SBIG ST-402 Operating Manual
Page 10
and decrease. Click the ones adjacent to the
Range
setting and you’ll see
the image
contrast
increase and decrease. Here’s a summary of how this
works:
Increasing the
Back
decreases the image
brightness
and vice-versa.
Increasing the
Range
decreases the image
contrast
and vice-versa.
Set the
Back
to 8,000 and the
Range
to 20,000 by typing in the fields
(without the comma) and then hit the
Apply
button to get us back to where
we started. When you manually enter values in the
Back
and
Range
you
must hit
Apply
to see the effect.
Let’s learn a little more about the controls in the
Contrast
dialog. Click
the
Invert
checkbox and notice that the image now looks like a negative.
For images of faint objects, viewing the image as a negative by clicking
Invert
can reveal faint structure.
Unclick
Invert
and then click
Sharpen
on and off several times while
looking at the fine detail in the image. With the
Sharpen
checked it’s
almost as if the focus improves. That’s the effect of Sharpen. It works
great on well-exposed images but tends to increase the noise in faint areas.
The last thing to try in the
Contrast
dialog is the
Mag
popup. It’s set to
1:1
but selecting
2:1
or
4:1
zooms in on the image, enlarging the image
display. Selecting
1:2
or
1:4
zooms out on the image. Try the
1:2
and
2:1
settings. You may wonder if all these changes to the
Contrast
dialog are
destructive to the image data. They are not.
Changes to the settings in the Contrast dialog only affect the way the image
is displayed. They
do not modify
the actual pixel values.
In Summary
•
Clicking
Auto
is a good place to start with most images.
•
Back
controls image
brightness
and
Range
controls
contrast.
•
Clicking
Invert
can help reveal faint detail in images.
•
Clicking
Smooth
can reduce the noise in underexposed images.
•
Clicking
Sharpen
reveals additional detail in well-exposed images.
Establishing a Link
It’s time to actually connect up to your camera and take some images. If
you haven’t installed the drivers already go back to
Section 2
and do so
now.
If you’ve taken a break from the tutorial and the camera isn’t powered
up and attached to the computer do so now buy plugging in the power
source and then connecting the camera to the computer. At this point the
Fan
and
LED
on the back of the camera should be on.
SBIG ST-402 Operating Manual
Page 11
Use the
Graphics/Comm Setup
command in the
Misc
menu to make
sure
USB
is selected for the
Interface
. Click
OK
to set/confirm that and
then use the
Establish COM Link
command in the
Camera
menu.
CCDOps will try to connect to your camera, which can take several
seconds to complete. If successful you’ll hear the shutter emit a series of
clicking sounds as it finds home and you’ll see updated information in the
Link Status
fields show in the lower-right corner of the CCDOps window
as shown here:
This shows the link has been established to an ST-402, that the Temperature
of the CCD is 18.48°C and that the TE cooling is disabled (0%). The
clicking is not a death rattle – it is simply the shutter homing against a stop.
Camera Info
After establishing a link to the ST-402 use the
Information
command in the
Camera
menu and you’ll see the dialog shown below;
The
Camera Information
command shows you the capabilities of your
camera. There are a few key items here that you should be aware of should
you ever need technical support:
Firmware Version/Driver Info
– Over time we revise the camera firmware
and drivers to add new capabilities and fix software bugs. The
ST-402 actually has its firmware downloaded to it every time it
connects to the PC after a power-up sequence, which makes it very
easy for us to update the ST-402 in the field. To make sure you
