Photogrammetry

1. New Ideas in Scene Diagramming Photogrammetry

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 20th , 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.

8. 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. iWitnessPhotogrammetry 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 Camera

29. The Scene…..

30. Photographing the Scene using Angles.

31. Did I mention Angles?

32. Taking the photos Left side of the road Right 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 20th 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

40. Crime Scene

41. Crime Scene • 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.