PROCEDURE FOR CAMERA LAB 2

 

���� The following procedure should be used to perform those parts of the Camera Lab 2 experiments which require the use of a virtual oscilloscope (O-SCOPE).

 

Step 1 � Insure you have a light probe, a black cable, and a standard flashlight at your work table.� (Also, each person should have their camera !!)

 

Step 2 � Connect one end of the cable to the light probe.� Connect the other end of the cable to the back of the computer on �Ch 0�.� (The rightmost of the three larger round connectors on the O-SCOPE card in the computer).

 

Step 3 � Double click on �Virtual Bench � Scope� on the desktop.

 

Step 4 � Load the default settings.� (You should to do this twice to insure the default settings have been completely loaded.)

-         Edit � Load Settings

-         Select �default.sco�

-         � Open

 

Step 5 � Make sure �Run� is in the OFF position when you are changing settings.� Only �Ch 0� should be active for this experiment.

 

Step 6 � Set the �Timebase� to 2 mSec/Div.

 

Step 7 � Set the �Volts/Div� to 5V.

 

Step 8 � Set the Trigger Source (Src) to �Ch 0�.

 

Step 9 � Set the Trigger level and it�s position in the timeline.� This is denoted on the screen by a small + symbol.� You will need to start with the Trigger centered.

-         � Controls � Trigger � Center� (Repeat until + is centered)

-         � Controls � Trigger � Increase� (Repeat until Trig 2V)

-         � Controls � Trigger � Move Left� (Move to 1st vertical grid line)

-         Note: The quick keys may be helpful.� (ie.� Shift + � )

-         The screen should look like something like this:

 

Step 10 � Click on �Single� to enable the capture.� Before you begin you may want to press the button on the probe and shine the flashlight in the end to test your settings.� You should see a square wave that starts at the trigger mark.� If you experience difficulty you may need to reload the default settings or possibly restart the application and repeat the above steps.

 

Step 11 � You should now be ready to capture the shutter speed.

-         First, wind the camera shutter mechanism.� (Your TA will show you how.)

-         Turn on the flashlight and point it directly into the camera lens as shown.

 

 

-         Hold the light probe inside the camera carefully lining it up with the lens.

-         While holding the light probe button down, click �Single� then push the shutter release button.

-         Release the light probe button and remove the light probe from the camera.

-         You may need to do this a few times to get good results.

-         The capture should look something like this:

 

 

Step 12 � Record your results and repeat this for each camera in your group.

-         For printing you will want to change the Background to white, the Foreground to gray and the �Ch 0� to Black.� This can be done by:

o       Edit � General Settings � Display

o       Modify Background and Foreground setting appropriately and Apply.

o       Edit � Channel Settings

o       Modify the �Ch 0� color under the Acquire tab.

-         You can capture the active window by pressing �Alt+Print Screen� and pasting the image to Word.� Be sure to label each plot.� (Save your work!)

 

Step 13 � Capturing the Flash duration.

-         You will need to change the Timebase but the other settings should remain unchanged.

-         Remember �Single� needs to be OFF to change settings.

-         Set the Timebase to 500mSec/Div.

-         While holding the light sensor button down, direct the flash at the end of the light probe.� You should hold the light probe at least two hand-spreads in front of the camera flash bulb.

-         Record your data as you did in Step 12.