Virtual Laboratory Instrument Training Series

Web Site Design
by
Dr. Glen A. Stone
South Dakota School of Mines and Technology
501 East Saint Joseph Street * Rapid City, SD 57701
(605)394-1284 * FAX (605)394-3369

© 2002 - Dr. Glen A. Stone - SDSM&T


Instrument: Olympus VANOX-T Microscope

Unsupervised Use of This Instrument Requires Passing an Instrument Usage Quiz
Instrument Location: MI 125


Table of Contents
Quick Links to Web Page Topics

  1. Vocabulary
  2. Instrument Users
  3. Faculty Mentors
  4. Safety!
  5. Report Injuries
  6. Prevent Damage
  7. Maintenance
  8. Instrument Operation
  9. Links to Support Instruments
    1. LECO Image Analysis System
    2. Links to Laboratory Handouts Prepared to Aid Student Learning
      1. Link to Sophomore Laboratory Microstructure Illustration Laboratory (MET 231)
      2. Link to Sophomore Laboratory Quantitative Metallography Handout (MET 231)
    3. Quizzes and Surveys

Typical Microstructures Studied in the MET 231 Laboratory Class


  1.  Vocabulary associated with this instrument.

Interrogate the instrument by placing the curser over various regions of the instrument.
Pop-up boxes will appear.
35 - mm Camera Specialty Filter Insertion Point Specialty Filter Insertion Point Pull Knob to Select Photo or Video Camera Adjust Spacing Between Eyes Each Eyepiece is Adjustable so as to Correct for Some Vision Correction, Thus Allowing Use of the Instrument Without Glasses. Video Camera Polaroid Camera Binocular Eye Piece Objective Lens Turret Camera and Lens Turret Control Select Camera -- Video or Film Projector Lens Selector Unused Camera Port Select Camera Port Pull Out for Bright Field Image Pull Out for Bright Field Image Insert Polarize- Cross Polarizer in Front of Microscope Below Binocular Pull Our for Green Filter Pull Our for Amber Filter Field and Aperture Irises


  2.  Who uses this instrument?

MET 231, MET 331, and MET 441/541 Lab Classes, CAMP, AMP, and Researchers


  3.  Who are the responsible faculty?

EMES Laboratory Mentors
Dr. Dana Medlin
Office: MI 104
Dr. Glen Stone
Office: MI 103


  4.  Safety!

  • There are no safety issues of concern associated with the Olympus VANOX-T Microscope.
  • Students are not allowed to work alone in the lab. Undergraduate and graduate The professor in charge must supervise students until the microscope-driving test is passed. There must always be a lab partner present when any equipment is being used in this laboratory.
  • A logbook is maintained for the Olympus VANOX-T Microscope. All users must sign the logbook as well as record lab resources and a start and finish time.


  5.  Report Injuries

Report any injury, no matter how minor, to the person supervising the laboratory. If this person is not available find the department chair or the department secretary. If there is a major injury requiring medical attention:
call 0-911
The nearest phone is located in the main entrance stairwell.


  6.  Past Damage

EXTRA-EXTRA Read All About It
Gorilla Syndrome strikes the Olympus Optical Microscope. Heavy handed operator rams 100x lens into sample cracking lens. Cost to the department: $3000.

Link to Proper Procedure to Ensure this Never Happens Again


  7.  Maintenance

  • Regular Scheduled Maintenance
    • The Microscope and Image Analysis System is Maintained by the Materials and Metallurgical Engineering Department.
  • Maintenance Expected of Student and Staff Users
    • Each student using the equipment must replace all tools and other resources used into their proper place for the next user. Make every effort to maintain a clean and efficient working space.


  8.  Instrument Operation Instructions

Quick Links to Instrument Operation Topics
  1. Turning the Instrument ON or OFF
  2. Placing Specimen in Microscope and Changing Objective and Projector Lenses
  3. Adjusting of the Field and Aperture Iris Diaphragms
  4. Microscope Setup for Photography -- No Image Analysis
  5. 35 mm Camera -- Loading and Removing Film
    1. 35 mm Camera -- Loading Film
    2. 35 mm Camera -- Removing Film
  6. Polaroid Camera -- Loading and Processing Film
  7. Setting Up and Using the Light Meter and Camera Controls
    1. Xenon Lamp Rheostat Settings and Light Meter Readings for a Typical Specimen
  8. Magnification Calibration
    1. Magnification Calibration Table for 35 mm Camera


Turning the Microscope and Image Analysis System ON and OFF
  • All the component parts of the Microscope and LECO Image Analysis System are left ON and are connected to a main power strip. The power strip is located on the tabletop behind one of the monitors.
  • Turn the power to the system ON when starting, and OFF when finished by using the ON-OFF on the power strip.
  • If there is no power to the microscope make sure the green main power switch is ON, and also check that the gray illumination system power button is pushed in, and therefore set to Photo .
  • These are normally left ON because all power is controlled from a central power strip.
  • The light path pull knobs are always set for reflected light when using the servo-driven stage. The correct settings are provided on the photograph.
On-Off Switch
Depress Gray Switch for Photo Intensity
Pull Knob position is OUT for reflected light microscopy. With the automated servo-stage installed the transmitted light path is blocked. For transmitted light photography it is necessary to install the manual stage. Please see Dr. Marquis or Dr. Stone for help.
  • These switches are located on the right side near the back of the microscope housing.

  • Placing a Specimen in the Microscope and Changing Objective and Projector Lenses
    Placing the specimen into the viewing area of the microscope is critical with regard to eliminating damage to the lenses. Note the clearance between the lenses, as the lens magnification is increased is decreased.
    5x lens 10x lens 20x lens 50x lens
    It is required that the following procedure be followed to ensure no damage to the lenses.
    • Rotate the turret so the 5x objective lens is in place
    • Then place the metallographic specimen into the viewing field
    • Focus the specimen
    • Now if the turret is rotated to another lens, the lens will clear the top of the sample, and the specimen area should still be in focused.

    Attempting to place the sample in the viewing area for any of the higher magnification lenses, with the lens out of the focal plane can cause the next higher magnification lens to plow into the specimen when the turret rotation is activated. The probability of damaging the lens is very high.

    The 50x lens is already damaged with the lens mount pushed into the lens barrel. The lens still works, but the focal plane has shifted. When the turret is rotated from the 20x lens that is in focus to the 50x lens position, the image will not be in focus. Carefully refocus by rotating the fine focus counter-clock-wise.
    Video Illustration of Lens Turret Rotation
    Dial-up Modem
    LAN or Cable Modem
    Video Illustration of Setting Projector Lens
    Dial-up Modem
    LAN or Cable Modem

    Adjusting of the Field and Aperture Iris Diaphragms
    • Adjusting the field iris:
      • select an objective lens and focus the image,
      • remove one of the eyepieces, and
      • rotate thumb field knob until 20 ∼ 30% of the exit pupil area is covered.
    This procedure assures optimum objective lens performance.
    • Reducing the area of the aperture diaphragm reduces the angle of divergence of the light radiation, thus tending to increase the sharpness and contrast of the image.
    • When using high contrast, fine grain size, black and white film, additional contrast can be obtained by inserting either the green (G) or orange (O) filters.

    Microscope Setup for Use of the 35 mm and Polaroid Cameras
    • Microscope pull knob positions for standard photography. The pull mirror and filter control knobs must be in the position shown in the three photographs below.
    The two slide knobs are IN on the left side of the microscope.
    All the slide knobs are IN, with the exception to the two in the right most photograph.
    The two Bright Field knobs are normally pulled OUT for typical metallographic photographs.
    Left Side of the Microscope
    Right Side of the Microscope
    Close-up View of Right Side of the Microscope
    ←  The top gray switch activates the 35 mm camera mounted on the left side of the microscope housing.

    ←  The center gray switch activates what is currently a vacant camera port on the right side of the microscope housing.

    ←  The bottom gray switch activates the Polaroid camera.

    You are ready to load the 35 mm camera with film.

    Polaroid film is not provided for either graduate or undergraduate laboratories. The reason is the high cost of Polaroid film.
    Loading Film in the 35 mm Camera

    At least three or four times a year a student informs the faculty that all the pictures for a project did not come out. No film was exposed! Follow the procedure below and this disappointing result will not occur.

    1. To open the camera door simply lift (gently) the knob at the left edge of the camera.
    2. To load the film slide the thin strip of film fully into the notch on the film take-up reel located at the right interior of the camera body.
    3. Gently holding the film so it can’t slip from the take-up reel notch, pull the film cartridge until it can be set into its place at the left interior of the camera body.
    4. Gently push down, and rotate if necessary, the knob used to open the camera door. The knob should drop into the top of the film cartridge and be flush with the top of the camera.
    5. Close the camera door.
    6. Make two exposures by pushing the lime green “EXPOSE” button so film is wrapped around the take-up reel and also so unexposed film is in place for the first photograph.
    7. Gently rotate the knob on top of the camera, in the direction of the arrow on top of the camera, to remove any slack in the film reel system.
    8. If the film is feeding, and there is no slack in the film take-up reel, the knob will rotate each time a picture frame is exposed. This is proof the film is advancing and all your photomicrographs will be recorded.
    Play Video Illustration
    (92 Second Movie Clip)

    LAN/Cable Modem Speed
    Dial-Up Modem Speed

    Removing Film from the 35 mm Camera

    The sequence of steps to rewind an exposed roll of film and then remove the roll of film from the 35 mm camera follows.

    1. The camera reel is locked so the electric motor can advance the film after each exposure. This is known because the red bar on small knob behind the camera body is vertical.
      To unlock the camera reel reach behind the camera body and rotate this knob so the red bar is horizontal.
    2. With the camera reel unlocked, raise the handle located in camera rewind knob and rotate in the direction shown on the top of this knob. When all the film is all wound onto the cassette the rewind knob will move freely.
      If you fail to rewind all the film into the cassette, the film not inside the cassette will be exposed to light and will be unusable.
    3. Gently pull up on the rewind knob, then remove the film cassette from the camera.
    4. Almost all film processing labs in the city will provide prints in one-hour or high-resolution digital images on a CD-ROM within 24 hours. Be sure to specify high-resolution. The resolution normally provided will be only 640 x 480 pixels.


    Loading and Processing Film in the Polaroid Camera


    The process of loading and exposing the Polaroid film follows.
    1. Move the selector bar (P or L) position to L (Load).
    2. Gripping the film packet by its outer edges, slide the film into the film cassette. An audible click will be heard when fully inserted.
    3. Grip the film packet by the tab, and slowly pull the paper film shield from the cassette. When a slight resistance is felt – STOP.
      If you are overly aggressive it is possible to separate the paper film shield from the film packet. This ruins the film and creates a mess. The camera usually must be taken apart. The ruined film must be removed and then the camera parts must be cleaned using alcohol.
    4. Expose the film, and then push the paper film shield back over the film.
    5. Move the selector bar (P or L) position to P (Process).
    6. Firmly grip the film packet tabs and pull with firm force and uniform speed.
    7. Follow the film processing instruction and negative preservation instructions provided with the film.
    Play Video Illustration of Polaroid Film Processing
    (66 Second Movie Clip)

    LAN/Cable Modem Speed
    Dial-Up Modem Speed
    The Polaroid film of choice by most researchers is Type 55 P/N (Positive/Negative Film). Reason is instant gratification. Preservation of the negative requires a post processing in a sodium sulfite solution and a water wash treatment to remove the developing chemicals. This is followed by a treatment with Kodak’s Photo-Flo 200, and air-drying. The quality of negative is poor to fair with a large grain size. The large grain size limits the amount the image can be enlarged.

    Recommendation: if high-resolution black & white photography is the goal, the purchase one of several very fine grain-size 35 mm films is suggested.

    Setting Up and Using the Light Meter and Camera Controls

    RESET button sets the frame counter back to 1. Use this number to keep track of each image on the role of film. Use the DOUBLE ARROW tilt button to increase or decrease the film speed (ISO-ASA) number published on the film. When correct push the SET button.

    RECIPRO Button: Film sensitivity varies with the exposure time and illumination level. This variation is called reciprocity effect. More information below.
    The EXPOSURE ADJ button provides a manual method to adjust the film exposure time. The EXPOSURE TIME is the exposure time either set by the operator or automatically set by the microscope's light meter.

    If the LOCK button is pushed all your photographs will all have the same exposure time on display(rarely used).

    The RECALL button sets the previously set exposure time.
    The EXPOSE button activates the shutter.

    If the safety light flashes the light intensity is too high for the fastest camera shutter speed. Reduce the light intensity before attempting to take a photograph.
    The MANUAL button provides for time exposures. Press the Manual button, then press the EXPOSE button. The exposure clock starts and records the time the shutter is open. To close the shutter press the TIME OFF button.

    The NO WINDING button will close the shutter without advancing the film. This feature provides a method to produce double exposures.
    The SPOT button causes the light meter to measure the intensity, and thus compute the exposure using the center 1% of the image. Use mainly in dark-field photography.

    The DOUBLE ARROW tilt button activates the four lens turret causing a different lens to rotate into position.
    Reciprocity Law: Normal use of commercial films is at shutter speeds between 1/1000 to 1/5 second. For this exposure range the Reciprocity correction is zero stops. In Metallography it is common to have 1, 10 or even 100-second exposures. In this exposure time range, the Reciprocity Law fails to describe the film sensitivity. The number set in the image above is 3 stops. This number may not be realistic for the film you have chosen to use. Specific Reciprocity correction data may be provided in the film package, but can always be obtained from the Kodak Web Site for almost any black & white or color film available. A Kodak document that provides data (requires ADOBE Acrobat Reader) is provided here.
    Reciprocity Data

    Xenon Lamp Rheostat Settings and Light Meter Readings for a Typical Specimen
    • The first four-xenon light intensity levels associated with four of the eleven possible rheostat positions.
    • As the exposure time increases the reciprocity correction factor for the film being used becomes more important.

    Magnification Calibration
    • The instrument to the left is used to calibrate the magnification. It is called a stage micrometer. The surface of polished Stellite is engraved with 100 equally spaced lines in one millimeter.
    • The image to the right was taken using the 35 mm camera, the 50x objective lens and the 2.5x projector lens. If the photographic print is 3.5 x 5.0 inches, the image magnification is 483x.

    Magnification Calibration Table for 35 mm Camera
    Magnification Chart for 35 mm Camera
    Photographic Print Size is 3.5 x 5.0 inches
    Objective Lens Selection
    Projector
    Lens
    Selection
    X
    5
    10
    20
    50
    100
    2.5
    48.7 97.1 193.8 483.2
    966
    3.3
    64
    128
    255
    639
    1277
    4.0
    78
    155
    309
    774
    1548
    5.0
    97.3 193.5 384.2 968.7
    1937
    Bold Magnification Numbers Were Obtained By Using the Stage Micrometer
    All the Others Magnification Numbers Were Generated by Interpolation


      9.  Link to Quiz and Web Site Evaluation Form

    • If you are enrolled in MET 231, 331 or 441/541 the Username and Password is your student ID number.
    • If you are working on a CAMP or AMP project and enrolled as an graduate or undergraduate student, contact Dr. Stone via email. Your Password and Username will set as your student ID number.
    • If you are a visitor, email or contact Dr. Stone directly. A temporary Username and Password will be provided.
    Unsupervised use of this equipment requires personal certification by Dr. Marquis or Dr. Stone, or passage of the qualifying quiz with a grade of 100%