Category: Motion Lapse Photographs


I have made a lot of mistakes in the last four days and learned valuable lessons about AgiSoft StereoScan, the free program I am using to convert stereo photographs into 3-D meshes. I noticed a problem that when I blended the photos in Photoshop first the floor often melded with the material and StereoScan treated it as a floor plane. Download the 3-D model.

StereoScan lessons

StereoScan lessons

After a lot of trial and error, I found a way to blend multiple photographs and build a 3D model in StereoScan. I ended up manually selecting and deleting everything except the illuminated material in each layer of the sequence. Then StereoScan could map the volumes of the multi-frame packet.

stereoScan volumes

stereoScan volumes

This is the method for converting stereo pairs of photographs into a 3D model:

  • Record synchronized stereo photographs.
  • Manually delete everything in the frame except the illuminated material.
  • Load the blended left and right images into StereoScan
  • Create a 3-D model

The models may, of course, be imported with other programs. I used Rhino with V-Ray to make a quick render of one of the simplified surfaces.

Rhino with V-Ray render of original form

Rhino with V-Ray render of original form

Rhino with V-Ray render of rebuilt surface

Rhino with V-Ray render of rebuilt surface

I’ve summarized my current thoughts on the history of similar photographic methods by Etienne-Jules Marey, Eadweard Muybridge, László Moholy-Nagy and Annie Halliday. Included are ephemeral models from the most recent modeling session with Elizabeth Turner and some tests of how to transform this information further.

Process, research and tests

20110327_libraryWallPinch

20110327_libraryWallPinch by Laurie McGinley

20110327_libraryWallPinch, originally uploaded by Laurie McGinley.

Elizabeth Turner is a classmate who is working with Great River School for her Master Final Project (MFP). She is also a friend who sits right next to me in studio. On Friday morning we were talking about our projects and other exciting topics when she said, “I want to model my design with your camera.”

Elizabeth recruited four students and our MFP coordinater, Gayla Lindt, to help us model her project last night. You may view more photos from this session on Flickr.

Blended image of an ephemeral model made with a 18’x5′ piece of white ripstop nylon, a Lowell Omni studio light, a two tube fluorescent shop light and eight people. Model designed by Elizabeth for her Master Final Project work at Great River School.

Many thanks to Gayla, Elizabeth, Abby and four amazing students for helping make this model. Thanks to Amber for the use of the fabric.

20110322_threePointFlex

20110322_threePointFlex by Laurie McGinley

20110322_threePointFlex, originally uploaded by Laurie McGinley.

Blended image of a model made with a 18’x5′ piece of white ripstop nylon, a Lowell Omni studio light, a two tube fluorescent shop light and four people.

This image fascinates me. I can’t exactly explain why the right half of the frame is red. My best guess is that it is an artifact of the Photoshop script that blends the photos together. The light source for this series is on the right side and was very bright. Maybe the contrast in the intensity of light between the two halves of the frame contributed to the red color.

Many thanks to Amber, Dan and Erin for helping me make this model.

Inverted, blended image of a model made with a 18’x5′ piece of white ripstop nylon, a Lowell Omni studio light, a two tube fluorescent shop light and four people.

I inverted this image after I blended it. The result of inverting a photograph made after dark in Rapson Hall courtyard is that the illuminated materials, the fabric in this case, appear as solid, substantial materials. It is possible to create and experience a digital model with little more than a light and any material.

This photograph reminds me of Kenn Kotara’s screen sculptures.

Many thanks to Amber, Dan and Erin for helping me make this model.

20110322_fabricSquare

20110322_fabricSquare by Laurie McGinley

20110322_fabricSquare, originally uploaded by Laurie McGinley.

Blended image of a model made with a 18’x5′ piece of white ripstop nylon, a Lowell Omni studio light, a two tube fluorescent shop light, four people and time.

My camera is set up in a way that photos made in Rapson Hall courtyard after sundown look very dark. As a result, anything that is illuminated appears very clearly in the photographs. The camera is programmed to make a frame every three seconds and each exposure lasts a mere 1/15th of a second.

This cadence allowed us to place the fabric, light it and move it before the next frame was made. I just edited these individual frames into blended photos. The blended result of placing the illuminated material all over the courtyard is a model.

Many thanks to Amber, Dan and Erin for helping me make this model.

20110317_shopApartment

20110317_shopApartment by Laurie McGinley

20110317_shopApartment, originally uploaded by Laurie McGinley.

Inverted image of a model of my apartment made with a 4′ x 3′ light box, motion lapse photography and time

I have been making models in Rapson Hall courtyard for the last week that only a blended, motion lapse photograph can portray. For this model I stood in the empty courtyard and remembered the layout of my apartment. Using a 4′ x 3′ light box, I recreated the spaces of my apartment one frame at a time.

There is a challenge in making these models out of light, time and blended photography; the model was made one frame at a time and each frame is three seconds apart. The shutter only opens for 1/15th of a second each time and I have three seconds to move into a new position for the next photograph.

Unilke light painting when a long exposure is used to represent a light moving through space, these are short exposures. A 1/15th second exposure is just long enough to be able to show a little movement if you are moving fast.

As a result, these models are created patiently over a period of time. This model took 9 minutes and 21 seconds to complete and is comprised of 187 individual frames.

model made of light and time
shop light

model made of light and time
Festivus pole

20110216_definedRoom

20110216_definedRoom by Laurie McGinley

20110216_definedRoom, originally uploaded by Laurie McGinley.

Light model imposed over captured activity.

Tech 2 review preparations

Three meter light pole defines center square of courtyard

Powered by WordPress | Theme: Motion by 85ideas.