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Frequently Asked Questions Object VR Projects Is Object VR appropriate for the objects in my collection? Is an Object VR movie project feasible for my institution? What equipment and materials are needed for this kind of Project? Image Capture How many total images are required to make an Object VR movie file? Can we include special shots to show interesting details? Can we provide for zoom or close-ups? What lighting works best? How much light is recommended? Does the size of the object matter? Is smaller better? What color background works best for image capture? Should the background be created in the studio or in later editing? Is landscape or portrait orientation recommended? Does it depend on the size of the object? Where should the camera be positioned and at what height? How can we include a scale in our Object VR movie? Image Processing How are sequential digital surrogates “stitched” together? How much cropping is required? How well does VR ObjectWorx work? Is it easy-to-learn? Does the use of close-ups increase the amount of time to process the Object VR images? Will the color be different from the actual object? Image Presentation Which viewer is needed to play my Object VR movie? How much importance should be given to download time? How much resolution is satisfactory for final presentation on the Web?
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Is Object VR appropriate for the objects in my collection? Object VR movies provide an interactive, 3-D digital viewing experience allowing users to more fully explore objects from your institution’s collections. Two-dimension digital images often provide sufficient visual representation of three dimensional objects and artifacts. However, multi-faceted objects (with interesting front, back, side, top or bottom views) benefit from 3-D representation, which allows viewing from several angles. Items from your collections that are used in teaching applications are often ideal candidates for Object VR movies that are then available for students via Intranet or Internet presentations. Creating Object VR movies of frequently viewed or handled objects can reduce wear and tear on the items and reduce the risk of damage to them. Fragile items can be made accessible to new users. Object VR movies can provide access not only to multiple users simultaneously but also to users across geographic and time barriers. Although the setup and photographing of digital images for Object VR movies is easier with small- to medium-sized objects, it is possible to capture images of large-size objects. (Some manufacturers specialize in turntables large enough to accommodate automobiles.) Is an Object VR movie project feasible for my institution? Like any digital project, Object VR projects require some outlay of resources in terms of both staff time and equipment. However, these projects can be completed by most institutions, even when only a modest budget is available. There are lower-cost alternatives to equipment requirements (e.g., a manual turntable instead of a motorized one). A sampling of objects may be included instead of an entire collection. Object VR movies can be completed without extensive editing of the individual images that make up the final interactive movie. Greater resources allow you to include more objects, spend more time editing, and utilize more elaborate studio equipment, thus resulting in a more polished final product. Depending upon your institution’s goals, a more polished final product may not be more important than simply providing enhanced access to your unique resources. What equipment and materials are needed for this kind of Project? Computer
Lighting
Turntable
Museum (“Sticky”) Wax Back to Top How many total images are required to make an Object VR movie file? A single rotational view of an object requires images to be captured at evenly spaced intervals all around the object (360 degrees). Fewer images taken during the rotation (e.g., images taken every 20 or 30 degrees of rotation) result in a less fluid interactive movie since there are less images available to construct the final movie. More images (e.g., images taken every 5 or 10 degrees of rotation) result in a more fluid final product. A total of 36 images are needed for 10 degrees of rotation; a total of 72 images are needed for 5 degrees of rotation. As a rule, 36 images (one taken every 10 degrees of rotation) will provide a sufficiently fluid interactive Object VR movie. A top-to-bottom view of an object may include up to 648 images – 18 sets of rotational views taken at 10 degree increments from top to bottom.) If you are working under budget or time constraints, or if your object does not have much detail, a movie consisting of 24 images (taken at 15 degree intervals) or 18 images (taken at 20 degree intervals) may be acceptable for your intended users. Can we include special shots to show interesting details? Can we provide for zoom or close-ups? You can include special close-up shots highlighting interesting details of your objects, though these may be separate from the Object VR movie itself. QuickTime files (*.mov), made using software such as VR ObjectWorx or QuickTime VR Authoring Studio, include a zoom option for users viewing the movie. Zoom works best with higher resolution images. However, higher resolution movies have much larger file sizes and thus take longer to download on users’ computers. Consider providing users with both high resolution versions (e.g., 300 dpi) and standard resolution versions (72 dpi) of Object VR movies of items with interesting details or facets. QuickTime also allows adding effects, such as hyperlinks, within the Object VR movie. These hyperlinks could lead users to other images of your object showing visual details or interior features. Also consider including additional images of your object as part of your final Internet or Intranet presentation. Use thumbnail images to link to more detailed or close-up views, to show top or bottom details, or to provide size comparisons. Can we show how telescopic devices are expanded and closed? Are there other “animated” applications appropriate for a specific object or collection of objects? Object VR movies are a great way to demonstrate how a telescopic object works. Instead of rotating an object, carefully expand the object evenly and take a photo at each intermediate position. There is no standard number of images necessary – the more intermediate images included, the smoother the final interactive movie. In order for the movie to be continuous, you must show the object closing as well. Either photograph the telescopic object closing (with an equal number of intermediate steps) or, more simply, make copies of the sequence of images showing the object expanding. Then insert those images in reverse order into your sequence of images for the finished movie. Though Object VR movies have been used most often to show rotational views of static objects, there is no reason they could not be used to demonstrate other “animated” actions, such as panels opening and closing. Just remember that you are creating a continuous movie, so the end of the action (e.g., rotation or telescoping) must seamlessly blend into the beginning of the action. What lighting works best? How much light is recommended? The goal of your lighting setup is to provide sufficient light to showcase your objects, allow detail to be visible, minimize shadows, provide a consistent light level for all the images in a single Object VR movie, and contrast the objects from the background. A very good, and relatively inexpensive option is to use tungsten lamps (available at local photography supply stores). On most cameras there is a setting for tungsten lights. This creates a true color. Halogen lamps also work well and are easy to find. If possible, use photography umbrellas to reflect and diffuse light onto your objects. Using the digital camera’s flash bulb is not recommended. Light from a single source will cast shadows. Light levels will most likely vary from image to image, creating a “jerky” appearance to the final interactive movie. Does the size of the object matter? Is smaller better? As long as an object or artifact fits on the turntable or pedestal, can be anchored securely, and can be rotated without changing position, the size of the object does not matter. Smaller is not always better because small objects often do not have the same kind of detail that larger, more ornate objects have. Your camera tripod and lights may need to be moved (forward or backward, higher or lower) in order to accommodate capturing images of different sized items. What color background works best for image capture? A uniform background that clearly sets off your object is best. A black background can be easily created in your studio and is very commonly used in Object VR movies. However, it may not provide the best showcase for your objects. The final movies will appear dark and details of your object may not be clearly visible. Unless your object is very light in color, a light-colored or white background is recommended. A uniform white background is difficult to achieve in the studio as it will require additional lighting equipment. An alternative way to realize a uniform white or light-colored background is to use Photoshop or other image editing software to replace the background from each captured image with the background color of your choice. If you choose to edit out the turntable and/or pedestal, you can create Object VR movies that make your object appear to be floating in space. Should the background be created in the studio or in later editing? That depends on your time and resources. It is quicker to create the background in the studio using a backdrop than it is to edit each image individually in Photoshop or other image editing software. However, a uniform background that sets off your objects is difficult to achieve in the studio. How are shadows handled? Positioning the lighting correctly can eliminate most, if not all, shadows. Placing the lights equidistant to the object and at about a 45 degree angle will help reduce shadows. Once the images have been captured, it is easy to remove shadows using Photoshop or other image editing software. Is landscape or portrait orientation recommended? Does it depend on the size of the object? The size and shape of your object will determine whether portrait or landscape orientation is more appropriate. Since computer monitors are wider than they are tall, landscape orientation allows the largest possible size for the finished Object VR movie. Where should the camera be positioned and at what height? The camera should be level with the object and far enough away so that you can see the entire object at all angles of rotation. If the top or bottom of the object contains interesting aspects that you wish to highlight, consider placing the object on its side on the pedestal. You can then rotate the images in Photoshop and create an Object VR movie that shows the rotational spin as top to bottom rather than side to side. Another option is to place the camera slightly higher than the object in order to show the details on its top. However, this option may distort the size and shape of the object in your finished movies. How can we include a scale in our Object VR movie? The most professional way to include a scale (ruler) in your interactive movie is to insert one into each image (frame) of the movie during the editing phase (Photoshop). First photograph a scale at the same magnification as the object – the easiest way is to take an additional digital photograph of the object on the pedestal with a scale next to it. In Photoshop, open this additional image and copy the scale from the image (for example, using the Rectangular Marquee Tool). The scale can then be pasted into each of the images that will be “stitched together” to make the interactive movie. You must be careful to place the scale in the same location in each of the images (use Photoshop’s rulers and guides and “snap-to” functions to insure consistent placement). A simpler option is to include a common object (such as a quarter) next to or in front of the object on the turntable or pedestal. You will need an adherent (such as museum wax) to anchor the quarter on its edge and keep it steady during the turntable rotation and image capture process. Motion control software, such as eMCee, allows for automation of the image capture process (e.g., coordination of the camera and turntable). How much automation is best? The turntable rotation and image capture process can be fully automated using motion control software, such as eMCee. The precise rotation of the turntable, timed intervals between rotations, and camera shutter release can be programmed, creating a fully automated process. However, the motorized turntable and motion control software must be compatible with the camera in order to fully automate the image capture process. Be sure to check the software specifications for a list of compatible digital cameras. Some photographers may wish to have more control over the image capture process. A manual turntable with click-stops at every 10 degrees may provide sufficiently precise rotation. Manual rotation allows the photographer time to make sure that the object is steady and unwavering before an image is captured. Back to Top What is the quality of the resulting Object VR file at various resolutions? How do we balance file size with image quality? The standard resolution for Web presentation of images is 72 dpi. For many Object VR projects, this resolution standard provides a sufficiently detailed view of the objects and will provide some zoom capability for users. Object VR movies consist of a number of images (usually 36), so the file size of a movie is significantly larger than that of a single image and will take much longer to download. If the image resolution is greater than 72 dpi, the resulting file becomes larger still and will further increase download time for users (even those with high speed connections). Higher resolutions (e.g., 150 dpi or 300 dpi) will allow for more clarity when using the zoom function. If you feel this is important for your users, consider providing both low (72 dpi) and high (150 dpi) resolution versions of your Object VR movies. If download time is not a consideration (for example, the interactive movies are to be used over an Intranet system or only by users with T1 connections) higher resolution and larger file sizes may be acceptable. How are sequential digital surrogates “stitched” together? The images are stitched together using movie authoring software such as VR ObjectWorx, QuickTime VR Authoring Studio, or Widgetizer. The sequential series of JPEG images, showing a complete rotation of an object, are loaded into the software. The software creates an interactive movie (in QuickTime format, for example) which is viewable by users using a compatible viewer (e.g., QuickTime) on their computer. How much cropping is required? Cropping can be done at your discretion. You may wish to eliminate excess background by cropping your images in Photoshop or other image editing program before creating your final Object VR movie. Cropping can be done using the automated Action function in Photoshop. How well does VR ObjectWorx work? Is it easy-to-learn? VR ObjectWorx is an easy-to-use movie authoring software program. The software leads the user through the appropriate series of steps to create interactive QuickTime Object VR movies. Does the use of close-ups increase the amount of time to process the Object VR images? The placement of the camera or zoom is irrelevant to the editing of the images. The amount of time spent editing is based on how much needs to be changed on each individual image (e.g., changing the background, cropping, rotating, changing color levels, etc.). Whatever changes you make to one image in your sequence of rotational images need to be made to all the images in your sequence. Many image editing changes can be done using automated action functions in your image editing software program. Will the color be different from the actual object? Lighting and your camera’s settings will affect the accurate representation of color. Check your digital camera’s manual for instructions on how to properly set up your camera’s light settings (for example, set your camera to “tungsten” if you are using tungsten lamps). Look at your object through the camera’s LCD monitor to make sure the colors are the same as you see through your eyes. Back to Top Which viewer is needed to play my Object VR movie? The format of your Object VR movie will determine which viewer is required for your users. QuickTime files (*.mov) require users to download Apple’s QuickTime viewer. This plugin can be downloaded for free and is compatible with both PCs and Macs. Other movie files (e.g., *.avi or *.wmv) may require different viewers (e.g., Windows Media Player), which are also downloadable for free. Learn about the software being used for creating your interactive movies and download the appropriate viewer. Make sure to inform your users which viewer is required and provide hyperlinks for downloading the plugin. How much importance should be given to download time? Download time may be very important to users. Many people will not want to wait longer than a minute for a movie to load. Consider providing more than one size file for your users to download, giving them the option of choosing the smaller or larger files. How much resolution is satisfactory for final presentation on the Web? The standard for web presentation of images is 72 dpi. Higher resolutions may provide greater detail, but will result in larger files that will take longer to download. When deciding on resolution, consider your users and their probable connection speed, the delivery method for the movies (Intranet or Internet), and the ultimate purpose of your movies (instructional aspects, zoom capability, etc.). Back to Top |
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