What makes a good photograph?
This largely depends on the PURPOSE of the photograph:
the photograph MUST attract the target audience's attention and HOLD it long enough to give the viewer the desired message such as the illusion that buying a product will give the purchaser the portrayed experience.
paparazzi / news / event photography:
here the content is king - how the picture is taken, the picture quality, the aesthetic aspects, all tend to be a distant secondary factor.
documentary and scientific photography:
again content is king - but now, picture quality with accurate rendition of the subject through appropriate focusing, lighting and exposure become important.
a subset of this is passport photos - see www.usvisanews.com/uscisphoto/guide.pdf on guidelines.
the family snaps:
again, the content is king, especially if it is spontaneous, although generally, the photo is usually needed to be flattering and show sufficient detail.
here, a portrayal of a person's features, ideally, both physical and personality/interests, are key, again usually the person prefers to be portrayed in a flattering view, making posture, lighting, choice of props, etc important.
generally, this falls into a few groups:
aesthetics is king, particularly with either colour, texture, form or abstraction, or, a combination of these being the important factor.
eg sunrise/sunset photos - see http://www.ronbigelow.com/articles/sunrise-sunset/sunrise-sunset.htm
eg. waterfalls - see http://www.ronbigelow.com/articles/waterfalls-1/waterfalls-1.htm
the key here is to portray the desired mood or emotion through appropriate use of medium, lighting, contrast, colour, subject, environment and expression.
the provocative photo:
the key here is to send a clear message to the viewer, to open their eyes to the desired viewpoint whether it be political, cultural, or otherwise
to be successful, it must attract a viewer's attention and usually needs to create some anxiety in the viewer, perhaps by juxtaposition of contradictory elements, or in your face portrayal of subjects that most viewer's would usually prefer to avoid.
the key factors in a photograph that allows one to make reasonable size enlargements with good detail are:
for a good tutorial on basics of photography, see http://www.xs4all.nl/~wiskerke/artikelen/basic1.htm
spending time to think about how you want an image to look which then will determine your choice of camera, lens, medium, composition, lighting, filters, shutter speed, aperture, ISO, etc.
often we find a scene that would be great but at a different time of day such as sunrise or sunset, and in this situation, you need to understand where the sun will be at those times of day and how it will light the scene - here a compass will help you as well as an understanding of astronomy as the sun will rise and set from a slightly different position each day.
if you want to make a 20"x30" enlargement with superb detail, you are not going to use a point and shoot digital, and you probably won't be able to use a 8-10 megapixel digital (although you can get away with these) or a 35mm film camera but you could choose a medium format film camera or a high end 17-22 megapixel digital, or if you are really a photo-"petrol-head" you might use large format film for the highest enlargement quality.
if all you want to do is make 8"x12" prints then an 6-8 megapixel digital or a 35mm film camera will be fine.
if you want to shoot high dynamic range scenes where you want detail in the shadows as well as the highlights, you would choose B&W film for its extended abilities to capture dynamic range or a digital camera with large photosites or bracket exposures and combine them, or use gradient filters.
if you want narrow DOF to blur out the background, consider a medium format camera or at least use a wide aperture lens or a tilt-shift lens
if you want a large DOF to keep everything sharp, consider a smaller format camera or at least a small aperture, but not too small that diffraction effects will lose sharpness, or consider a tilt-shift lens to change the focal plane.
control of subject movement:
at times, for dynamic effect, we may want subject motion to be visible, such as with panning an action scene, using a long exposure to show a flowing stream, or just to blur out distracting elements of a scene such as crowds.
it is much easier to blur a photo in PS than it is to increase its sharpness and detail - aim for as sharp as possible in the key subject region.
thus for most images, we want the subject to appear as sharp as possible, and this not only requires accurate focus but control of subject and camera movement:
using an adequately short exposure duration to "stop" any camera movement, or,
use a sturdy tripod, or,
some new digital cameras have "image stabilising" devices, or,
brace your camera to minimise camera movement,
use electronic flash with short flash duration
NB. for high magnification work such as macro or telephoto, or large mirrors, you may need to lock the mirror up to minimise camera vibrations.
using an adequately short exposure duration to "stop" any subject movement, or,
use electronic flash with short flash duration, or,
pan the camera with the direction of subject movement
using a flash to "stop" the action and avoid blurring due to movement :
ensure ambient lighting does not significantly contribute by ensuring your exposure is at least 3 stops under-exposed for ambient light levels - adjust this by changing shutter speed up to the shortest for flash sync for your camera (usually 1/180th sec for digital SLRs)
check the flash duration:
full output from many flash units results in flash duration of about 1/150th to 1/200th sec - probably not short enough to stop action
the Metz 50MZ-5 flash durations are:
1/200th at full GN50m; 1/500th at half; 1/1000th at 1/4; 1/2000th at 1/8th; down to 1/20,000th sec at 1/256 at GN 3m
thus, you may need to increase ISO, shorten flash-subject distance &/or open the aperture to achieve really short exposures
let's imagine we wish to use f/5.6 at 400ISO at 3m from subject with the Metz 50MZ-5 using a 50mm lens setting, the effective GN at 400ISO is 100m on full, but GN needed at 400ISO is 5.6x3m = 16.8m, and thus the flash would need to fire at 16.8/100 = 0.168 = 1/6th power which would give a flash duration of 1/1500th sec.
moral is: buy the most powerful flash you can so you can get to really short flash exposures.
your new camera has wizbang 10 million point 3D auto-exposure, so I can just put it in "Auto Program Exposure" mode and I will always get well exposed pics, right? WRONG!
not only is using brainless auto-exposure like saying you piloted a Boeing 737 and all you did was press the autopilot button, but it often doesn't give you the best exposure settings you need.
for a start, the camera is not going to know just how you want a subject rendered, you may want skin tones under-exposed for mood, or a little over-exposed for a high-key effect, furthermore, as the camera uses a "reflection" type of light meter it can be fooled such as:
a light background or a bright light will tend to result in an under-exposed subject & vice versa
personally, I almost NEVER use "Auto Program Exposure" mode as for a start, the exposure may not be what I want, but even worse, I don't have control over deciding on depth of field, subject motion and image noise, all of which are critical elements in the final outcome.
sure you can "bracket" your exposures by taking 3 photos all with different exposures but this will take up space on your memory card, potentially use up more time taking/saving the images that you might miss the best shot, and worse, end up with the best expression on the wrong exposure.
sure you can check the histogram on your digital, but this applies to your whole image, and if your subject is a small component then you may not be getting the information you need as it is flooded by the remainder of the image.
do yourself a favour and start to think about what you are trying to achieve and consider buying yourself an incident light meter to better understand light (preferably one that can measure flash light as well).
if your camera has a spot-meter then try using this.
try to shoot in RAW mode to give yourself the best options of adjusting exposure after the image is taken.
for the advanced photographers, other technical issues are:
lighting control - see lighting basics
grain/noise control - depends on film used, developer used, push-pull developing or digital ISO noise
sensor dust control - dust on the sensor will degrade every photo
most great photos convey an emotion to the viewer
if a scene creates an emotion in you, you have a good starting chance to capture that emotion in your image as hopefully this will spark your creativity, and then its up to your technical and creative aptitude to make the image work.
it is much harder to create something from a circumstance that doesn't do much for you, not impossible, but much harder, and often you need to be in a conducive frame of mind for this to occur.
The idea is to keep the viewer's eye involved with a composition by providing an interesting design. That can be done any number of ways, perhaps by offering the eye a circular route, a long graceful curve, or perhaps a back and forth attraction of two or more well balanced elements.
to attract an eye, composition should have:
an entry point such as the bottom left of an S-curve
an exit point
according to Gestalt theory, a cropped image which does not show the whole object but by cropping the resulting multiple entry and exit points to the subject from the edge of the image make the image much more dynamic and interactive with the viewer.
elements that attract the eye - the subject
a well developed centre of interest contains:
the strongest colors and if possible, complementary colours
a strong shift in contrast (light-dark), and keep contrast subdued elsewhere
should take up a reasonable proportion of the image
consider a "rest area" near the subject to make it less busy
balance between the elements
in general, the simpler the composition, the more pleasing to the eye
remove everything from the scene that does not contribute to the emotion you want to portray
remove unnecessary background and other features by choosing a mix of lens focal length and thus perspective, position of camera, shallow depth of field, shadows.
keep the corners subdued with little texture and values darker - perhaps even try adding a bit of vignetting but don't overdo it.
look for lines in your image and then work out how best to place them
implied lines and geometric forms can hold the picture together
horizontal lines denotes repose, calm, tranquillity
diagonal lines are dynamic, suggesting force, energy and motion, especially if flowing from left to right
curves such as the graceful female form are generally very pleasing to the eye, and denote beauty, charm
S-curves such as rivers, snakes, etc thus place them for maximum effect so they lead the eye to the subject.
a successful leading line will take the viewer to the subject and usually start in the lower left but not in the corner exactly
this uses the Gestalt theory of continuation by having a leading line in your image to keep the viewer within the image for as long as possible - see http://www.acdsystems.com/community/articles/phototips/article?id=2005-08-21
avoid leaning your lines outwards, leaning inwards is better
avoid straight lines unless they are short
avoid subject straight on, try for some diagonal lines
see also http://www.ronbigelow.com/articles/adv_comp/adv_comp.htm
look for balance of your subjects by creating geometric shapes or patterns that link them such as triangles
good balance of shapes, areas of light and dark are important for a pleasing, natural effect
often great images have elements that repeat throughout the image such as a series of triangular shapes or compositions. However, sometimes it is better to vary forms, so if there are round trees, avoid round clouds.
adding a secondary centre of interest for balance can work well and help keep the viewer's eyes alternating between the two, but it is important to ensure it does not compete with the primary subject
group you subjects of importance together and avoid scattering them around which would make them compete for attention.
avoid grouping elements in even numbers, if there is a pair, then use different sizes or positions for each.
equal or classical balance makes for dignity and repose but can be static and unimaginative
informal balance such as offsetting a large subject by a smaller secondary subject tends to be more dynamic and eye-catching
purposely making an image unbalanced can create tension and other emotions such as isolation, loneliness.
use of complementary colours such as red-green, orange-blue.
the rule of thirds helps create balance:
in general, subjects or horizons do not look good in the centre, but are better when a third from the edge of the frame.
avoid breaking your image into equal parts
balance of positive and negative space
balance of subject and background (see Gestalt theory figure ground)
choosing a tight perspective with subject occupying most of the image creates intimacy
choosing a wide perspective with background dominating creates isolation and loneliness moods.
create an illusion of depth:
place objects so they overlap but do not cause distracting mergers
atmospheric perspective - colors get cooler and lighter as they recede; fog is great for this.
create at least 3 planes - foreground, midground and background
consider using foreground elements to frame and focus attention on the subject
select your framing so that your subject faces into the image, not out of it.
avoid diagonal lines or S-curves originating exactly at a corner of the frame unless it is an abstract
make sure lines that should be horizontal are horizontal.
border mergers - cutting subjects at the edge of the image such as the top of their head or their feet.
near mergers - secondary subjects placed too close to the primary subject can distract and cause imbalance
background mergers - always avoid background shapes merging with the subject such as trees growing out of the subject's head.
Black & White Photography:
a B&W photo is not just a colour photo without the colour.
B&W photography allows one to concentrate on texture and form whilst ignoring the colour components which may otherwise detract.
thus a good B&W photograph is often one which has good contrast, whilst highlighting the subject's texture and form through appropriate camera angle, perspective, contrast control and lighting.
B&W in itself can evoke certain moods such as eloquence, romanticism or harsh realism.
B&W often allows patterns to become more evident, and situations that may appear a bit flat & boring in colour such as an overcast day, can be made to look great in B&W by forcing the viewer to concentrate on the patterns, texture & form.
B&W often makes skin tones more flattering by minimising the impact of blemishes, uneven colouring
by using coloured filters, one can render an object either lighter or darker and thereby alter the contrast of the photo, fortunately, in digital photography, this can be manipulated by adjusting the relative contribution of each of the colour channels instead of being forced to work with the one chosen by the optical filter you have chosen.
colour can be used to convey emotion and mood:
yellow - Autumn, happiness
red - warmth, danger, heat
blue - restfulness, passivity, cold
orange - Autumn
green - freshness
violet - nobility, elegance, warmth
using complementary colours together which increases their apparent intensity via simultaneous contrast:
Complementary colours are any two colours which lie opposite each other on the colour wheel.
complimentary colours may need to be used in appropriate ratios for balance
orange & blue
red & green
yellow & violet
using harmonizing colours:
these colours are found by using the points of an isosceles triangle on a colour wheel - if mixed together, they form grey.
red & orange harmonize with blue-green