens (that is, about 50 mm for 35mm cameras).
Remember: the shorter your lens, the more distorted your perspective will be.
--- Set free your creativity ! ---
Black & White Processing
Is correct film processing important ?
-
Sure it is ! It's essential. Changes in temperature, agitation or processing time will lead
to quite different results, even if you stick with the same film. You might be well inspired,
at least at the beginning, to follow the manufacturer's recommendations.
Why is the development time so important ?
-
Developing your film for too long will result in exaggerated contrast and coarser grain..
Insufficient developing gives "thin" and "flat" negatives (too clear and lacking contrast)..
On the other side, overexposure could be compensated by underdevelopment, and a film that was accidentally underexposed could be "saved" with a stronger developer, and a 2-3 minutes increase of the processing.
Why do reels turn black after some time ?
-
Because this is a silver-based process. In order to clean them up,
put them in undiluted domestic bleach (we call this "eau de Javel" here). Fix,
and wash thoroughly. They'll be as new!
PS -- The reels have to be absolutely dry before reloading another film -- otherwise you'll be in trouble...
The negative is too clear (lacks density) ?
-
The developer was exhausted or too cold (15º). Too low a temperature inhibits the
action of some reagents, such as hydroquinone.
Other causes might be underexposure or underdevelopment.
--- Set free your creativity ! ---
Polarized light and polarising filter
Is light propagating straightaway ?
-
Globally yes, however natural light is made up of waves that fluctuate at all possible
angles, as long as it isn't reflected by a smooth, non-metallic surface.
What's light reflection ?
-
Light ray reflection is the turning back of the ray to the environment it comes from,
when it encounters the edge of a medium..
This edge might be a surface separating two transparent mediums (a stretch of water) or a solid surface such as a mirror.
What's polarization ?
-
When light is reflected by a non-metallic surface, it contains waves that only
fluctuate in one specific plane. It is considered to be "linearly polarized".
What about polarising filters ?
-
A polarizer is a material composed by a microscopic grating that allows only light
with a specific angle of vibration to pass through.
A light ray passing through a polarizer therefore only contains waves that fluctuate in one specific plane, determined by the polarising filter.
What's the use of a polarising filter ?
-
A polarized light ray (turned back from a non-metallic surface, such as a shop
window for instance) can be completely eliminated with such a filter, under specific
circumstances.
You have to be at an angle of about 33° relatively to the incident ray (which strikes the surface).
You can't eliminate your own reflection (sigh..)
Does the type of lens matter ?
-
Yes.
The best result will be obtained with a telelens. When using a wide angle lens, only part of the reflections will be eliminated (those in the middle of the photograph).
Are there other means to eliminate reflections ?
-
Yes.
You might use a wide angle lens with a rubber hood, and put the latter against the window, for instance. Needless to say that the choice of viewing angles will be rather limited.. :o))
What about blue sky ?
-
Sunlight by itself is not polarized, but skylight is.
The sky appears blue as the shorter blue wavelengths included in white light are scattered more strongly by the molecules in the atmosphere than the other colours. These wavelengths being polarized, a sky can be darkened, using a polarising filter.
How to get a maximum darkening effect ?
-
The effect will be maximal when the line joining the sun and the camera forms an
angle of 90° with the line between the camera and the pictured part of the sky.
Other uses of the polarising filter ?
-
a) Reduction of haze
b) Increase of colour saturation and contrast
--- Set free your creativity ! ---
"Effects" ? What effects?
-
This term is used when referring to some reactions of light on film, under
specific shooting or processing circumstances.
Schwarzschild Effect ?
-
This is related to very long or very short exposures.
People refer also to this as "Reprocity Failure Law". Theoretically the product resulting from a combination of time and light volume should always be the same: an exposure to 1 lux during 100 seconds should give the same result as to 100 lux for 1 second. A same illumination should give the same darkening on the negative. Well..not at all! !
The effective useable film sensitivity declines with longer (1,2,3...sec) as well as with very short exposures (1/1000,1/2000, ... of a second). This is not linear and certainly not identical with different types of film. With colour films, things become even more complicated: as the various colour-sensitive layers react differently, one runs into colour balance problems, and correct filtering becomes extremely difficult or even impossible.
The film manufacturers provide Technical Data Sheets detailing the correct filtering and exposure requirements for each type of film. Get them!
Refraction Effect ?
-
Light is globally propagating straightaway. When a light ray passes from one
transparent medium to a different one (e.g.from air to glass), it is bended or
"refracted" (Descartes' Law - 1635) at their interface.
Beyond a specific angle, the ray is not refracted any more, but reflected (bounced back). A light ray can hit an emulsion, and be refracted into the film base at such an angle that it is bounced from the back side. The result is that the same ray is hitting the light-sensitive emulsion again, at a slightly different place, causing a blur or "halation".
To prevent this, an anti-halation backing is put on the back side of the film base. Its aim is to absorb completely the light passing through the emulsion, and to avoid that it penetrates into it again.
The dyes used for this have to be easily removable by the developer. It usually is an acid dye (generally blue, green, brown or yellow for panchromatic films).
"Callier" Effect ?
-
The light-sensitive layer being a mixture of gelatin and suspended silver particles,
light rays will get easily through the clear parts of the negative, while in the dense
parts of the negative, they will be reflected backwards, absorbed or scattered.
Into what extent this produces a measurable effect on the amount of light reaching
the paper depends on the type of light source .
If you have a colour head (diffused light source) on your enlarger, you don't have to bother about this.
If your enlarger uses incandescent lamp bulbs and condensors (directed light source) you certainly will be facing this phenomenon, called the Callier Effect.
In the clear part of the negative, more light will reach the paper with a condenser head, as a diffuse light source is already very scattered. In the high density areas however, the directed light source produces the most scattering, hence producing the greatest attenuation of light.
Prints made with a condenser head enlarger will show more contrast. There will also be an increase in sharpness; however, this includes increased visibility of grain, scratches, other defects in the negative as well as dust on it.
These benefits/drawbacks are somewhat attenuated with the use of opal or frosted lamp bulbs.
Sabatier Effect or pseudo-solarisation ?
-
The Sabatier effects consists in a uniform fogging of the image during the development.
The result is increased density in zones where the silver particles weren't affected by the developer yet, and a reversal of some values. The image appears part positive, part negative with black highlights and perhaps a few thin white lines around the edges of some areas.
The most basic way to achieve this is to switch on briefly the white light part way through the development. Of course, being able to get consistent results (as opposed to pure luck) supposes a lot of trial-and-error, and ...a big trash can.
--- Set free your creativity ! ---
Claire L.
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