User’s guide for

VIDAR TWAIN 7.0

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 1

VIDAR Part Number 18873-001 Rev B February 2010 © Copyright by VIDAR Systems Corporation. All rights reserved. Printed in the USA. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written permission of VIDAR Systems Corporation. Terms denoted by the trademark symbol (™ or ®) used in this publication are trademarks or service marks registered in the United States or other countries.

Note: Your system configuration may not be covered by this document. Although the TWAIN 7.0 module operates with a range of configurations, VIDAR does not support systems with specifications outside those listed in this manual.

365 Herndon Parkway Herndon, VA 20170 U.S.A.

Sales: 1-800-471-SCAN or 1-800-471-7226 Email: sales@vidar.com

Phone: 1-703-471-7070 Fax: 1-703-471-7665 Internet: www.filmdigitizer.com

Technical Support: 1-800-471-SCAN (7226) or 1-703-471-7070 E-mail: medtech@vidar.com

Authorized representative in Europe

Emergo Europe Molenstraat15 2513 BH, The Hague The Netherlands

Phone: +31 (0) 70.345.8570 Fax: +31 (0) 70.346.7299 E-mail: service@emergogroup.com

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 2

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 3

Contents Introduction......................................................................................................... 4

About this manual.................................................................................. 4 Conventions used in this manual .......................................................... 5 Skills required........................................................................................ 5 Customer support.................................................................................. 6

Contacting VIDAR ............................................................................ 6

Getting Started.................................................................................................... 7 System requirements ............................................................................ 7 Turning on the VIDAR film digitizer ....................................................... 7 Installing the VIDAR TWAIN software................................................... 8 Accessing the VIDAR TWAIN interface .............................................. 19

Main window ..................................................................................................... 20 Image Properties ................................................................................. 20

Resolution....................................................................................... 21 Depth .............................................................................................. 21 Num. Films ..................................................................................... 21

ROI Properties..................................................................................... 22 Scan Properties................................................................................... 22

Auto Contrast.................................................................................. 22 Contrast Stretching......................................................................... 23 Adaptive Histogram Equalization ................................................... 23 Edge Enhancement........................................................................ 23 Auto Eject ....................................................................................... 24

Pre Scan, Eject and Scan buttons ...................................................... 24 Cancel ................................................................................................. 24 Reset ROI............................................................................................ 24 Calibrate button ................................................................................... 24 Advanced ............................................................................................ 25 About ................................................................................................... 25 Exit …………………………………………………………………………..26

Advanced Settings window ............................................................................. 27 12 Bit Shift ........................................................................................... 27 Measurement Units ............................................................................. 27 Translation Table................................................................................. 27 Log Level............................................................................................. 28 Auto Contrast ...................................................................................... 28

Film/Holder: .................................................................................... 29 OK button ............................................................................................ 30 Cancel button ...................................................................................... 30

Scanning films .................................................................................................. 31 Overview ............................................................................................. 31 Loading a film ...................................................................................... 32

Loading a film ................................................................................. 32 Prescanning and defining a region of interest (ROI)........................... 34 Scanning ............................................................................................. 36 Ejecting a film ...................................................................................... 36 Finishing up ......................................................................................... 37 Using the image application ................................................................ 37

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 4

Introduction

About this manual This manual is for users who plan to capture x-ray images from film in digital form using a VIDAR Dental Film Digitizer and the VIDAR TWAIN software interface. The TWAIN interface must be used inside a TWAIN complaint host imaging system. The manual explains how to use VIDAR’s Dental Film Digitizer with commercially available TWAIN-compliant applications for Windows Windows™ XP and VISTA. The VIDAR TWAIN software interface version 7.0 is compatible with the VIDAR Dental Film Digitizer.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 5

Conventions used in this manual

Special keys you press on the keyboard appear in small capitals. For example, ENTER and TAB.

File and directory names appear in italic. For example,

\My Documents\Notes.txt.

Menu names and menu commands appear in Block Letters. For example, File > Open... .

Windows, buttons, dialog boxes and other on-screen features are named in Bold type.

For example, the Save button.

Hyperlinks are underlined. If you are viewing this document electronically, click a hyperlink to view related material.

Skills required You should have experience using computer applications running under Windows™ XP or Windows™ VISTA.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 6

Customer support

Note: For customer support questions, VIDAR recommends that you first contact the system integrator that supplied your system, since the integrator is more familiar with the specific system setup than VIDAR personnel.

Before calling or e-mailing VIDAR, be sure you have the following information:

Customer name and contact information, including telephone number and e-mail address

Software name and version Scanner serial number

Contacting VIDAR Technical support for film digitizers is available from VIDAR Monday through Friday from 8:00 am to 12:00 pm, and 1:00 pm to 5:00 pm Eastern Time.

By e-mail: medtech@vidar.com.

By telephone: call 800-471-7226 (in the U.S. only) or 703-471-7070 and ask for Medtech.

Technical and sales information is also available on the web at www.vidar.com.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 7

Getting Started

For instructions on setting up and using your VIDAR Dental Film Digitizer, please refer to the Installation and User guides supplied with the product.

System requirements

You must supply a computer system that meets or exceeds the following requirements: 3.0 GHz Pentium 4 PC 512 MB of memory 30 GB Hard Disk USB 2.0 connectivity

Note: Scanning films at high resolution and bit depth produces very large files, which must fit into system memory. If installed memory is not sufficient, software and/or system crashes may occur.

Windows XP professional Edition (Service Pack 3) or Windows VISTA Business

Service Pack 1 15” display with 1280 x 1024 resolution. Display card with 16 MB of video RAM CD-ROM drive TWAIN-compliant host application.

Turning on the VIDAR film digitizer Always turn on the VIDAR film digitizer before turning on the computer (this allows the computer to recognize the film digitizer). Refer to the hardware manual for the location of the film digitizer’s power switch.

Installing the VIDAR TWAIN software

Note: you must install VIDAR’s STI drivers before using TWAIN. Please see the VIDAR Dental Film Digitizer Installation Guide for more details.

You may obtain the TWAIN 7.0 from thte TWAIN 7.0 Installation CD, VIDAR’s technical support (medtech@vidar.com) or via VIDAR’s web page, www.vidar.com/. Please note that the TWAIN-compliant host application must be intalled before installing the TWAIN.

To install the TWAIN: If using a TWAIN 7.0 Installation CD, browse to the Setup.exe file on the CD. If acquiring TWAIN from VIDAR’s web site follow the instruction from the website.

1. Double-click on setup.exe

2. A Wizard will launch to guide you through the installation process (This part of the process will ensure the environment is prepared on your PC.) Any of the processes that have to be installed will be listed below. This list consist of all of the processes requrired. If these processes are already installed on your PC you will not see them.

3. Follow the instructions for the Pending items listed on your set up screen. The sceens to follow will include all Pending items listed above. If you do not see these items please continue onto the next applicable screen(s).

4. If the .net Framework is required Select I have read and Accept the terms of the

License agreement and Select Install. 18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 8

5. There will be several screen shots during this process.

6. At the end of you’re the installation the sceen shot below will appear. Select Exit.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 9

7. At the completion of the .net Framework you will be asked to reboot your PC

Select Yes Reboot now. Once the PC reboots it will bring you back to the installation screen to continue with the installation of TWAIN 7.0.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 10

8. Next you may be asked to installed Visual C++ 9.0 Runtime Libraries. Select

Install and when prompted select Next to continue or go to the Matlab installation screens.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 11

9. Check the I have read and accept the license terms and then select Install.

10. Once the installation has completed Select Finish to complete the installation of the Visual C++ Software.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 12

11. The final Step will be the MATLAB Installation

12. Select the proper Language from the pull down menu and Select OK

13. The TWAIN requires you to install the Matlab Image Processing Library. Click Install.

14. You may need to install other components on your PC in order to run Matlabs. The wizard will direct you. Click Install to install these components.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 13

15. Click Next to begin the Matlabs install.

16. Edit User Name and Organization if desired and click Next to continue the

installation.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 14

17. Change the installation folder if desired. Otherwise click Next to continue the

installation.

18. Click Install to being installation of MatLabs.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 15

19. When the installation is complete,click Finish.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 16

20. Now you will begin the installation of the VIDAR TWAIN. Click Next to begin.

21. Select I accept the terms of the license terms to accept the License Agreement.

Then click Next.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 17

22. Click Install to begin the installation of the VIDAR TWAIN.

23. Click Finish when you see the Intsallation complete message.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 18

Accessing the VIDAR TWAIN interface Many dental applications use TWAIN software to enable communications between their application and the film digitizer.

To access the TWAIN interface:

1. Turn the film digitizer on and ensure that it has completed its warm-up process (the film digitizer’s LED should be lit with a constant green light). The warm-up time for the Dental Film Digitizer takes a little over 5 minutes.

2. Apply power to the PC

3. Launch the host application.

4. In the host application, select the VIDAR TWAIN interface. Note: In most TWAIN-compliant host applications, you must

select the appropriate TWAIN interface before you can import from a peripheral device. If you have just one TWAIN interface installed, you only need to select it once—before its first use. If you have multiple TWAIN interfaces, you must select the desired TWAIN each time you need to change between interfaces).

5. Use the host application’s import or acquire function to access the TWAIN

scanning interface. The method for doing this depends on the host application (refer to the host application software manual for instructions on selecting and importing/acquiring TWAIN scanning interfaces).

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 19

Main window

After setting up the VIDAR film digitizer, connecting it to your computer, and installing the TWAIN software, you may begin digitizing films. This chapter explains each of the controls in the Main window. Options in the Main window (shown below) of the VIDAR TWAIN software control the film digitizer’s basic scan parameters.

This space is the Preview area, where images will appear when a Pre Scan is performed. When the Scan command is used, images will appear in the host application.

Image Properties

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 20

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 21

Resolution Resolution determines the amount of detail captured in the film. Scanning at a higher resolution captures finer detail than scanning at a lower resolution. However, a lower resolution image has a smaller file size and requires less memory. Select a resolution value based on the display capabilities of your computer monitor, the amount of available disk storage space, the transmission time requirements, and the need for fine detail. The default of the device is set to 300 dpi as this delivers optimal detail for a medical imaging application. The Resolution list allows you to select one of the resolutions supported by the film digitizer. The list shows resolutions in dots per inch (dpi). The resolutions available for the Dental Film Digitizer are 75,150 and 300 dpi

To set resolution: Open the Resolution list and click the desired resolution.

Depth Depth refers to the number of data bits the film digitizer captures per pixel. It determines the maximum number of grayscale levels the film digitizer can distinguish in an image. Use the Depth list to select the number of data bits saved for each pixel in a scan. The depths available for the Dental Film Digitizer are 8, 12, and 16. Not all host imaging applications will support all image depths. Most applications do support 8 bit image depth. This ability to select 12 and 16 bit may be disabled in your system if the host application communicates with the TWAIN that these resolutions are not supported. (Please note that not all devices provide this type of communication, if errors occur in 12 bit mode you may need to select the 12 Bit Shift check box in the Advanced Settings window. If errors persist in 12 or 16 bit mode, your host application may not support these bit depths, and you should adjust this setting back to 8 bit depth. The most popular supported TWAIN transfer mechanism is a Native transfer. This method only supports an 8 bit transfer. So if you desire to scan in 12 or 16 bit mode with TWAIN you will need to change the transfer mechanism in the host software (not always available) to File or Buffered or change host applications to a software that supports a File or Buffered Memory transfer mode. Further note that the internal image properties autocontrast and edge enhancement described in the next section can only be supported in Native or File transfer modes. For most applications an 8 bit file with access to the image properties autocontrast and edge enhancement is the desirable solution).

To set depth: If options are available, open the Depth list and click the desired depth. Num. Films The Dental Film Digitizer does not support multi-sheet film feeding. This setting is therefore set statically at 1 when connected to this device.

ROI Properties

ROI Properties shows the location a region of interest once one is selected. Until then this section will be blank. The Units menu (in the Advanced Settings Window) determines the unit of measure (inches or centimeters) for the ROI Properties.

Scan Properties

Auto Contrast VIDAR’s TWAIN features two different automatic image contrast algorithms. Contrast Stretching and Adaptive Histogram Equalization. These can be used independently of or in conjunction with one another. They can only be used with applications supporting the TWAIN Native or File transfer mechanism. Therefore if the application informs the VIDAR TWAIN in advance of a desired Buffered Memory transfer, these items may be grayed out.

Some applications automatically apply image enhancement such as Contrast Stretching, Histogram Equalization and/or Edge Enhancement when an image comes into the application. Therefore desired use of these functions may be host application software dependant. In general if the resulting image from the TWAIN appears light and over exposed, application of contrast stretching can make the image much more appealing.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 22

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 23

Please note that there are Advanced Settings that affect the application of both of these image enhancements. See the next chapter “Advanced Settings window” for more details which can allow you to easily generate the best image quality Contrast Stretching Contrast stretching is a simple image enhancement technique that improves the contrast in an image by stretching the range of values it contains to span the full range of pixel values allowed. This generally improves the appearance of the image. This should only be used if the host application is not applying an image enhancement function. You should initially try images with this setting on and off in your application to see which one gives a better overall appearance. The default setting in the TWAIN is to have Contrast Stretching enabled. As with other settings, once you make changes, they are saved.

To set Contrast Stretching: Click on the check box to the right Contrast Stretching until a check mark appears.

Adaptive Histogram Equalization Histogram Equalization is a method in image processing of contrast adjustment using the image's histogram. This method usually increases the global contrast of many images, especially when the usable data of the image is represented by close contrast values. Through this adjustment, the intensities can be better distributed on the histogram. This allows for areas of lower local contrast to gain a higher contrast without affecting the global contrast. Histogram equalization accomplishes this by effectively spreading out the most frequent intensity values. Adaptive Histogram Equalization differs from ordinary histogram equalization in the respect that the adaptive method computes several histograms, each corresponding to a distinct section of the image, and uses them to redistribute the lightness values of the image. This can be very useful when digitizing a set of bitewing films in which the individual histograms can more appropriately act on each individual image in the set – each with it’s own relative properties.

To set Adaptive Histogram Equalization: Click on the check box to the right

Adaptive Histogram Equalization until a check mark appears. It is possible to combine both of these functions for a more aggressive image processing. Edge Enhancement Edge enhancement is an image processing filter that enhances the edge contrast of an image to improve its apparent sharpness. The filter works by identifying sharp edge boundaries in the image, such as the edge between a subject and a background of a contrasting color, and increasing the image contrast in the area immediately around the edge. This has the effect of creating subtle bright and dark highlights on either side of any edges in the image, leading the edge to look more defined when viewed from a typical viewing distance. VIDAR’s TWAIN allows you to set various levels of Edge

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 24

Enhancement, or to turn this feature off entirely. By default this enhancement is set to Medium.

To set Edge Enhancement: Click on the Edge Enhancement control box and select None, Low Medium or High.

Auto Eject The Auto Eject option controls what happens to films that have been scanned.

To eject each film after each scan: Activate Auto Eject. The film digitizer will be ready to accept another film when a scan is complete. Auto ejection is useful when you are scanning many films consecutively.

To retain the film in the digitizer after each scan: Deactivate Auto Eject. The film

will stop moving when the scan is complete or at the end of the film (whichever comes first) at which point the film will be backed up to the stage position for scanning again. This is useful when you want to perform multiple scans on one film. For example if you are using Pre Scan to scan regions of interest (a single bitewing film held in a film mount) turning off the auto eject and using the Pre Scan function can be very helpful. Unfortunately some applications automatically close the TWAIN application after each transfer, so not all applications will support consecutive scanning of multiple Regions of Interest.

Pre Scan, Eject and Scan buttons

The Pre Scan, Scan and Eject buttons are described in the “Scanning films” chapter, later in this manual.

Cancel The Cancel button will cancel either a Scan or a Pre scan action – film movement after this action will depend on the setting selected in Auto eject.

Reset ROI The Reset ROI button will remove the selected Region of Interest selected after a Pre Scan. Alternatively the user can simply draw another ROI.

Calibrate button Calibrate directs the film digitizer to calibrate white and black levels. Calibration compensates for pixel-to-pixel variations in both the white and black ends of the grayscale to produce an even, consistent scan. Calibration is also automatically performed when the film digitizer is turned on. Additionally the VIDAR Dental Film Digitizer automatically calibrates itself whenever not being user (and powered on). However if you are not getting the image quality you feel appropriate, forcing a manual recalibration is a good first step. This calibration will take a little over 5 minutes.

To begin calibration: Click Calibrate. The status bar at the bottom of the TWAIN will display a message during calibration as well as when calibration has completed in a little over 5 minutes.

Advanced

There are items considered more advanced settings that can control Main window setup and include film digitizer controls that are not in the Main window. The “Advanced Settings window” chapter, next in this manual, provides details. To access the Advanced Settings window: In the Main window, click the Advanced

button.

About The About window displays version and copyright information about the TWAIN software as well as the digitizer connected and connectivity software.

To view the VIDAR TWAIN version: In the Main window, click the About button. Clicking Copy to Clipboard will copy this information so that it can be pasted to another application such as email in the event that technical support is needed. Clicking OK will close this window.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 25

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 26

Exit

To close the TWAIN interface without performing a scan: In the Main window, click

Exit.

To cancel the current scan or prescan: In the Main window, click Cancel. Control returns to the main (host) application.

Advanced Settings window

To access the Advanced Settings window: In the Main window, click the Advanced button.

Measurement Units

The Units list controls the unit of measure for the ROI Properties section in the Main window. If you change the unit of measure in the Units list, these settings change accordingly.

To select a unit of measure: Open the Units list and click Inches or Centimeters.

Translation Table The Dental Film Digitizer is a medical device and therefore has only 1 available translation table or data output curve, the LOG table. Please contact Medtech@vidar.com if your device is reporting any other translation tables as his indicates that your device does not have the appropriate settings for this application.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 27

Default Transfer Method For host applications that do not “communicate” with VIDAR’s TWAIN to negotiate for a transfer method, VIDAR will default to a Native transfer protocol. However, the user can change that default method.

To change default transfer method: Open the list and click the transfer method you desire.

12 Bit Shift

12 Bit Shift converts 12-bit data to16-bit data before the data is transferred to the host application. This allows you to perform a 12-bit scan transfer is some applications that do not natively support 12 bits. You will need to test the usefulness of this toggle in your specific software.

Note: Only activate the 12 Bit Shift option if the host application supports 16-bit data.

To use 12 bit shift: Activate 12 Bit Shift by clicking on the checkbox. Log Level

The Log level controls the amount of information which is captured in a log file. This is useful in the event that troubleshooting is needed.

To change log level: Open the list and click the level you desire. You should normally change this setting if instructed by technical support.

Auto Contrast The Auto Contrast area will affect the application of image processing selected on the main UI.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 28

Advanced Options window 29

Film/Holder: Presets for this area have been set based on favored settings for specific film types.

General: is a basic setting to be used as a default (gives a good appearance across a wide variety of films) Holder # XX-XXXX: refers to a specific Dentsply Rinn Film Holder supported by the VIDAR film digitizer. The amount of clear or black space on the holders which are not image specific will have an effect on the image processing routines. When you select the specific holder being scanned, these spikes in the data can be disregarded so that the image processing is relevant only to the image data and not the holder Panoramic: applies settings most appropriate to a variety of panoramic films Custom: allows you to create your own profile to match your films/preferred holders

To select a specific film or holder type: Open the list and click the film/holder type you desire and click OK to exit the Advanced Settings window with this selection.

Low Cutoff/High Cutoff %

These settings will be applied only if Contrast Stretching is selected on the Main window. These low and high cutoff amounts allow you to compensate for spikes in data at the low and high end which are not relevant for image processing, such as black or clear film holders. Low refers to the darkest data in the image and High to the lightest. For example, Holder #21-6200 contains a large amount of black data. So 37% of the low-end data is disregarded in the image processing.

Tile Columns/Tile Rows

These settings will be applied only if Adaptive Histogram Equalization is selected on the Main window. Tiles refer to regions in the image. This causes the Histogram Equalization to be performed on the number of tiles or regions, rather than the entire image. The neighboring tiles are then combined using bilinear interpolation to eliminate artificially induced boundaries. The contrast, especially in homogeneous areas, can be limited to avoid amplifying any noise that might be present in the image. Higher numbers of tiles will create a more aggressive image processing. For example, Holder #21-6200 is wide across the x axis and thinner along the y. So it’s column/row preferred settings are 13 and 5. As this holder contains 20 individual images in total, we wish to create more regions. Compare this to a panoramic setting. There are only general variances in the image as it represents 1 single scan. In this case, a setting of 4-3 is recommended. You cannot change the default settings of the film types, but there is a customer selection that you can create and change.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 29

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 30

To adjust the custom settings: Open the list and select Custom. Edit the Low

Cutoff % and High Cutoff % settings as well as Tile Columns and Tile Rows to your desired settings. Click OK to exit the Advanced Settings window and save the new settings and selection of custom.

OK button

To accept changes and close the Advanced Settings window: Click OK. Control

returns to the Main window.

Cancel button

To close the Advanced Settings window without saving changes: Click Cancel. Control returns to the Main window.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 31

Scanning films

Overview Here are the major steps required to scan one or more films (with references to sections later in this chapter): 1. Load a single film into digitizer’s feed tray. See “Loading films,” 2. (Optional) Prescan film, then (optional) define a region of interest (ROI). See “Prescanning and defining a region of interest (ROI).” 3. Scan film See “Scanning,” which covers scanning films 4. (If film is not automatically ejected...) Manually eject film. See “Ejecting a film.” 5. Accept or discard image. See “Finishing up.”

Loading a film Loading a film Small films such as bite-wings must be loaded into a non paper-based x-ray film mount for digitizing. The Dental Film Digitizer ships with 5 such mounts which meet the digitizer’s film size specifications.

CAUTION: If a film or mount not meeting the film digitizer’s specifications is placed into the digitizer, the films or mounts can become lost in the digitizer causing as repair need not covered under warranty. Paper based or cardboard mounts should not be used as bits of paper can drop off into the optics of the film digitizer causing image quality issues necessitating non-warranty repair.

Larger films such as panoramics and cephalometric films can be loaded directly into the digitizer. Place the film or carrier into the digitizer right justified (close to the triangle on the

entrance tray) as shown here:

Triangle exaggerated in picture for easy identification of location

Film

When the Dental Film Digitizer detects the film/carrier, it stages the film/carrier—

pulls it in about 1" (2.5cm), then pushes it back out about 1/2" (1.25cm). This may take a few seconds.

CAUTION: If the film or carrier is not staged properly, it is recommended to use the scanning application’s “eject” command to remove the film. Gently pulling the film out of the digitizer will not harm the digitizer, but could potentially result in damage to the film.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 32

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 33

Note: When a film/carrier has been staged, it is in the digitizer’s light path. The ADC (Automatic Digitizer Calibration) feature requires that the light path be clear of the film/carrier for proper background calibration of the digitizer. The digitizer will automatically adjust the film or carrier’s position to properly proceed with ADC. Depending on the location of the film or carrier’s leading or trailing edge, and the length of time it has been blocking the light path, and then it will be: a) pushed up, b) pushed down, or c) ejected to remove it from the light path.

Prescanning and defining a region of interest (ROI) Pre scanning digitizes the entire film at the lowest resolution and displays the image in the Preview area of the Main window. A pre scan makes it easier to define a region of interest (ROI) or smaller section of the entire film holder or xray which you would like to collect as a single image. If auto eject after scan is checked then the film automatically restages after a pre scan in preparation for a scan. Pre Scan automatically sizes the original film and allows you to use the image preview to define the region of interest. Please note that some applications force the TWAIN to close after each scan. In this case, the pre scan will not be a usable function.

To perform a pre scan:

1. Load the film into the film digitizer (as described in “Loading films,” earlier in this chapter).

2. If you wish to scan multiple Regions of Interest on the same film or film carrier

AND your host application does not force the TWAIN to close after each image transfer, then un-checking auto eject on will allow you to select successive Regions and then scan based on the same pre scanned image.

2. In the VIDAR TWAIN interface Main window, click Pre Scan.

To cancel the pre scan before it is complete: Click Cancel. The film moves through the film digitizer. After the preview scan is completed, a

thumbnail of the image appears in the Preview area of the Main window. The film will move back up into the ready position if auto-eject is set to off.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 34

Region of interest

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 35

3. Adjust the ROI to the area you want to scan: right-drag the mouse over the desired area.

As you drag, the coordinates of the ROI are displayed to the left of the Preview

area.

To redraw the ROI: Reposition the mouse and drag again.

You are now ready to scan the ROI: when you click the Scan button (as described in “Scanning,” the next section in this chapter), only the region of interest will be scanned using the selected scanning parameters.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 36

Scanning After loading the film and specifying scanning parameters, you are ready to scan. The Scan command directs the film digitizer to scan the film loaded in the film digitizer.

To initiate a scan: First ensure the film is staged The film is staged before scanning takes place. This means that the film will be fed

down about 1.5" into the digitizer, then come back up about 0.5". In the VIDAR TWAIN interface Main window, click Scan.

Note: If no film is loaded when you click Scan, an error may be generated by the host application.

To stop a scan before it is completed: Click Cancel.

Note: The image quality received can be effected by many elements including, but not limited to, the resolution, bit depth, selection of processing features in TWAIN (contrast stretching,adaptive histogram equalization, edge enhancement, and advanced settings screen settings), a black or white intraoral film holder(which affects which settings should be used), as well as the availability of or automatic application of filters or enhancements in the host imaging software. VIDAR may have a guide available which can give guidance on the best way to set up the TWAIN when used with a variety of films in your specific host imaging application. Please contact your VIDAR reseller for advice on receiving the best image quality from your VIDAR digitizer when used with your imaging application and for your specific needs.

Ejecting a film

Ejecting causes the feed rollers in the film digitizer to turn until the film is free of the rollers and drops into the exit tray.

CAUTION: If a film is held in the film digitizer by the feed rollers, pulling it down and out slowly will not harm the digitizer, but may scratch the film; however, it’s best to use the TWAIN interface to eject the film, as described below.

Note:

If Auto Eject is activated films are ejected automatically. If a film is not automatically ejected (Auto Eject is off), then after the scan is complete:

To eject the film from the feed path: Click Eject.

Finishing up After the film digitizer captures the image, the image will either appear in the host software application, or the image will be saved to the specified location (File Mode transfers). If the image was saved to file, some applications will not automatically open the images for viewing. You will need to open the file to view the image.

To close the TWAIN interface: Click Exit.

Note: If you defined an ROI, the ROI image will appear in a

separate window behind the TWAIN window. Some applications may automatically close the TWAIN application after each transfer. In this case you will only be able to select 1 Region of Interest per Preview scan. However some applications will leave the TWAIN active in which case you can select another ROI from the same preview scan and hit scan again (assuming auto-eject is off).

Using the image application

For details on zooming, panning and other image controls, refer to the manual for the host application.

18873-001 Rev. B VIDAR TWAIN 7.0 User’s Guide 37