Download presentation
Presentation is loading. Please wait.
Published byDiane King Modified over 9 years ago
1
New Ideas in Scene Diagramming
2
What Photogrammetry is about. Photogrammetry Photo = Recording Light Grammetry = Measure ○ Measurement using photographs. Benefits Highly Accurate Preserves the scene at the time the photos were taken Gets the investigator out of harms way quicker
3
What Photogrammetry is about. Downfalls Extra training is required to complete the diagram Instead of time spent at the scene measuring, the time is spent at the computer mouse clicking.
4
What Photogrammetry is about Has been proven to open/clear scenes quicker allowing traffic to clear in less time. Less traffic backups mean less secondary collisions. This is the Basis for IN-TIME Indiana-Traffic Incident Management Effort.
5
Since June 20 th, 2009. Indiana has used Photogrammetry 29 times. 27 uses involve roadway closings 6 crime scenes have been measured 42 minutes is the average time it takes to measure a scene using Photogrammetry. 2 Hours and 13 minutes is the average times to use total station to measure a scene. (estimated) Means: 1 hour and 31 minutes saved. If it takes 4 minutes to resume normal traffic – around 9868 minutes would be save to Indiana Motorists. 1:31 = 91 Min * 27 scenes = 9868 minutes saved.
6
What Photogrammetry is NOT Voo Doo Science New 1) Ideas have been around for quite a while 2) Principles have been proven under Fry and Daubert Not the old “Vanishing Point” Method We are in the computer age. Not Photo rectification or Flattening an Image to diagram.
7
Compared to other measurement systems.
9
What you need for Photogrammetry Camera Tripod Memory Cards Targets iWitness Software CAD-software (Crashzone recommended) Tape Measure For more advanced – Smart level Flashlight
10
Camera More than a 6.1 MP camera Indiana State Police uses a 10 MP Olympus Camera Requirements Must be able to turn off Auto Focus Must have a Manual Mode Chip size does make a difference Point and Shoot vs D-SLR. Relates to night scene quality and overall image quality.
11
Cameras Point and Shoot vs Digital-SLR (DSLR) Think of sensor size and quality, bigger sensor – better quality
12
Camera I have tested…. Nikon D90,D70, D100, D700, D3 Canon 1d II, 5D, 5D II, G9 (P&S) Sony Olympus E-420, E-520 Nikon Point and Shoots: sj1000pj
13
Tripods Hold the camera steady for night and low light shooting. Any will work Make sure the specks say they will hold the cameras weight.
14
Memory cards. Hold the images taken at the scene. Anyone will work
15
Weighted and Cone Targets
16
Cad Software
17
Tape measure Needed to measure 2 scale distances
18
iWitness Photogrammetry Software MS Windows base software for measuring and modeling OBJECTS or SCENES. Uses digital images to mark (X,Y,Z) coordinates for use in CAD software to diagram scene.
19
iWitness Photogrammetry YOU do not have to know the MATH involved in determining these points. YOU only have to know how to see the point, photograph the point, and click a mouse in various images.
20
Photographing the Scene Pictures must have good angles between each other The same point must be photographed using different angles. Look at the cones in the next slide… Same cones, different angles…
21
Photographing the Scene
22
Nuts and Bolts of Photogrammetry Cameras see 2D images in a 3D world.
23
Nuts to Bolts (Cont) Photogrammetry brings back the 3D world out of 2D images Images MUST be taken in a certain way then This is a simplified way to think of photogrammetry. This is not the math utilized in iWitness or an attempt to show the math in the program.
24
Photos of Same object from different angles.
25
These two lines are the same line in different photos.
26
These lines are REFERENCED to the same markers we have placed in the scene in different photos.
27
What do Angles have to do with it? A camera can only see 2 dimensions With the same point referenced in different pictures, shot at different angles the computer can do a “triangulation” to get the EXACT point in 3d space.
28
Angles Camera
29
The Scene…..
30
Photographing the Scene using Angles.
31
Did I mention Angles?
32
Taking the photos Left side of the roadRight side of the road
34
Crashzone Work
36
Timeline (Rounded) Arrive at scene - 3:00 pm Walk and investigate scene Start Photos - 3:22 pm Finish Photos - 4:02 pm Release scene to Wrecker Wrecker off Scene – 4:32 pm Time Road Closed – about 1.5 hours. Above using ISP stats since June 20 th 2009.
37
Remember There is still work to be done doing the diagram away from the scene. ○ Officer is safer -Paper Cut vs Run Over -Climate Controled -Stress free ○ Roadway is opened and flowing sooner ○ Less Secondary Collisions!!!!!
38
Photogrammetry Questions HOW ACCURATE Depends on the number of photos taken Accuracy under MY CRASH SCENES Most Accurate 1/8” over 1000 feet Least Accurate 1 Inch over 500 feet ○ 2nd scene before actually being trained in its use
39
Crime Scene
41
I was sent 8 Photos of the scene Camera was not calibrated and the Camera was auto-focusing.
42
Measurement Reported to me was 50 Inches. Reasons for.3390 of an INCH - Round Error?
43
Another Case Study.. November 27th, 2008 at 11:30 PM. I-65 NB at 241 MM, 1 Vehicle Fatal Crash Northbound vehicle loses control and goes into the median. Flips end over end and comes to rest against SB guard rail. 2 occupants ejected; one in median and one on SB traffic side.
44
Another Case Study.. November 27th, 2008 at 11:30 PM. Roadway closed for approximately 1 hour. The at scene trooper painted the roadway to mark scene Reconstructionist did not go to scene that night as I was more than an hour away.
45
Another Case Study.. November 28th, 2008 at 11:30 AM. Went to the scene to measure Took approximately 1 hour to photograph the scene as the family arrived on scene for an explanation of the crash. Time the roadway was closed to measure scene...
46
Another Case Study.. November 28th, 2008 at 11:30 PM. IT WAS NOT!!!!! NO CLOSURE. The following diagram was completed.
47
Scale Diagram of Scene
48
IN 3D – Using Crashzone Corners of Highway sign
49
Costs….. Camera – Around $500.00 + Calibration Targets – $89.00 Tripod – Around $50.00 Memory Cards – $20.00 Targets – $450 to 610.00 iWitness Software – $995.00 to $1995.00 CAD-software (Crashzone) – $695.00 Tape Measure – $10.00 For more advanced – Smart level – $45.00 Flashlight – $50.00 Total = $3064.00 as listed
50
websites….. Camera – Various Calibration Targets – www.iwitnessphoto.com Tripod – Various – Amazon, etc Memory Cards – Camera Stores etc. Targets – www.iwitnessphoto.com iWitness Software – www.iwitnessphoto.com Crashzone – www.cadzone.com Tape Measure – Home Depot, Menards, etc For more advanced – Home Depot etc. Flashlight – anywhere to issue.
51
www.iwitnessphoto.com www.iwitnessphoto.com ○ Lee DeChant Consulting Inc. ○ Sole Source in North America ○ iWitness Software, targets www.cadzone.com www.cadzone.com ○ Anna Ristau is Law Enforcement Contact ○ Crash/Crimezone S/Trp Thomas W Quinn ○ Indiana State Police ○ 219.405.5507
52
Finally…… All of this software requires training. Indiana has 6 trainers in photogrammetry ○ 5 ISP Troopers ○ 1 Boone County Deputy
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.