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Image Manipulation

April 20, 2010 Leave a comment

Hi, open up the image of the lady and the dress and the rest of the images.  The links are below.  Click on the links to open the images except for the Dress link.  Right click on that one and select  Save As

Model

Dress Right click and select Save As (this is a Photoshop PSD file that needs to be saved before opening)

wallpaper

walltexture

tile

ball of lightning

Deviantart is also a good source of images.

http://foxstox.deviantart.com/gallery/#Industrial

With the image of the lady open.  Use your magic wand tool, or the quick select tool to select the background.  Once selected inverse the selection.

by inversing the selection you have now selected the lady.  Press [Contrl J] to make this selection its own layer.

You can also use Edit/Copy and Edit/Paste

Now open the Dress image.  You will notice that the dress has already been cut out and that the background shows a chekcerboard pattern.  This means that the background is transparent.

Using your Move tool, click and drag the dress from its document onto the image of the lady.

You’ll notice that the dress is much too big.  with the Move tool still selected.

Go to Edit/Free Transform and click and drag on any of the four cornders of the bounding box that appears.  Make sure to hold down shift to scale the dress proportionately.

Now that you have sized the dress.  Make a copy of the dress.  Go to your Layers Window and duplicated the layer and place one of the Dress layers on top of the lady and the other below the Lady.  You’re Layers should look like this.

Make sure you are on the top most Dress layer and go to Edit/Transfrom/Warp.  This will create a bounding box with handles that you can manipulate.

Once you have the Warp bounding box up.  Drag the lower right corner over to create layers in the dress.

Manipulate the handles to get a feel for how this moves, you will also have to make sure not to warp it too much.

Dont worry about the parts where it looks like the dress has disapeared, it is still there.  Accept the changes. to view them.

Create a new Layer above the lowest Dress layer but below the layer the Lady is on and on this layer paint black on top of the dress to shadow it.  Turn the layer to multipy and adjust its opacity until you achieve the desired results.  See the image below.  As you can see the image on the right has shadowing applied to it, and it looks more realistic.

Before we go too far on her, we should add some atmosphere to this image.  I added the walltexture image and used a multiply blending mode.

Next I added the wallpaper textrue to the background to create a wall.  As you can see I layered two of them on top of each other.  Below you can see them.  One is a Multiply blending mode, the other is a soft light blending mode.

Next I am going to add another layer of texture to the floor.  I am going to add a tile texture.  and then distort the tile so that its perspective works with the image.

To do this go to Edit/Transform/Perspective

Adjust it until it is correct.  As you can see once again I used two layers blended on top of each other.  The bottom layer is multiply while the top layer is soft light.

And last, to add a sci fi element we will add a ball of lightning to her left arm.  Open the ball of lightning image and drag it into your document.  Make sure it’s in the top most layer and go to Select/Color Range and with the color picker chose the color black on the ball of lighting.  Hit ok and then Delete on your keyboard.

You have now deleted only the black color in the image.  Move it so that its over her left hand and adjust the blending mode until you find one you like.  I personally liked Linear Dodge.

However the ball is too pink, use an adjustment layer to change the color to a more yellow red to match the rest of the image.

It still looks pasted on.  If she really was holding a ball of lightning we would expect light to fall on her and the scene.  To do this we will add a lighting effect.

Create a new layer and fill it with the color white.  To fill the layer use the Fill tool

Make sure you are in RGB mode then go to Filter/Render/Lighting Effects

Create something that looks like what you see below.  Keep in mind that you want the lightning ball to be the source of the ligth.

Then adjust the blending modes and opacity until you get a result you like.

With some twiking Hard Mix at 68% Fill seemed a good choice.

Here is what we started with.

Here is the final image

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Flash

March 12, 2010 Leave a comment

Your camera probably comes with a built in flash.  In low light situations when you’re indoors or outside at night you may have to use your camera’s flash to light the scene.  However, don’t rely too much on it because it tends to wash out colors.  In indoor situations it may be best to just up your ISO to above 800 so that you are able to shoot at a fast enough shutter speed to capture motion and get  correctly exposed images.

One good thing to know regarding light is the Inverse Square Law.  The farther that light travels, the more the more the light rays spread out and the dimmer the resulting illumination.

The law states that at twice a given distance, an object receives only one-fourth the light (intensity of illumination is inversely  proportional to the square of the distance from light to subject).  In the image below, only one-fourth of the light falls on an object at 10 ft as from the same light source at 5 feet.

Keep this in mind when using flash as your primary light source, it will not illuminate everything but dicipates rather quickly.  However, in bright daylight you may want to consider using flash for effect.

Check your camera manual for the the distance your flash will reach depending on your f/stop.

Also, check your camera for different Flash modes.

If you have a subject in front of a bright background, you can use Flash Slow Speed Sync (if your camera has that mode) this sets the shutter speed slower while using the flash to capture both the background and the person clearly.

Use Trailing Curtain Sync

Below is an image shot with the Flash in brigth daylight.  Compare that to the image shot without the flash.  Notice how even in bright daylight when there is plenty of sun to give us a rich colorful image, the one with the flash is washed out.  However, notice how the flash has filled in the areas where there would be shadows, this gives us detail in the shadow areas but robs the image of depth.

The Image below was shot with no flash, notice the colors are richer.  However, notice that the shadowed areas dont have as much detail.

When your flash is up in Manual Mode, your camera will probably give you minimal control over your shutter speed.  More than likely when your shutter is up your camera will set the shutter speed for you.  My camera in Manual Mode locks my shutter speed at 180th of a second.

However, I still have access to my aperture to control the light coming into my camera.  You can use this to fill in areas of really dark shadows on an otherwhise bright scene.

While in Manual Mode and with the flash up, meter the scene to what your camera tells you is correct.  For this scene it was

Shutter Speed 180th, Aperture f/8

Then stop down and see what happens to the image.  The image below was shot at f/11.

Keep stopping down.  f/16

f/19

f/22

f/27

f/38

Not every image is a winner, but at f/19 or f/22 we get a nice effect while using flash in brigth daylight.

Use this with people outside on a bright day.  Or if you have access to multiple people place the people at different depths with in the picture frame and notice how you can create depth by how far the flash will reach.


Categories: Flash

White-Balancing Yoda

March 4, 2010 Comments off

Here is a quick example of how the dominant color of your light source affects your photograph.  The image of Yoda below is white balanced to 4200K.  In the Color Temperature Spectrum (image on the rigth) that’s a Warm Flourescent light shource.

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Next I set up two flashlights each with a color gel on them.  The colors are simple Red and BLUE.  Without changing the color balancing  I turned on the blue light.

BLUE LIGHT SOURCE

Blue Light Camera set at 4200K.  As you can see the image has a slightly bluish tone.

Set the camera at 2500K from the Color Temperature Spectrum above, I white balanced for a dominat redish light source.  As you can see by white balancing for a redding light source even though we have not changed the color of the actual light, red gets taken out and we have an even bluer toned image.

Set the camera to 10,000K.  By white balancing for a dominant blue light source we take out Blue and the once bluish light is not a reddish brown color.

I repeated this with Red.

RED LIGHT SOURCE

Red light source shot at 4200 K.

Red light source at 2500K.  Notice how by taking out the red from a scene with a dominant red light source the image as a whole has a mangenta hue and the shadows take on a very blue hue.

Red light source white balanced at 10,000K.  By taking out the Blue, white balancing for blue, the whole scene takes on a red tone.

Next I turned both the Blue and the Red light on and shot it at 4200K.

BLUE and RED LIGHT SOURCES

Then shot it at 2500K.  Notice how the ligth is much bluer now, also notice how in the hightlights in the background, where the white highlights start to fade into color on the image above it had previously leaned towards a yellowish color.  That is now Magenta on the image below.

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Shot at 10,000K the photograph takes an even Redder tone, and notice how now the previously blue light is green (left side), and the highlights in the background where the two lights meet blend off into yellow.

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Categories: White-Balancing Yoda

Color and Photography

March 2, 2010 Leave a comment

All colors can be created by mixing three primary colors.

The Additive Color system mixes RED, GREEN and BLUE light in varying proportions to match any color.  Television sets and computer monitors use additive color.   And your camera does too.

Notice how a GREEN and RED light make Yellow, while a RED and BLUE light make up Magenta (purplish color) and a GREEN and BLUE light together make Cyan.

Equal quantities of the three colors (RED, GREEN and BLUE)  appear White (if they are bright enough, otherwise they will lean towards neutral gray.)

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The Subtractive Color system uses CYAN (bluish green), MAGENTA (purplish pink), and YELLOW to match any color.   This is how paint works.   Each color absorbs (or subtracts) one of the additive primaries.

If you put CYAN paint on paper it removes Red from the White Light that shines on it and allows GREEN and BLUE to be reflected.

The CYAN paint absorbs the RED light that hits it and only reflects back to your eyes GREEN and BLUE.  Your eyes then Mix the GREEN and BLUE light reflected from the pigment and you perceive the color CYAN.

This is important because when you photograph anything, you want to be aware  that you see the world like your camera sees the world.

For example when shooting outside Midday light is more BLUE (cooler).  Early morning and late afternoon light is more RED (warmer).

When shooting inside with artificial lights.  Light from an ordinary bulb has a temperature of about 2800 K, proportinately less BLUE and more YELLOW and RED than daylight at 5000K.

We went over White Balancing in a previous post.

Your camera has the option to White Balance for the dominant light source.  Be that daylight or sunset or indoors: fluorescent or incandescent/tungsten light bulbs.

One reason to see like your camera as far as Light and Color is so that you start looking at your surroundings and determine what is the best time of day to photograph those places for whatever effect you desire.

The other reason you want to know how your camera see’s light is to capture skin tones correctly.  You can get away with not White Balancing your camera when you are photographing places, landscapes, objects, you can say, “I like that yellow hue I got by not White Balancing for the Tungsten light in my living room”  But if there was a person and you made them look orange because of it and it was not done for effect, then its just bad photography.

Keep in mind that one way to spot an amateur photographer, is one who doesn’t know how to properly white balance a scene.

Photography is not just about documenting a place or taking a portrait of a person, but also what mood or effect you are trying to achieve with your photograph.

Before we get to deep into thinking of how light affects your camera, we’ll go over basic color theory.

To the right is a simple color wheel.  From this simple color wheel we can find many easy to use color schemes.  These color schemes are tried and true and when used in your photographs will enhance them.

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Complimentary Color Scheme:  This is as basic as it gets, colors that compliment each other, colors on opposite sides of the color wheel.  BLUE and ORANGE, RED and GREEN, YELLOW and PURPLE.  Think of any NFL or High School Football Team logo and you will find Complimentary Color Schemes at work.  These colors go together well and when used in combination with a good composition can only enhance a photograph.

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The Triad Color Scheme is made up of colors equally positioned on the color wheel.  Triad color schemes gives you the opportunity to work with multiple colors and have them all work together harmoniously.

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The Analogous Color Scheme is made up of colors located adjacent to each other on a color wheel.

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Using the above color schemes wont guarantee a great photograph, but it will give you a photograph whose colors work well together.

Definition of Terms

Hue=Color, Hue is any pure color in the color wheel.  In terms of lights its equivalent to all the colors in the light spectrum, “all the Hues of the Rainbow”

Each idividual color on the color wheel, in the ligth spectrum, is a hue.

Saturation: Is the intensity of a color.  Colors/Hues can be saturated or desaturated.  This saturation is the intensity of that specific color.  That intensity is measured against Neutral Gray 50% Gray.  If you desaturate a photograph you have turned the photograph into a Gray-scale image.

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Categories: Color and Photography

Focal Length and Perspective

February 26, 2010 Leave a comment

The thing to keep in mind with your lenses Focal Length is that the shorter your focal length the wider your angle of view the Longer your Focal Length the narrower your angle of view.  This means that as you zoom in you will see less of the image.

Changing your Focal Length does not change the size of one object compared to another.

The images below were taken from the same distance from the subjects but changing the focal length.  Zooming in with your camera’s lens.

Perspective is controlled by the lens-to-subject distance, Not the focal length of the lens.

Keep your focal length the same, go to the short focal length your lens allows and move closer to the subject.  As your lens comes closer to the scene, foreground objects are enlarged more than background ones to give three different perspectives.   As the lens gets closer to the subjects closer to the lens get larger.

We judge depth in a photograph mostly by comparing the size of objects, so the depth seems to increase if foreground objects appear larger than background ones.

A long focal length lens used far from a subject produces a telephoto effect.  In the image on the right the crowd is compressed into a mass.

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A short focal-length used up close increases the apparent size of the part of the subject that is closest to the camera.  This is wide angle distortion.

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Depth of Field and Plane of Critical Focus

February 25, 2010 Leave a comment

In the previous Aperture lecture we went over to use your camera’s Aperture to control your depth of Field.

An f/stop of f/16 gives you more depth of field over an f/stop of f/2.

Another component of Depth of Field is the Plane of Critical Focus.

The Plane of Critical Focus is the plane were the lens is focused.

Depth of Field is the area in a photograph where the photograph is acceptably sharp (focused).

In the image below by Eli Reed you can see the Plane of Critical Focus. The people are in focus and the background and the man in front are out of focus.

Below is a diagram of the Plane of Critical Focus.

Below is the same image, photoshoped to emphasize a smaller depth of field.

Here is the diagram of the new lower depth of field.

Focus (depth of field) in your photograph increases faster behind the plane than in front.

Usually the depth of field  (objects acceptably in focus) extends about one-third in front of the plane of critical focus and two-thirds behind it.

Keep this in mind when you are really close to your subject.  The closer you are to your subject the less depth of field you have.

Shutter Speed, Exposure and Motion

February 16, 2010 Leave a comment

To correctly expose a photograph so that it is neither too dark or too light you need to control the amount of light that reaches the sensor in your camera.

There are two main things in your camera that you can control that affect the exposure of your photograph.

1: The size of your Aperture, which is the size of the Iris of your camera (this also controls your depth of field)

2: Shutter Speed, the length of time you allow the shutter in your camera to remain open, (this also controls motion blur)

Most Digital SLR cameras have a Focal-Plane shutter.  This consists of a pair of curtains usually located just in front of the sensor.  During the exposure the curtains open to form a slit that moves across the light sensitive surface.  The size of the slit is adjustable: the wider the slit the longer the exposure and the more light that reaches the sensor.

The slit moves across the sensor in much the same way that a copy machine or a scanner works.

This slit is your Shutter and the amount of time it remains open is your Shutter Speed.

Depending on your camera, it will display the Shutter Speed in seconds or fractions of seconds.

Depending on how you want your photograph to turn out, you will have to decide what Shutter Speed to use.

For example, a fast Shutter Speed of 1/250 of a second can capture motion well.  This means that your shutter remained open only for 1/250 of a second.  The photograph will freeze motion.

Where as a slow shutter speed 1/8th of a second will show most moving obtions blurry, otherwise known as motion blur.

Typical shutter speeds are:

2 sec, 1 sec, 1/2 sec, 1/4 sec, 1/8 sec, 1/15 sec, 1/30 sec, 1/60 sec, 1/125 sec, 1/250 sec, 1/500 sec, 1/1000 sec

However, some cameras only display the bottom fraction of the shutter speed and seconds are then displayed with quotation marks following them:

2″, 1″, 2, 4, 8, 15, 30, 60, 125, 250, 500, 1000

Below you will see some different ways that a camera will display the same shutter speed of 1/250 of a second.

There are a few ways to use Shutter Speed to show motion in your camera.  You can use a fast shutter speed to freeze time.  Typically 1/250 or 250th of a second is a fast enough shutter speed to freeze the motion of humans and most objects.  However, this is all relative to what you are photographing.  If you want to freeze the wings of a hummingbird you may have to go as fast as 1/8000th of a second to freeze its flapping wings.

A less drastic example of a bumper car is below.

The image to the right was taken at a 1/500 of a second shutter speed.  The motion of the bumper car has been frozen in time.  Notice how there is no motion blur.

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While this image was taken with the camera still but at 1/30th of a second.  The bumper car is just a blurr.  This is motion blurr.

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There are two ways you can take this image at 1/30 of a second shutter speed and show the subject (bumper car) sharp.  One way is to pan the camera with the motion of the subject.  This technique has the added effect that the background will be blurry due to motion blur, but your subject will appear frozen in time.  The key to making this or any action shot work is to anticipate the motion of your subject and follow it.

Think about what your subject might do next instead of focusing on what has already happened.

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One other way that this photograph can be taken at 1/30 of a second is to photograph it head on.  Because in this photograph the bumper car is moving straight at the camera, not enough of it crossed the recording surface to blur.  Whereas the bumper car on the lower left is going across the photograph and becomes blurred.

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One last note on Shutter Speed.  The length of your Focal Lens also affects how long of a Shutter Speed you need to capture even stationary objects without motion blur when you are hand holding your camera.  Typically 1/60 of a second is a good enough shutter speed for the typical lens that comes with most DSLR’s (18mm-55mm).  Though use at least 1/125 whenver possible.  Most Digital SLR’s come with an 18-55mm focal length lens.  Longer your focal length the more magnified an object is and it makes the object appear closer to the camera and the faster your shutter speed needs to be to avoid motion blur.   The rule of thumb is, if the ration of your focal length divided by your shutter speed is less than 1 than you are for the most part safe.  For example if you have a 200mm lens and are using a 60th of a second shutter speed, chances are that if you are hand holding your camera the image will be blurred.  If you are using a 200mm lens you would want to use at least a 250th of a second (1/250) shutter speed.