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content
copyright © 1995-2002
RedShirtImaging, LLC.
Website Design by
Elizabeth
Nephew
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Initial
Start-up Procedures
2.
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Turn on camera (switch on power supply)
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3.
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Start the NeuroPlex software
(click on NeuroPlex icon)
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5.
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Set the offsets
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>> CCD
Camera
The process of calculating and recording the offsets for a specific camera is done by us before
shipping it. Unlike some 8 bit A/D
cameras, once these offsets were set for the NeuroCCD-SM, there is no
need to change them during the experiments. Moreover,
using 14 bit digitization one can resolve the dark noise in most gains
and rates. Thus changing the offsets is not very useful.
In
some rare situations, an experiment could be improved by reducing the
dynamic range (increase bit resolution) of the camera. If you believe
this is the case, and would like to change the offsets, please refer to
the help manual.
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6.
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Test the response to
light using the LED
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We have already tested
the camera with LED for synchronization. All the test files are stored
on the system computer in C:\Data\Camera_Test\ .
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7.
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Installing the
Optical Coupler
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About the Optical Coupler
The coupler has C-mount connections on each end. The end with the small
diameter lens is screwed into the SciMeasure
camera. The other end is screwed to a C-mount port on the microscope.
The following table identifies the four optical couplers that have been
supplied by RedShirtImaging.
Name
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Serial
#
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Magnification
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Length
(cm)
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C-1
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080799
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0.10
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21
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C-2
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092999
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0.08
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11
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C-3
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091301
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0.10
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11
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C-4
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091301R
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0.095-0.115
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11
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All four couplers have adjustments for focus
and centering. The C-3 couplers have an additional adjustment for image
quality. This adjustment allows the coupler to provide a high quality
image on many microscopes. (If image quality is a problem using a C-1
or C-2 coupler, please contact us.) The C-4 couplers have, in addition,
adjustable magnification (0.115 to 0.095X).
The C-1 or C-3 coupler that we sent with your camera is about perfect
(to our taste) on our Leitz Ortholux-II microscope. But, to make it perfect
we had to increase the inside diameter of the C-mount adapter on the
microscope to 21 mm with a lathe. This seems like a good thing to do
generally. Now the camera sees about 10% bigger field than the eyepiece
and only a small section of each corner is dark.
To reduce the field of view that the camera sees
by 50%, purchase a 2X amplifier (part # 29-30-42) from Thales-Optem, Fairport, NY, (585)
223-2370.
Note for Zeiss Axioscope 2FS microscope
users: The 1 X optic coupler/tube (part number 45 61 05) for mounting
CCD camera (small 30 mm camera port) comes with a removable ring (field
stop), which blocks a large portion of the visual field.
For coupler C-4 start by setting the magnification to 0.10.
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7.a.
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Focus Adjustment
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The focus adjustment
can be used to make the camera and the microscope eyepieces parfocal. Screw the coupler onto the camera so
that it is tight. This connection should not change.
- Focus on an
object using the eyepieces.
- Loosen the
two Allen screws on the part of the coupler closest to the camera.
- Using the
Acquire Continuously function in NeuroPlex,
rotate the part of the coupler closest to the camera until the focus is
sharpest. This mechanical manipulation is tricky. It can be difficult
to rotate, when the coupler is attached to the camera and microscope,
without twisting the cables to the camera head. This will work
relatively easy if the connection to the microscope can rotate without
changing the distance. Repeated testing after rotations with the
coupler detached from the microscope would be optimal.
- Tighten the
two Allen screws and the connection to the camera.
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7.b.
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Centering Adjustment
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The centering
adjustment is used to center the microscope image on the camera.
- Loosen the
three Allen screws on the part of the coupler just distal to the focus
adjustment.
- Using the
Acquire Continuously function, adjust the three Allen screws so that
the object is centered. Then tighten the screws. This process can be
tedious and also a bit tricky.
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7.c.
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Image Quality
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This adjustment (for
C-3 and C-4 couplers) can be made by loosening the Allen head screw on
the side of the coupler and moving the screw head while examining the
image using the Acquire Continuously mode. This adjustment should allow
you to form an image without "pin-cushion" types of distortion. If you
still have distortion problems after making the adjustment, contact RedShirtImaging.
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7.d.
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Magnification adjust
for the C-4 coupler
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Loosen the two "Mag"
thumb screws and slide the coupler up or down to change the size of the
image on the CCD. Following this change you must repeat the Focus and
Image Quality adjustments.
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8.
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Setting Camera
Amplifier Gain:
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It is recommended that the following
focusing procedures (8a and 8b) be done under low light levels to
minimize possible photo-bleaching or photo-damage to the preparation.
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8.b.
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>> Acquire
Continuously
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...and adjust
the microscope focus on the preparation. (You will need to have
adjusted the optical coupler first.)
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8.c.
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Close the shutter
and increase light level to maximum
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8.d.
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>> Acquire One
Frame
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Normally using
>> Subtraction (auto shutter control) and >> Auto (min/max)
to check that the light levels are neither too low
or too high.
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8.e.
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>> Histogram
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If the values
are < 0.5 volts, then you may be able to increase the
signal-to-noise ratio if you change the acquisition settings in a
direction to increase the values (i.e. use a lower frame rate and/or
high gain). Repeat step 8d then go
to step 9.
If the values are > 8.5 volts and appear piled up at a high-voltage
boundary, it is likely that many pixels are saturated. (Saturated
pixels will appear as flat traces when you take data.) Look for many
values between 9 and 10 volts. If it appears that there are a
substantial number of saturated pixels, change the acquisition settings
in a direction to decrease the values (i.e. use a faster frame rate
and/or lower gain). Repeat step 8d. If the values still appear
piled up at a boundary at 2000 fps and a gain of 1, then the only way
to avoid saturation is to lower the incident light intensity. (You can
use a faster frame rate than you need for your signal frequency and
still not save excessive data by using Temporal Bin after Acquisition.)
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9.
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Select the
acquisition parameters
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Most functions are
controlled in the left panel; the parameters in the center panel are
used for signal averaging. Additional information about the acquisition
functions can be found in the on-line manual.
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