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| Introduction to 3D |
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Shooting 3D
The following steps are geared toward 3D computer rendering but, can be adapted for use with film, video or digital cameras. The render width is the size of the film or CCD array in the camera and cropping adjustments should be based on the camera's eye piece or display device. Using cameras will limit the flexibility of your imaging options from the stand point of set design, lighting and cropping. Maintaining the proper aspect ratio within the camera's view finder is very important if the finished image must be a particular size. Cameras require the use of a motion track that must be controlled in even steps between frames. Cameras are particularly useful in creating 3D backgrounds of landscapes and 3D product shots. Use of blue screen techniques can be utilized to combine camera shots with computer graphics. Film can be scanned using PhotoCD (Pro is best) or drum scanned. Video can be digitized and digital camera output can be used directly. The size, quality and resolution of digitized images should take into account the final trim size of the printed lenticular image. 1. Determine bleed and safe size. 1/8=0.125 2. Determine image trim size. 7 wide by 5 tall 3. Add bleed. 7.25 by 5.25 4. Calculate image aspect ratio. 7.25/5.25=1.38095 5. Determine total parallax. .75 6. Calculate render/capture width 7.25 +(2*.75)=8.75 (size of view finder, film skip to step 9) 7. Determine rendering resolution. 72dpi (not needed for film since film is scanned) 8. Calculate rendering pixels dimensions. 8.75*72=630 pixels & 5.25*72=378 pixels 9. Determine image safe width. 7 -.25 =6.75 10. Calculate image safe to render width ratio. 6.75/8.75=.77143 11. Calculate image safe to render height ratio 4.75/5.25=.904762 12. Calculate parallax to render width ratio. .75/8.75=.085714 13. Create 3D scene or set . Lightwave, Strata, Softimage etc. 14. Select the center of your scene. for example (0,0,0) 15. Place your camera on the z axis (0,0,z) follow center frame cropping (center of track) 16. Cropping Center frame cropping percentages are used since your view may not be actual size. Using a combination of the z axis value and the camera's focal length, position the camera so that the objects in the scene are within the center 77.143% of the render width and the center 90.4762% of the render height. This will ensure that all of the objects are within the image safe of the final image. Objects or portions of objects that are on or in front of the z=0 plane should not have any edges that extend beyond the image safe. The closer the object is towards the camera the farther it should be from the edges of the image safe. Saving a copy of the scene will assist in making corrections during the next step. 17 Parallax motion and cropping Move the camera to the left so that the aim point (0,0,0) is 4.2857% of the camera s view from the center of the camera's view. Half the value calculated in step 12. The aim point should be to the right of the center of the camera's view. Make a key frame for the camera at this location and make another key frame on the opposite side of the y axis. Be sure that your camera movement is linear, a spline path will make uneven steps between frames. Check the position of objects on or in front of the z=0 plane to ensure that they remain within an area that is 77.143% of the camera's view centered on the displaced aim point. Make any final adjustments to the object positions. Your scene is now ready to render. Typically, 30 frames should be sufficient to produce a good sequence. We can accept either Quicktime or individual pict/tiff files. Copyright (C) 1999-2010 Digillax Systems. All rights reserved. | ||
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Last update Friday, November 26, 2010 05:20:35 AM