Adjusting Camera Position And Image Magnification - CellScale BioTester User Manual

BioTester User Manual

Adjusting Camera Position and Image Magnification

The camera position can be adjusted using the knobs at the back and side of the camera
housing. If larger position adjustments are needed, the bolts that attach the camera to the mast
can be loosened to allow rotation of the camera housing.
Using the 75mm lens and lens spacers, it is possible to achieve a field of view ranging from 9mm
to 30mm. The details of the appropriate number of spacers and the required standoff are shown
in the table below. The image magnification can be changed by adding or removing spacer tubes
located between the camera body and the lens. Increasing the total spacer tube leng th will result
in higher magnification while reducing the tube length will result in lower magnification. Changing
the tube length will also change the working distance of the lens. To adjust the vertical position of
the lens and camera assembly, loosen the bolts that clamp the camera housing to the mast and
raise or lower the camera housing until the image is in focus. It is helpful to make sure the lens
focus ring is in the middle of its rotation so that fine tuning the image focus can be done once the
camera housing is re-clamped.
INCREASING THE TOTAL LENGTH OF THE SPACER TUBES WILL INCREASE
MAGNIFICATION (DECREASE FIELD OF VIEW) AND DECREASE WORKING DISTANCE
(STAND-OFF).
If the camera position or magnification is changed, it is important to capture a single image scale
shot. A glass calibration target or a ruler is acceptable for this purpose. The scale shot will be
useful later to characterize the size of test specimens or test specimen features.
As the table and graph also show, it is also possible to swap in a lens with a different focal length
to achieve a different range of magnifications. This data was collected using the family of fixed
focal length lenses available from Edmund Optics (the part numbers are shown in the table). The
camera has a C-mount connection, making it possible to mount a wide variety of optical
components to best suit any application. Currently, only the standard camera is supported.
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