- Email: [email protected]
Simplifying the correction of the digital image in shade communication
Simplifying the correction of the digital image in shade communication Lambert J. Stumpel III, DDSa San Francisco, Calif
Photography may be an important tool in the communication between dentists and dental technicians; more so when these team members are not in the same location. Traditionally, the information carrier has been analog film.1,2 Increasingly, however, digital media are employed.3-6 The exposure variables are relatively similar for both analog and digital photography. The digital image has the advantage of immediate verification, so the intended exposure and framing can be evaluated. The darkroom process in the analog workflow has provided some control over the end product. Computer software is the digital darkroom. It allows quantification and controlled modification of a digital image. By analyzing an image, the software measures the quantity of all of the colors in an image. A histogram illustrates how pixels in an image are distributed by graphically illustrating the number of pixels at each color intensity level. The histogram indicates if the image has enough detail in the shadows, mid tones, and highlights. Pure black is situated on the left and pure white on the right side of the histogram. Shade communication is highly dependent on a true
image. It is imperative that the monitors used to view the image are color calibrated (Optical ColorVison; Pantone Inc, Carlstadt, NJ). Every computer monitor has a native colorcast; calibration ensures that this cast is corrected so the displayed image is true. This article describes a simple method to standardize a digital image used for shade communication with the dental laboratory.
PROCEDURE 1. Cut a 5-mm piece of 12-mm-wide black/white labeler tape (TC-20; Brother International Corp, Bridgewater, NJ). Remove the protective backing. 2. Wrap the tape, which functions as the white point for computer correction, around the metal holder just under the ‘‘ceramic’’ tooth portion of a shade guide tab (Lumin Vacum; VIDENT-CA, Brea, Calif). 3. Make photographs with the shade guide positioned parallel to the reference teeth. (s2Pro; Fuji Film Co, Ltd, Tokyo, Japan)
Fig. 1. Original image with corresponding histogram.
a
Private practice San Francisco, Calif; Director, Implant Prosthetics, Surgical Implant Training, Highland Hospital, Oral & Maxillofacial Residency Program, University of the Pacific, San Francisco, Calif; Assistant Clinical Professor, University of California San Francisco, School of Dentistry, Department of Restorative Dentistry, San Francisco, Calif. J Prosthet Dent 2004;92:202-3.
202 THE JOURNAL OF PROSTHETIC DENTISTRY
4. Open the images in the image processing software (Photoshop CS; Adobe Inc, San Jose, Calif). 5. On the toolbar select: ‘‘Image,’’ followed by ‘‘Adjustment,’’ followed by ‘‘Levels.’’ This will bring up the ‘‘Levels’’ box with the histogram. Ensure that the preview box is checked. Select the VOLUME 92 NUMBER 2
STUMPEL
THE JOURNAL OF PROSTHETIC DENTISTRY
Fig. 2. Corrected image. Note how histogram is extended to full tonal range.
white point setting eyedropper button on the right side of the eyedropper box (Fig. 1). 6. Place the eyedropper on a portion of the white labeler tape that has some color information. The area of reflection from the camera flash is washed out, and these pixels do not contain any information, therefore, select the matt part of the tape. Left click on the mouse, and the tonal range of the image will be automatically corrected. Visualize the correction in the image and the adjusted histogram (Fig. 2). 7. Save the image and process for distribution to the dental technician.
3. Benz C. Digital photography: exposures, editing images, and presentation. Int J Comput Dent 2003;6:249-81. 4. Singer BA. Digital photography: the key to the esthetic paradox. Pa Dent J 2001;68:19-26. 5. Goldstein MB, Young R, Bergmann R. Digital photography. Compend Contin Educ Dent 2003;24:260, 264-8, 270-3. 6. Dalin JB. Digital photography and imaging can enhance practice in several ways. J Indiana Dent Assoc 2002-2003;81:24-6. Reprint requests to: DR LAMBERT J. STUMPEL 450 SUTTER STREET, SUITE 2530 SAN FRANCISCO, CA 94108 FAX: (415) 362-0925 E-MAIL: [email protected] 0022-3913/$30.00 Copyright ª 2004 by The Editorial Council of The Journal of Prosthetic Dentistry
REFERENCES 1. Phelan S. Use of photographs for communicating with the laboratory in indirect posterior restorations. J Can Dent Assoc 2002;68:239-42. 2. Derbabian K, Chee WW. Simple tools to facilitate communication in esthetic dentistry. J Calif Dent Assoc 2003;31:537-42.
doi:10.1016/j.prosdent.2004.05.008
Receive Table of Contents by E-mail To receive the table of contents by e-mail, sign up through our Web site at http://www.mosby.com/ prosdent Choose E-mail Notification. Simply type your e-mail address in the box and click the Subscribe button. Alternatively, you may send an e-mail message to [email protected]. Leave the subject line blank and type the following as the body of your message: subscribe prosdent_toc You will receive an e-mail to confirm that you have been added to the mailing list. Note that table of contents e-mails will be sent out when a new issue is posted to the Web site.
AUGUST 2004
THE JOURNAL OF PROSTHETIC DENTISTRY 203
Photography may be an important tool in the communication between dentists and dental technicians; more so when these team members are not in the same location. Traditionally, the information carrier has been analog film.1,2 Increasingly, however, digital media are employed.3-6 The exposure variables are relatively similar for both analog and digital photography. The digital image has the advantage of immediate verification, so the intended exposure and framing can be evaluated. The darkroom process in the analog workflow has provided some control over the end product. Computer software is the digital darkroom. It allows quantification and controlled modification of a digital image. By analyzing an image, the software measures the quantity of all of the colors in an image. A histogram illustrates how pixels in an image are distributed by graphically illustrating the number of pixels at each color intensity level. The histogram indicates if the image has enough detail in the shadows, mid tones, and highlights. Pure black is situated on the left and pure white on the right side of the histogram. Shade communication is highly dependent on a true
image. It is imperative that the monitors used to view the image are color calibrated (Optical ColorVison; Pantone Inc, Carlstadt, NJ). Every computer monitor has a native colorcast; calibration ensures that this cast is corrected so the displayed image is true. This article describes a simple method to standardize a digital image used for shade communication with the dental laboratory.
PROCEDURE 1. Cut a 5-mm piece of 12-mm-wide black/white labeler tape (TC-20; Brother International Corp, Bridgewater, NJ). Remove the protective backing. 2. Wrap the tape, which functions as the white point for computer correction, around the metal holder just under the ‘‘ceramic’’ tooth portion of a shade guide tab (Lumin Vacum; VIDENT-CA, Brea, Calif). 3. Make photographs with the shade guide positioned parallel to the reference teeth. (s2Pro; Fuji Film Co, Ltd, Tokyo, Japan)
Fig. 1. Original image with corresponding histogram.
a
Private practice San Francisco, Calif; Director, Implant Prosthetics, Surgical Implant Training, Highland Hospital, Oral & Maxillofacial Residency Program, University of the Pacific, San Francisco, Calif; Assistant Clinical Professor, University of California San Francisco, School of Dentistry, Department of Restorative Dentistry, San Francisco, Calif. J Prosthet Dent 2004;92:202-3.
202 THE JOURNAL OF PROSTHETIC DENTISTRY
4. Open the images in the image processing software (Photoshop CS; Adobe Inc, San Jose, Calif). 5. On the toolbar select: ‘‘Image,’’ followed by ‘‘Adjustment,’’ followed by ‘‘Levels.’’ This will bring up the ‘‘Levels’’ box with the histogram. Ensure that the preview box is checked. Select the VOLUME 92 NUMBER 2
STUMPEL
THE JOURNAL OF PROSTHETIC DENTISTRY
Fig. 2. Corrected image. Note how histogram is extended to full tonal range.
white point setting eyedropper button on the right side of the eyedropper box (Fig. 1). 6. Place the eyedropper on a portion of the white labeler tape that has some color information. The area of reflection from the camera flash is washed out, and these pixels do not contain any information, therefore, select the matt part of the tape. Left click on the mouse, and the tonal range of the image will be automatically corrected. Visualize the correction in the image and the adjusted histogram (Fig. 2). 7. Save the image and process for distribution to the dental technician.
3. Benz C. Digital photography: exposures, editing images, and presentation. Int J Comput Dent 2003;6:249-81. 4. Singer BA. Digital photography: the key to the esthetic paradox. Pa Dent J 2001;68:19-26. 5. Goldstein MB, Young R, Bergmann R. Digital photography. Compend Contin Educ Dent 2003;24:260, 264-8, 270-3. 6. Dalin JB. Digital photography and imaging can enhance practice in several ways. J Indiana Dent Assoc 2002-2003;81:24-6. Reprint requests to: DR LAMBERT J. STUMPEL 450 SUTTER STREET, SUITE 2530 SAN FRANCISCO, CA 94108 FAX: (415) 362-0925 E-MAIL: [email protected] 0022-3913/$30.00 Copyright ª 2004 by The Editorial Council of The Journal of Prosthetic Dentistry
REFERENCES 1. Phelan S. Use of photographs for communicating with the laboratory in indirect posterior restorations. J Can Dent Assoc 2002;68:239-42. 2. Derbabian K, Chee WW. Simple tools to facilitate communication in esthetic dentistry. J Calif Dent Assoc 2003;31:537-42.
doi:10.1016/j.prosdent.2004.05.008
Receive Table of Contents by E-mail To receive the table of contents by e-mail, sign up through our Web site at http://www.mosby.com/ prosdent Choose E-mail Notification. Simply type your e-mail address in the box and click the Subscribe button. Alternatively, you may send an e-mail message to [email protected]. Leave the subject line blank and type the following as the body of your message: subscribe prosdent_toc You will receive an e-mail to confirm that you have been added to the mailing list. Note that table of contents e-mails will be sent out when a new issue is posted to the Web site.
AUGUST 2004
THE JOURNAL OF PROSTHETIC DENTISTRY 203