Showing posts with label Speedlite. Show all posts
Showing posts with label Speedlite. Show all posts

Wednesday, 26 June 2013

Exercise: Contrast and shadow fill

In this exercise we are looking at ways of controlling contrast and filling shadow by means of reflective surfaces.  This is an effective alternative to using additional lights in order to achieve the same effect, particularly when working with natural light.  Here, however, I am using artificial lights throughout in order to demonstrate the different effects.

Once again, my patient mannequin is roped in to assist.  The lighting set up is simple as shown in the diagram below.  This diagram shows multiple reflectors, as they were used in different stages, as well as the two lighting sources, a bare flash (Speedlite) and a softbox.
The exercise is in several parts, with, first of all a reference shot using flash without modifier and no reflector and then a second shot using a diffuser (softbox).  During this exercise, the Speedlite was used at half power and the camera settings were:

  • bare flash - ISO 100, f/22, 1/125 sec; and 
  • softbox - ISO 100, f16, 1/125 sec

Bare flash                                               Softbox
These two reference shots clearly demonstrate the difference in contrast between them.  The light from the softbox is a much softer light and provides a smoother transition from light to shadow as well as achieving a more even tone.

The following sequence demonstrating shadow fill, making use of reflectors all use the softbox as the light source.  Apart from the silver foil sequence, I used a commercial, generic, 5-in-1 reflector obtained from Warehouse Express (wex) at a photo show.  As the silver foil behaves differently to the material, I used that in preference.
White 1 m                                              White 1/2 m
This first pair of the sequence also illustrates the effect of the inverse square law.  When the distance doubles,  the intensity of the light falling on the subject decreases by a factor of four.  A white reflector creates a soft light and this can be seen here.  Reducing the distance from the initial 1 metre to 1/2 metre increased visibly (4 times) the amount of light falling on the head, filling in the shadow very well.  The closer the light source is, the larger it becomes in relation to the subject and the softer that light becomes.  This can be seen here with the soft fill from the reflector.
Matt                                                                Shiny                                                         Crumpled
The results of using silver foil with the matt and shiny sides and then the crumpled shiny side did not entirely happen as I had expected.  I expected that with the crumpled shiny side there would be light loss due to being scattered, but this also would create a softer light compared to that hitting the foil in the first place.  This soft light, reducing contrast can be seen here.  It is the difference between the matt and shiny surfaces which I found interesting.  I expected the matt surface to produce a softer fill, but seemingly, it has also provided a higher intensity of fill compared to the shiny surface of the foil.  Expectedly, the shiny surface has a higher contrast when compared to matt, but in theory it should have the same quality as the original source. By that I mean, if a hard light strikes a smooth, mirror-like surface, then hard light would be reflected, whereas a light from a soft or diffused source would reflect soft light.  There is one further variable to be considered here.  As the light has travelled further from the diffused source than that which falls on the subject nearest the source, then the light will have decreased in intensity and will be less soft as the light source is further away.
Gold                                                     Black
I wanted also to show the effect of gold and back surfaces.  The warm light can be clearly seen creating a warmer fill in the shadow area.  The effect of the black surface, which is subtractive, increases contrast and adds depth to the shadows.


Arranging the shots in order of greatest shadow / contrast to least, I have created the above, with greatest top left, running along top row to bottom row least as bottom right.

The results are:

  • black;
  • white at 1 metre;
  • crumpled shiny foil;
  • shiny foil;
  • matt foil;
  • white at 1/2 metre.

Out of interest, I repeated the exercise using the bare flash.  The net effect is much the same, taking into account the harsher light and therefore higher contrast, particularly evident in the main sharply defined shadow line running across the head.

References

How to control & use photographic lighting - David Brooks

Portrait Photography, Secrets of Posing & Lighting - Mark Cleghorn


Sunday, 23 June 2013

Exercise: The lighting angle

The position of the light source in relation to the subject will create different effects, some of which will show the form, some the shape and some will enable the subject to be separated from the background.  The purpose of this exercise is to demonstrate this modelling effect by moving the light around the subject and also varying by varying the vertical angle between the light and the subject.  There are 3 sets:

  1. the light is horizontal in relation to the subject;
  2. the light is elevated and pointing down at 45 deg; and
  3. the light is directly above the subject.
This is best illustrated in the lighting diagram below which shows the basic positions.

My very patient model for the this was a mannequin head, which I felt was ideal for looking at the way light is shaped around a persons face.

Light horizontal

With the exception of the light being directly behind the subject, I kept all settings the same, as I felt this would best illustrate the effect, including the amount of light falling off the face of the subject.  The Speedlite was at 1/2 power and the camera settings were ISO 100, f/11, 1/125 sec.  Where the light was directly behind the subject, because I was shooting not only through the softbox, but also through the white backdrop, I increased the power setting on the Speedlite to full power.  The camera setting stayed the same.  Focusing was set to manual and lens stabiliser was off as I was using a tripod.
Front                                                       Right 45 deg,                                           Right 90 deg
In the set above, the first image is with the softbox as close to the camera as possible in the same plane.  It still was slightly to the right of centre, as evident by the shadows visible on the left.  The ideal would be for there to be no shadows at all.  As the light moves to the right, the amount of shadow increases on the face.  At 45 degrees, this provides a good modelling light revealing the form.
Right 135 deg,                                          Back                                                    Left 225 deg
As the light source moves towards the back there is more of a rim lighting effect, separating the subject from the background.  As there is somewhat less light falling on the background, it gets darker, showing how the action of the light can usefully alter the tone of the background.  With the light at the back, a silhouette is formed showing the shape of the subject.  I did have some light spill, as I did not use black 'stoppers' either side of the subject to kill such spill.  Moving the light to the left of the camera, in the last image of the trio above, this provides an interesting lighting effect, as the face is turned to that side.  The left of the face is lit with this side light giving a good sculptural effect and some drama.
Left 270 deg,                                                Left 315 deg,                                                              Front     
The first of the images above is displaying, what is referred to as "Rembrandt" with the light on the right in the shadow.  This is not true Rembrandt light, as it should be more pronounced and the light elevated.  Again, the form of the face is well shown.  The centre image now has more light on the face, and elevated, would be a good portraiture one-light setup, if elevated.  Finally, I managed to squeeze the softbox more effectively against the camera and the flatness of the lighting can be seen.

Light elevated and pointing down at 45 degrees

For this sequence, I changed the camera settings to ISO 100, f/8, 1/125 sec., adding an extra stop exposure due to the increased distance of the light from the subject.
Front,                                                      Right 45 deg,                                              Right 90 deg
Due to the angle of the head, when the light was above the camera, in front, there are shadows developed on one side of the face, so the lighting is not as flat as it otherwise would be.  At 45 degrees to the subject, there is considerable shadow to one side of the face, but the features are well modelled.  Withe the light side on, most of the features are hidden by shadow, so this would not be a particularly useful lighting setup.

Right 135 deg,                                              Back, above                                             Left 225 deg
The first of this sequence is not really helpful at all.  from the back, there is too much light for a silhouette, but there is good separation.  Throwing some light back using a reflector would make this useful.  There is already some light being thrown up from the white background paper on which the head is standing, as can be seen from the light areas under the chin and nose in particular.  Moving to the left, this has the makings of a Rembrandt style lighting.

Left 270 deg,                                    Left 315 deg
The final two in the sequence, as I did not retake a shot from the front.  The first is very much a Rembrandt style light, with the triangular light area within the shadow on one side of the face.  The second of these, provides a good modelling light, with a butterfly shadow developing under the nose.

Light directly above the subject

The camera setting for these was ISO 100, f/11, 1/125 sec.

Above                                              Above and back                                          Above and front
Of the 3 in this sequence, the last, with the light above and slightly to the front is the most useful.. It provides good shaping and ' due to the shadows falling of the cheekbones, gives a more slender look.

In terms of choosing which lighting setup reveals the form of the subject best, then I would go for the light to the left at 315 degrees.  This is an extension of the Rembrandt light, but the face has been opened up due to less shadow, which now creates a more sculpting effect on the opposite side to the light.


Saturday, 22 June 2013

Exercise: Softening the light

Bare bulbs of whatever kind, and in this I include Speedlites without any modifiers, create harsh light, which might be the intention, however not in this particular exercise.  Harsh lighting is typified by hard, dramatic shadows, whereas soft light can be seen through soft shadows and lower contrast, creating a more flattering light when used for portraits.  Such diffused light, for example, is great for hiding or disguising facial skin imperfections as well as providing a source of light which starts emulating an outdoor light.

Softening the light is achieved by means of placing some form of diffusion material between the light source and the subject.  The larger this diffuser is and the closer it is to the subject, then the softer the light.

For this exercise I used a small diffuser, referred to as a softbox (60cm x 60cm) which I had purchased on eBay some time ago.  Whilst not comparable to the larger and better softboxes from sources such as Lastolite, it still does the job. This I fitted to a Canon 580EX speedlite.

The exercise suggests that, depending on the subject, the light should be located above the subject.  I considered that this would be suitable for my subject, my Pentacon 6TL camera, which I have had since my college days, 40 years ago!  This is a 6x6 camera taking both 120 and 220 roll film.

I rigged a boom to suspend the light, though somewhat precariously, above the subject, though I had to hold it up once I added the diffuser.  The flash was controlled remotely using a Yongnuo wireless remote control system.  This is manual only, but as I tend to use flash manually, then this is not an issue.

I find that these triggers seem to work without any problems, both indoors and out, as well as at considerable distances.

All my metering is done using a Sekonic flashmate.  I take incident light readings as this removes, in the main, reflectivity, colour and tone issues which would affect reflected light readings.  My camera is set to manual and I find that this combination works really well.

The initial set, with no diffuser is shown in the diagram below.  The Speedlite was set to half power.

The result is below
ISO 100, f/16, 1/125 sec
Very evident in this image is the characteristic harsh shadow, with quite a sharp edge, even though the light was only about 70cm from the subject.  There are distinct highlights, in particular those running along the top of the lens and along the side of the pentaprism.  Also evident is the texture in the black surface covering for the body and prism.  This is a high contrast image.

Adding a diffuser changes the image quite considerably:
ISO 100, f/8, 1/125 sec
The two main differences which are immediately noticeable are the much smaller and diffuse shadow and the lack of sharp highlights which characterised the image without the diffuser.  The texture is still visible, though not as highly defined as in the first shot and overall this has lower contrast.  Adding the diffuser cut the light level by 2 stops.  I could not get a precise match between the two images and felt that the one with 2 stops difference was closest.  Opening up the aperture, also reduced the depth of field and this is also evident in the second shot.  To balance everything, I should have increased the power setting of the flashgun to 3/4 power or even to full power.

This exercise clearly shows the difference between a naked light source and one which has been softened using a diffuser.  How this effect is applied, depends very much on the subject matter and what is wanted as an end result.  

Photographic Lighting: Reading material

There are a huge number of books dedicated to this subject and I just don't know where the market is! I had acquired a couple of such books many years ago, and though they might be outdated and the poses / dress might not be particularly fashionable, they do provide some sound information regarding basic lighting setups which are equally applicable whether you use tungsten, studio flash or portable flash such as Speedlites.  In my case, I use Speedlites.

The first book I wish to refer to is "How to control & use Photographic Lighting" by David Brooks.  My copy from the early 1980's was published by HP Books, and searching for the title revealed that it was updated in 1989.

The early chapters discuss the effects of the light source and the light direction and reflection.  Very relevant and helpful for this part of the TAOP module as it supplements and enlarges on the course text.  The description is clear and helpfully illustrated.  The chapter relating to equipment is very dated, and whilst principles are fine, its probably best ignored as far more information can be obtained from other sources.  There is an extensive chapter on photographing people.  This I find a very useful starting point for a variety of lighting situations and complexities including natural, window, light.  All are well illustrated with lighting diagrams and resulting images.  The final chapter discusses lighting for "things".  Again well illustrated and extremely useful as a starting point.  Shooting glass and shiny objects are both subjects which are well dealt with.  Overall a useful book which can be acquired quite cheaply.

My next book is "50 Portrait lighting techniques for pictures that sell" by John Hart published by Amphoto.

Again my copy is from from 1983, but it was updated in 1995 and that copy is available from Amazon for £0.01 used.  That would be a tremendous buy.  This is clearly outdated, but as with the previous book, it is a good starting point for "50" different lighting setups which are well discussed and illustrated, both with photos and lighting diagrams.  There is nothing, here, though, which hasn't really been covered by the previous tome.  The message is, that a well executed and lit portrait will succeed in its aim.

At a photo exhibition a few years ago, I succumbed to obtaining "Portrait Photography Secrets of Posing & Lighting" by Mark Cleghorn and published by Lark Books.  I had just been watching him demonstrating various lighting techniques and the book was on special offer :-).  Mark Cleghorn is a Fellow of RPS and has many other distinctions and awards.  He certainly knows his stuff as I saw from his demonstrations.  The book runs through many styles and techniques and will provide the basic knowledge and inspiration to get going with taking portraits.

Studio work is something which I am interested in, particularly as the lighting is under your control, so the challenge is really how to use it in a creative way.

Alongside the books above there are the technical manuals which come with the kit.  In my case the Speedlites 580EX and 430EX II and the Nissin Di866 II.  It is definitely worth reading these if for no other reason than to become familiar with the controls.

What I have found is that, other than to become familiar with the subject, there is no substitute for practice.