First of all, you need to understand WHY you are taking the photo.
THEN decide WHAT style/theme/context you need to create to try to get the best outcome for that purpose.
Evaluate the subject's features to determine what will be the best poses, lighting, etc to achieve your outcome. What happens to their features when they change expressions such as smile - assess this from both front on and from classical 2/3rd face viewpoints. Are there any negative or distracting features at certain expressions or angles?
You then need to use your creativity to imagine a fabricated scene that will suit the style including approximate positioning of the model, what props will be used if any, the approximate camera position required and what sort of background you need.
The model's makeup, hair styling & clothing need to be selected and applied.
In general, the best clothing colors are medium shades of blue, green, burgundy, and rust, while most will do best with legs and arms clothed to avoid taking attention away from the face.
Set up the background with the backdrop you feel will most suit the theme
Set up the approximate positioning of model & props
generally, avoid bare arm pits - use props such as hair, clothing, material, flowers, etc to hide them.
Adjust the position of the camera to ensure you will get the appropriate viewpoint, ensuring that the backdrop will completely cover the frame.
Decide on a exposure setting to be used and remember to use a good lens hood as lens flare will adversely impact most photos, especially low key styles.
Set up the lighting for the backdrop.
Set up a fill light for the subject
this boosts detail in shadow areas & reduces excessive contrast - once positioned, can just adjust its power or distance to adjust contrast.
usually near the camera position - and usually a large light source such as umbrella or soft box, but may be a reflector or if desperate, the on-camera flash. Usually this will create a catch-light in the eyes so be aware of its position. If it is too far from the subject, the output needed may effect the lighting of the backdrop so you may need to bring it closer to the subject and lower its output accordingly. The fill light will usually be adjusted to - 1 stop to -2 stops exposure compared to main light.
Set the model's pose so that the following lights can be adjusted precisely for best effect
Set up the main light:
this sets the light level & mood for the shot - although to simplify things I suggest adjusting it to the pre-determined exposure level
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if the model is wearing glasses and you can't use glasses without lenses then:
shoot more Loop style with large soft light source above and to the side to reduce flare and also shadows from the frames, then fill the other side using a reflector
AVOID front lighting unless the light source is high enough not to be in reflected in the glasses
if the model has appropriate makeup then a small light source such as a snooted monobloc can be used to provide good contrast and special effects, otherwise you may have to resort to a broad light source such as a soft box to minimise skin blemishes, oily skin, etc.
decide on the position depending on effect needed and facial features of the model:
butterfly “glamour” lighting with light direct on to face - good for skin blemishes, minimising a big nose BUT catchlight will be in 12 o'clock position, and ear is lit up
Hollywood-style loop lighting set 45deg up and to the side of the nose to create a nasal shadow going towards the lip & highlighting the cheek.
often used in short-lit portraits with shadow side of face towards the camera
the opposite edge of the far side cheek will be in shadow and this may require a fill light such as a reflector
often used with harsh lighting to great effect but can be used with soft lighting
tends to lengthen faces a little and give the appearance of slightly higher cheekbones
good for oval shaped faces
can be short-lit to make the face appear thinner
this is perhaps the most flattering of all lighting for all subjects
use in broad-lit portraits with lit side of face towards camera to subdue skin blemishes & help widen narrow faces - catchlight will be in 2 o'clock position
Rembrandt lighting with light at 45deg to face, higher than loop lighting and usually with no fill light
the nose shadow angles down towards the end of the lip but not crossing it
the aim is to give a small triangle of light on the near cheek below the eye, but to do this means the catchlight is lost as the main light must be placed too high. To address this, a second main light is needed in the modified butterfly position at less than half intensity of the main light so it gives the desired catchlight. (see
http://jzportraits.home.att.net/chapter-13.html)
very effective in showing character
good also when wearing a hat or cap
split lighting
key light is 90deg to the face so only half the face is lit by that light
great for adding drama, often used in fashion, commercial work and makes a broad face look slimmer
it is not great for subjects where the light hits the shadow side cheek more than it does the shadow side eye
also not great for subjects with big noses
you may need to hide the subject's lit ear and show as little of the white of the eye as possible to avoid a glazed look
low angle lighting for an eerie or mysterious effect but has limited application - catchlight will be in 6 o'clock position
Set up hair light or kicker lights:
brings out detail in the hair & adds a glamour effect, while any side lights give definition or contour to the subject, creating separation from the background and adding contrast.
these tend to be aimed at or behind the hair (for a more subtle grazing effect where you need more control over lighting intensity) from either above and behind the subject or below and behind the subject.
usually need to ensure that the light will not pass through gaps in hair.
the intensity of the hair light is usually set to approx. 1/10th - 1/3rd stop more than the main light but this depends of colour of the hair with brunettes needing more than blondes. In general, subtle hair light is better than blasting it.
Consider a reflector below the chin to add light to the eyes, but beware:
that you don't light the neck too much and lose the chin outline
the resulting light hitting the nose from below may cause unwanted shadowing in the inner corners of the eyes
that using a gold reflector may create a yellow catchlight and make the model look sickly.
Re-check that there is at least one catchlight in each eye - but if there is more than one and it is complicating the image, re-adjust the lights to simplify it if possible.
Ensure the lights are not directly hitting the camera lens - use cardboard, etc to block them if possible
Final position of subject's face, ensuring lighting is hitting it correctly
Choose the best camera angle to enhance the subject's features:
the features closest to the camera are the ones which will appear larger and be emphasised - take care in what you emphasise!
broad lighting means having the camera on the same side of the face as the key light
short lighting means having the camera on the opposite side of the face as the key light and thus most of the face is in shadow
flat lighting means having both the camera and key light front on to the subject's face and at same height
this will make cheekbones, nose and jaw appear wider so is not great for those with broad faces
the lack of shadow and texture effects makes it great for those with skin texture issues, wrinkles and under eye bags
this lighting can be made more flattering by creating shadows to each side of the face by using black flags on each side
a variation of this is butterfly lighting (see above) which minimises the nose, creates more dramatic lighting of the cheek bones and brow bones while creating a more defined jaw line and is thus great for those with a double chin or lumpy nose
in general, its best to use a normal camera position with an appropriate focal length lens
film plane should generally be parallel to the facial plane for head/shoulders and to the overall body plane in 3/4 length poses which then requires a further tilt of the face to match the camera's plane.
for full length standing subject's:
the film plane must still be kept parallel to the subject which usually means the camera is between chest and waist level, again the head may need to be tilted to match the camera's plane, although as the face is now much smaller component of the image, this is not so critical.
for 3/4 length shots:
for head-and-shoulders close-up shots
use a telephoto lens, which is about 105-135mm for full frame 35mm
camera usually at eye level
slightly higher position (8“ above eye level) enhances a short, turned up nose and minimises a double chin which means it tends to be more flattering on most women
slightly lower position enhances the appearance of a long nose and tends to intensify the image
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NB. in group portraits, aim to keep all faces in the same plane
pose the face for a defined jaw line
Focus the camera - usually need to focus on the closest eye for best impact.
Now that all is ready you need to take your head away from the camera a little and get the model to give you the facial expression you need.
If the model is to be looking “at the camera”, get her to look into YOUR eyes with your eyes just to the side of the camera - eyes look best when they are looking at another person rather than a camera.
if you want the model to look elsewhere, move to the position you want them to look at to make it easier for them to understand what you are asking, or hold your fingers up to the point you want them to look at
pose the eyes - the eyes usually look best when:
they are facing in the same direction as the nose
there is some space between them and the hair line or edge of face (check this when shooting with subject turned away from camera)
if one eye is bigger than the other, place the bigger eye on the far side of the face to balance them out
if subject is to gaze upwards, ensure they relax their forehead to avoid frown lines
direct the subject maintaining your eye contact so they don't lose position, but use directions from the subject's perspective (ie. more YOUR right hand) supported by your hand gestures to explain which way you want them to tilt
obtain the expression you want from the subject by asking them to think of the emotion or a scenario that will give that expression, try getting them to interact with an imaginary person for example
Don't feel stressed out when you can't get the shot that you had envisioned in your head all day, go with the flow. If you are stressed out, your subject might start to think it is their fault. Some of the best portraits are complete accidents. Consider having the model pose in a very relaxed manner even if the position of arms, legs, etc are not aesthetic, if the model is relaxed you can go for a tight head shot which may just give you a great shot that forced poses don't give you, and then you can move on with more confidence. One of the keys to successful portraits is the photographer conveying confidence - after all, the model tends to mirror the photographer. If you are getting stiff expressions, try the technique of getting the model to look away then when you are ready, to turn head and look back towards the camera with the attempted expression.