Crime Scene Photography

In order to be admissible in court, photography has to be…

1. relevant

2. material/impactful

3. fair and accurate representation/authentic

What is relevant evidence

evidence having the tendency to make the existence of a fact more or less probable than it would be without the evidence

Digital Single Lens Reflex (DSLR) Camera

Uses a mirror and optical viewfinder, look through lens with your eye, can use interchangeable lenses. big/bulky/hefty

Mirrorless Camera (6)

Smaller and lighter. Direct to sensor viewing, live exposure, simplified mechanism and shutter systems. better frames per second. resolution.

Pros of Mirrorless Cameras (6)

Size/weight, resolution, real time exposure, shift of technology, longevity and video

Cons of Mirrorless Cameras (4)

Expensive, viewfinder issues, focus on low-light and battery life

Auto (Green Box) Mode

Camera decides settings

Program (P) Mode

Photographer sets the ISO, camera sets shutter and f-stop

Shutter Priority (Tv) Mode

Photographer sets shutter, camera sets ISO and f-stop

Aperture Priority (Av) Mode

Photographer sets f-stop, the camera sets ISO and shutter

Manual (M) Mode

Photographer sets all settings

International Organization for Standardization (ISO)

The camera’s sensitivity to light

ISO of Exam-Quality Photos

100

ISO of Outside Photos (bring sunny day)

100

ISO of Everyday Photos (morning, evening, indoors)

400

ISO Painting with Light/Nighttime

800

F-Stop

lens setting that indicates the size of the aperture and controls the depth of field (what is in focus) and how much light is let in.

Higher F-Stop (f/22)

smaller aperture, less light, larger depth of field

Smaller f-stop (f/4)

larger aperture, more light, smaller depth of field

F-Stop of Everyday Photos

f/8-11

F-Stop of Exam Quality Photos

f/11-f/22

F-stop of Nighttime Photos

f/4-5.6

Shutter Speed

The length of the time the cameras shutter is open.

The faster the shutter…

the less light enters the camera. can freeze action.

The slower the shutter…at 1/15 or slower…

the more light and blur can occur. can eliminate rain and snow at 1/15 or slower.

For a standard 50mm lens, what’s the slowest the shutter should be while holding the camera?

1/60

For ariel photography shutter should be…. or ….

1/500 or 1/1000

Shutter for painting with light/Bluestar/laser photography

Bulb

Camera Eye Analogy: F-Stop

F-Stop=Pupil Dilation

Smaller pupils allow u to see further and clearer. At night your pupils are larger to let more light in.

ISO Camera Analogy

ISO=Eyesight at night

Your pupils are larger allowing you to see , but eyesight is grainer

Camera Analogy Shutter Speed

Shutter Speed=Blinking

Shutter speed, aperture (f-stop) and ISO should be adjusted to…

the ambient lighting to ensure pictures properly exposed

Theory of Reciprocity

States that a variety of f/stop, ISO, and shutter speed combinations result in the same exposure

UV/Haze/1A/Skylight Filters: 2 Common Uses

Lens protection from dropping/damaging camera.

Filtering excessive blue from sky

Polarizer Filters: 3 uses

Can eliminate reflections (water, windows), enrich color saturation, and make skid marks more obvious on scene

Colored Barrier Filters: When are they used?

Used in conjunction with a alternative light source (ALS)

Wide angle lens

focal length shorter than 50 mm

Compared to a 50mm lens, wide angle lenses have (3)

1. broader field of view

2. increased depth of field

3. elongate distances from foreground to background

Telephoto Lens

a focal length longer than 50mm

Compared to a 50mm lens, Telephoto lenses (4)…

1. magnify distant objects

2. have a narrower depth of field

3. compress distances from foreground to background

4. shallower depth of field

Marco Lens

Designed to magnify small objects so they will fill the frame of the photograph making them ideal for comparison photography

Abberations

Defects in an image produced by a lens, account for a reduction in resolution

Diffraction

the bending of light when it strikes an edge, causes loss of resolution, sharpness, and clarity

Distortion: 2 Types + their lens

1. Barrel Distortion: Wide-angle lens

2. Pincushion Distortion: Telephoto lens

Barrel Distortion

The effect of using a wide angle lens that results in straight lines appearing at the edge of the image bent outwards

Pincushion Distortion

An effect of using a telephoto lens that results in straight lines appearing at the edges of images bent inwards

3 Cardinal Rules of Photography

1. Fill the Frame

2. Maximize depth of field

3. Keep the Film Plane Parallel

Keeping the Film Plane Parallel

Keep back of camera parallel to surface of item being photographed. AKA keep the length of the lens perpendicular/90 degrees to the surface

Memo Sheet Information (4) Log

1. Camera Settings

2. Subjects Photographed

3. Marker Numbers

4. Specific Variables for each digital image (lens type, flash settings)

Overall Photographs

Documents overall conditions of the crime scene in relation to area around it. Taken in a natural perspective

Midrange Photos

Used to show relationships between item of evidence and a fixed feature within the scene previously photographed in overalls. The item, fixed feature, and photographer should form a triangle

Close-up Photos

Photo of individual item of evidence, filling the frame of the photograph

Body Panorama (10)

1. Full face

2. Full body

3. Upper half

4. Hands

5. Lower half

6. feet

7. injuries

8. back/front shot

9. All four sides

10. Additional photos based on case

Vehicle Documentation: Exterior Pictures

1. One from each side(4)

2. One from each corner (4)

3. VIN/tag (2)

4. Other identifying features: damage, decals/stickers, evidence seals

Vehicle Documentation: Interior Photos

1. Door panel/interior compartment

2. Dash/steering wheel

3. Trunk/hood

4. Center console/ glove box

Exam Quality Photographs

Any photographs that will be used for comparisons that require specific settings to ensure best quality

Exam Photo Format Settings (2)

Uncompressed or lossless format (TIFF or RAW)

Exam Photo Camera Angle

90 degrees to the surface being photographed

Exam Photo Mode (2 options)

Manual or Aperture Priority Mode

Exam Photo F-Stop

between f/11-22

Exam Photo ISO

As low as possible to prevent noise from obscuring detail

Exam Photo Shutter Settings

Use tripod and adjust shutter as needed

Exam Photo Labeled Scale Plane

Labeled scale on the same plane as item being photographed

Exam Photos for 3D Impressions

Hot shoe cord needed for 3D impressions

Blue star

A chemical used to detect hidden traces of blood

Blue star Photo Procedure

1. Mount camera on tripod and set to manual

2. Photograph area under normal lighting conditions and standard settings

3. Focus camera while lights are on, then switch to manual focus

4. Adjust settings for low-light exposure

5. Begin exposure and apply Bluestar

6. Bounce your flash at the end of exposure

Bounce Flash

Flash is aimed at ceiling or wall instead of item/subject

Fill Flash

Used when parts or scene are lit with strong ambient light and others have heavy shadows or are black lit

Oblique Flash

Side lighting that creates shadows making it easier to see the 3D aspects of the pattern

UV Photography is useful for…

screening biological fluids, fibers, and photographing fingerprints processed w dye stains or deep muscle bruising

UV light procedure

similar to blue star but you need a barrier filter to block U.V. light

IR PHotography is useful for

documenting bloodstains or GSR on dark surfaces and for visualizing ink variations or writing on burned or altered documents

To effectively capture IR images: (2)

1. Use a camera specifically modified to be sensitive to IR light

2. Attach a Wratten 87 filter to block visible light and isolate IR spectrum