Santa Barbara Instrument Group ST-i User manual

Model ST-i
CCD Camera
Operating Manual
Santa Barbara Instrument Group
a Division of Aplegen, Inc.
147-A Castilian Drive
Santa Barbara, CA 93117
Phone [phone] •Fax [phone]
Email sbig @ sbig . com •Web www . sbig . com

DECLARATION OF CONFORMITY
We, Santa Barbara Instrument Group, a division of Aplegen, Inc., 147-A
Castilian Drive, Goleta, CA 93117 USA, [phone], declare under
our sole responsibility that the Model ST-i CCD camera complies with Part
15 of the FCC Rules. Operation is subject to the following two conditions:
(1) this device may not cause harmful interference, and (2) this device must
accept any interference received, including interference that may cause
undesired operation.
____________________________________________________________
Note: This equipment has been tested and found to comply with the limits
for a Class B digital device pursuant to Part 15 of the FCC Rules. These
limits are designed to provide reasonable protection against harmful
interference in a residential installation. This equipment generates, uses,
and can radiate radio frequency energy and if not installed and used in
accordance with the instructions, may cause harmful interference to radio
communications. However, there is no guarantee that interference will not
occur in a particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be determined by
turning the equipment off and on, the user is encouraged to try to correct the
interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the receiver and the
equipment.
• Connect the equipment into an outlet on a circuit different
from that to which the receiver is connected.
• Consult the dealer or an experienced radio/TV technician for
help.
A ferrite clip on the tracker cable must be used when operating this
equipment.
You are also warned, that any changes to this certified device will void your
legal right to operate it.
Operating Manual for ST-i Series Camera
Revision 1.0
April 25, 2011

SBIG ST-i Manual
1
Table of Contents
1. Introduction .........................................................................................2
Getting Started..................................................................................2
Overview and Connections...............................................................3
Installing the Software on 32-bit and 64-bit Windows Systems.......4
Migrating Old Drivers from 32-bit to newer 64-bit Systems............9
2. Using the Camera Inside...................................................................11
Running CCDOps...........................................................................11
Getting Help.................................................................................... 11
Brightness and Contrast..................................................................14
Establishing a Link ......................................................................... 15
Camera Info....................................................................................16
Camera Setup..................................................................................17
Grab Command...............................................................................18
Focus Command.............................................................................19
3. At the Telescope.................................................................................21
Finding and Centering the Object...................................................22
Taking an Image .............................................................................22
Further Adventures.........................................................................22
4. Acessories for your CCD Camera....................................................23
Tripod Mounting Ring....................................................................23
Camera Lens Adapters....................................................................23
5. Glossary..............................................................................................25
Appendix A – Connector and Cables......................................................29
Telescope Jack................................................................................29
Appendix B – Camera Specifications......................................................30
Appendix C – ST-i Color Camera Supplement......................................31
Appendix D – Dimensions and Backfocus ..............................................39

SBIG ST-i Manual
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1. Introduction
Congratulations and thank you for buying one of our ST-i CCD cameras.
The ST-i has the following features:
• Uses Kodak’s microlensed, KAI-0340 CCD with 648 x 486, 7.4
micron square pixels.
• 16-bit A/D converter with correlated double sampling .
• Single board, small, compact design with internal mechanical
shutter allowing automatic dark frames, and electronic shutter for
exposures down to 0.001 seconds.
• USB 2 interface yielding up to 2.0 megapixels per second
digitization rates with full backward compatibility with USB 1.1
computers at 400 kilopixels per second.
• Input power provided through USB port.
• Telescope interface with four optically isolated normally open
signals on the industry standard RJ-11 jack.
• 1.25" eyepiece sized barrel with threads for standard 1.25" filters.
• Optional c-mount, t-thread and camera lens adapters available.
• Powerful yet intuitive CCDOps software for guiding, image
acquisition and processing. Also comes with CCDSoftV5 and
TheSky version 5.
Getting Started
Very Important:
Before you attach the ST-i to your computer for the first time
you MUST install the software as described below
In addition to this Operating Manual, the ST-i package includes the
following items:
ST-i Camera – The camera body is approximately 1.25 x 3.5inches
USB Cable – Included is a 15-foot, USB 2 certified, A-to-B type, USB
cable. USB has a limit of 15-feet but the range can be extended
with active boosters.
Tracking Cable – This cable looks like a simple “RJ-11 telephone cable”
but in fact is a “6-pin reversed RJ-11 telephone cable”. Telescopes
require 6-pin autoguider cables and reversed means that, unlike

SBIG ST-i Manual
ordinary phone cables, this one flips the order of the wires. You
can tell a tracking cable from an ordinary cable by noting that with
tracking cables the tines that lock the RJ-11 jack into the receptacle
are both on the same flat side of the cable or when the ends are put
side by side the colored wires inside are in opposite order on the
two connectors.
Software – We include several CD-ROMs with the ST-i but the most
important one is labeled “SBIG Software and Catalog”. This
disc contains the drivers and CCDOps software you’ll need to use
the camera.
Overview and Connections
GUIDE PORT: This is where you connect the supplied 6 conductor
modular phone style cable to the Autoguider (sometimes labeled "CCD")
input port on your mount when using the ST-i as an autoguider, or when
using Track & Accumulate with mount corrections (see the CCDOPS
Manual for details of this mode
USB and POWER: Attach the 15-foot USB cable to any USB port on
your computer AFTER you have installed the drivers and software for the
ST-i. The USB port also provides power to the camera.
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Installing the Software on Windows Systems
This section tells you how to do a fresh install of 64-bit drivers for SBIG
Cameras on your 32/64-bit Windows XP, Vista or Windows 7.
You should download and run the 64-bit Driver checker as described
below whether you are installing the ST-i camera on a 32-bit Windows
system such as XP, or a 64-bit version such as Vista 64 or Win 7.
1. Make sure no SBIG cameras are attached to your system.
2. Make sure your account has Administrator privileges then run the
SetupBitDriverChecker64.exe program to install the 64 Bit compatible
SBIG Driver Checker application on your system.
3. On 64-bit systems, find the icon for the SBIG Driver Checker by
opening the Start menu and typing SBIGDriver in the search box. The
icon should appear above the search box. Right click the icon and
select Properties then click the Compatibility tab. Click the “Run this
program as an administrator” as shown below and then hit the OK
button.
Note: Under Vista and Windows 7 there are 2 levels of administrator
privileges: one at the account level and one at the program level. To
properly install the drivers the Driver Checker application requires
both.

SBIG ST-i Manual
4. Run the Driver Checker application and it will ask you about any ST
Series Cameras (ST-7/8/9/10/2K) you may plan on using.
Prior to 2006 the ST Series cameras had only an internal Tracking
CCD. We call this the Classic Model. In 2006 we added the Remote
Guide Head capability to the ST Series and we call it the Pro Model.
The Driver Checker needs to know whether your ST Series camera is a
Classic Model or a Pro model. For the ST-i camera it does not matter
which option you select 5

SBIG ST-i Manual
5. After answering the Classic/Pro question above you'll see the following
dialog. The list of drivers shown may be different on your system but
it will generally indicate that no Installed Drivers were found and that
they all need to be updated.
6. Click the Update button and the Driver Checker will start to install the
SBIG drivers into your system.
7. Once the drivers have finished installing the Driver Checker will show
the following. At this point you can quit the Driver Checker.
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SBIG ST-i Manual
8. Now it's time to try out the new drivers. With your camera
disconnected from the PC, then plug it into the PC with the USB Cable.
In the lower-right hand corner of the screen you see something like:
Followed by:
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SBIG ST-i Manual
On systems running 32-bit Windows such as XP you may see this:
followed by the Hardware Wizard
9. Select "Install Automatically." If for some reason the Add New
Hardware Wizard asks you to manually locate the drivers then
navigate to the proper directory under the Driver Checker directory in
the Program Files or Program Files (X86) directory. There are 4
possibilities and you must choose the correct set of drivers. There are
directories for 32 Bit and 64 Bit drivers, based upon your version of
Windows and under them directories for Classic and Pro model
cameras.
10. Run CCDOps and verify that you can establish a link to the camera.
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SBIG ST-i Manual
Note: If you previously installed SBIG 32-bit drivers using the old 32-
bit Driver Checker program and now want to install 64-bit drivers
over the old installation, follow the procedure outlined below:
Migrating Old Drivers from 32-bit to newer 64-bit Systems
This section describes how to migrate drivers from the old 32-bit only
DriverChecker to the new 32/64-Bit Compatible DriverChecker64.
1. Uninstall the old DriverChecker software.
a. Run the Add or Remove Programs Control Panel in the
Start menu.
b. Click on the SBIG Driver Checker entry and then click
on the Change/Remove button.
2. Manually delete the old drivers files from the disk.
a. Delete the following files from the
C:\Windows\System32\Drivers directory:
sbigfldr.sys, sbiguldr.sys, sbiglldr.sys, sbigusbe.sys,
sbigusbi.sys
Some of these may not exist on your system but delete the
ones that do.
3. Manually delete the old drivers files from the Device Manager.
a. In the Start menu, point to All Programs, point to
Accessories, and then click Command Prompt.
b. At the command prompt, type the following command ,
and then press ENTER:
set devmgr_show_nonpresent_devices=1
c. Type the following command at the command prompt,
and then press ENTER:
start devmgmt.msc
d. In the View menu select the Show hidden devices
command.
e. Expand the Universal Serial Bus controllers section by
click on the adjacent “+”
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f. For each of the items listed below, right click on the item
then select Uninstall:
”SBIG USB Camera", ”SBIG ST-402 Camera", “SBIG
USB Loader", “SBIG ST-L Loader", “SBIG ST-402
Loader"

SBIG ST-i Manual
g. Quit the Device Manager.
4. Install the new DriverChecker64 software.
a. Use the installer that came with your camera or download
it from our web site:
<www.sbig com>
5. Run the DriverChecker64 software.
a. From the Start menu select the DriverChecker64 item in
the SBIG folder.
b. Answer the question about your ST cameras.
6. Click the Update button to copy the new drivers to your system.
Link your old cameras to the new drivers.
a. For each type of SBIG Camera you own (ST, STL, ST-
402), power up the camera one at a time and then attach it
to the PC with the USB cable.
b. When the Add New Hardware Wizard comes up select
“No, not this time” when it asks if it can connect to
Windows Update then click Next.
c. Select “Install the software automatically” and click
Next.
d. If Windows asks you for the best match select any of the
entries with Version 2.41.0.0 then click Next.
e. Click Finish and then you’ll have to go through steps b
through done more time for this camera.
f. Repeats steps athrough ffor each SBIG camera.
When you’re all done your camera should show up in the Device Manager
in the SBIG USB Devices section as shown below:
Updating CCDOps and Drivers
We are constantly adding new features and fixing software bugs in our
software, which is available for free download from our web site. You
should periodically visit our website to check for updated versions of the
CCDOps software and you should also periodically run the Driver Checker
to download and update your drivers. To find the latest software and
drivers, go to:
http://www.sbig.com -> Software Downloads
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SBIG ST-i Manual
2. Using the Camera Inside
When you first receive the ST-i it’s wise to get acquainted with its operation
inside the house where it’s warm and not to try to struggle with the
telescope operation in the dark. We’ve included a brief tutorial below to get
you acquainted with the ST-i and the CCDOps software.
Running CCDOps
Once installed, it’s easy to run CCDOps from the Windows Start menu.
Click the Start Menu, then find the SBIG Folder, which under Windows
XP is under the All Programs section. Finally click the CCDOps Icon to
start the program. You’ll be presented with the startup About Dialog that
shows the SBIG logo and the version of CCDOps. To dispense with it click
anywhere in the dialog other than the two blue fields or simply wait and the
dialog will close itself.
Getting Help
CCDOps includes an extensive help file that can be accessed through the
Help Topics item in the Help menu. In addition many of the
dialogs have an embedded Help button that will take you to the
Help Topic for that specific command. Just remember, help is
always just a click away.
Opening and Inspecting Dark Frames
We’ve included some sample images on the SBIG Software and Catalog
CD-ROM to get you acquainted with what you should expect from your
camera.
First, let’s look at what is called a dark frame. In the File menu use
the Open command and then navigate to the CD-ROM’s Images directory.
Double-click on the ST-i Tutorial folder to show its contents. Finally
double-click on the Image 1 – Sample Dark Frame icon to open the image.
CCDOps will present you with a dialog listing all the parameters
associated with the image such as the Exposure Time, the Date and Time
the image was acquired, etc. Note that the Exposure Time was 1.0 second.
Spend some time inspecting the data then click in the dialog to close it.
Data like this is always attached to saved images and you can show it
using the Parameters command in the Display menu. After the Image
Parameters dialog has gone you’ll see the image displayed in its own
window and the Contrast dialog will appear. The image is shown below:
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SBIG ST-i Manual
This is what’s referred to as a dark frame and it’s what you get when you
take a picture with the nosepiece covered and the shutter closed. It’s a
picture in the dark. Although there’s not much interesting to look at in this
image there are some very important features that you need to understand.
The first thing you’ll see is that while the image looks mostly like salt
and pepper there are hundreds of bright specks. These are called hot pixels.
They are present in every CCD image to one extent or another, even in
images from our most expensive cameras. If your digital snappy camera
didn’t automatically remove them for you, they would be seen in those
images too.
What causes hot pixels? It’s an attribute of CCD sensors called dark
current. A pixel in an ideal CCD, in the absence of light, would maintain a
steady value. When exposed to light the pixel’s value would increase in
response to the light but then as soon as the light went away the pixel would
maintain its value again.
In the real world CCD pixels suffer from the affects of dark current
whereby the pixel’s value slowly increases (brightens) over time. All the
pixels in the image shown above have some component of their signal due
to the build up of dark current.
Dark current builds up over time in a linear fashion. Cameras designed
for taking long exposures provide TE cooling of the CCD to reduced the
rate at which it accumulates. However, for the typically short exposures
used in planetary imaging and guiding, cooling is unnecessary if the camera
can otherwise take and subtract dark frames.
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SBIG ST-i Manual
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Hot pixels are simply the pixels where the dark current is higher than
the average and thus they show up as white specs against the salt and
pepper background. Again, this is completely normal for CCD images.
The second effect you’ll notice is a brightening on the left of the image,
as if something bright was just outside the field of view. This is called the
readout glow and is caused by the electronics in the CCD, in particular by a
very small but ever present glow emanating from the on-chip amplifier that
conditions the weak signals in the CCD so that they may be digitized.
The readout (or digitization) of images from CCDs is a sequential
process whereby every pixel is digitized one-after-another until the whole
image has been digitized. The readout starts at pixel (1,1) in the top-left
corner and proceeds to pixel (648 x 486) in the lower-right hand corner. As
each pixel in a row is readout the pixels to the right of it within the same
row are shifted to the left one position in preparation for the next pixel's
readout. The next pixel is then readout and the process repeated until every
pixel in the first row has been digitized.
At this point the whole CCD is shifted up one row and digitization
starts with the left-most pixel of the second row. The readout glow on the
left of the images is a buildup of light from a glow from the preamplifier
structures in the upper-left hand corner of the CCD while rows are queuing
up for readout.
The final effect you’ll notice is the salt-and-pepper look of the
background. What you’re seeing here is the ultimate noise floor of the
CCD whereby adjacent pixels have slightly different values due to noise in
the CCD and readout electronics. The noise in dark frames that have zero
exposure time is referred to as the read noise of the camera.
Fortunately for us there are very simple image processing techniques
we can use to eliminate the effects of dark current and readout glow.
Let’s open another image. Close the first image by clicking the X in
the upper-right corner then use the Open command in the File menu again
but, this time double-click on Image 2. Note in the Image Parameters
dialog that this image had an Exposure Time of 10 seconds. Click in the
dialog to close it.
Now this image has a whole lot more hot pixels! That’s because this
exposure was 10 times as long and the pixels built up 10 times the dark
current. It’s hard to even see the background through all the hot pixels.
About this time you’re probably asking yourself “How can I ever take
images with all these hot pixels?” The answer is simple. Because the build
up of dark current is a repeatable effect you can remove the effects of dark
current by taking two images, one with the shutter open (light frame) and
another of equal exposure with the shutter closed (dark frame). You then
subtract the dark frame from the light frame, and because the hot pixels and
the readout glow repeat from one image to another they are removed by the
subtraction.
Let’s see how this works. Close Image 2 and Open Image 3, which is
a 10-second light frame where you can get a hint of the object but the hot

SBIG ST-i Manual
pixels are definitely obscuring it. Now use the Dark Subtract command in
the Utility menu. This brings up the Open File dialog where CCDOps
wants you to select which image to subtract. Double-click on Image 2, the
10-second dark frame. The displayed image turns completely black! What
did we do? Did we destroy the image by dark subtracting? No we didn’t
but it’s time to learn something else regarding CCD images.
Brightness and Contrast
Images from the ST-i are 16-bit images meaning any pixel can have values
from 0 to 65,535 ADU where ADU is short for A/D Converter Units. Said
another way this means there are 65,536 possible brightness or gray scale
values that each pixel can have. In CCD lingo this is referred to as the
dynamic range. But computer monitors and our eyes can typically only
distinguish a hundred or so different gray scale values. How do we
accommodate the large dynamic range of CCD images with our computer?
The answer is through Brightness and Contrast adjustments of the
displayed image.
Getting back to our dark subtracted image and why it’s completely
black. Find the Contrast dialog shown
to the right and then click the Auto
checkbox. Magically our object
appears, and as promised, the hot pixels
and the readout glow are gone, replaced
by the object and the salt-and-pepper
noise. What did we do?
14
Click the small up and down buttons adjacent to the Back
several times and you’ll see the overall image brightness increase
By clicking the Auto checkbox we
told CCDOps to adjust the image
display to match the actual image’s
pixel values. Auto Contrast is a very
handy tool to have in your bag of tricks.
Just for fun click the Smooth checkbox in the Contrast dialog. The
noise in the image is greatly reduced. The Smooth option is handy when
for reducing the noise in underexposed images like Image 3.
Let’s explore the Contrast dialog further. Close the dark subtracted
Image 3 and when CCDOps asks you if you want to save the changes
you’ve made click No. Use the Open command again to open Image 4,
which is just like Image 3, but with a proper exposure.
The first thing to notice is that in the Contrast dialog the Back is set to
8,000 and the Range is set to 20,000. What does that mean? In short it
means that pixel values from 8,000 (Back) to 8,000+20,000 (Back +
Range) have been displayed using the monitor’s available gray scale.
Pixels with values 8,000 ADU or below are completely black. Pixels with
values 8,000+20,000=28,000 ADU or above are completely white. Finally,
pixels with values between 8,000 and 28,000 are shades of gray.
setting

SBIG ST-i Manual
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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 by connecting the USB cable
between the camera and the computer. At this point the green LED on the
back of the camera should be on.

SBIG ST-i Manual
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 your camera. It should say ST-i
in the status bar as shown above.
Camera Info
After establishing a link to the ST-i use the Information command in the
Camera menu and you’ll see a dialog box similar to the one 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-
i 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-i in the field. To make sure you have the latest
firmware periodically run the Driver Checker, which checks our
servers for later drivers and updates your system accordingly.
Serial Number – If you ever need to know this, here it is. It’s on the label
on the back of the camera as well.
Readout Mode Table – This shows the various readout modes the ST-i
supports. The High-resolution mode offers the full 648 x 486
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SBIG ST-i Manual
resolution with 7.4 micron square pixels. The ST-i also supports
binning whereby groups of pixels are combined to form a single
larger pixel. This reduces the resolution but increases the
sensitivity as larger pixels capture more light. The Low-resolution
modes utilize 2x2 binning as you can see by the Image
Height/Width and Pixel Size entries.
Finally, review the information presented, then close the dialog by clicking
in it.
Camera Setup
Use the Setup command in the Camera menu to see the ST-i Camera Setup
dialog shown below.
The key items in this dialog are described individually below.
Resolution mode – This popup controls the readout mode discussed in the
Camera Information section above. You can select the High or
Low resolutions modes directly but we recommend you start with
the Auto resolution mode. In Auto mode the camera uses the high-
resolution mode everywhere except in the Full Frame Focus
mode (discussed below) where it uses the low-resolution mode to
speed up the image throughput.
Reuse dark frames – This is a handy feature and you should set it to Yes.
What that means is that when you’re taking images where you
want to subtract dark frames the software will reuse a previously
captured dark frame if it’s the same exposure time and at the same
CCD temperature.
You can read about the other items in the Help but for now just leave them
set the way they are. Click OK to register your changes.
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SBIG ST-i Manual
Grab Command
Let’s take a dark frame with your new camera. If you haven’t done so
already, screw in the nosepiece and put the rubber cap on it. While the
shutter was designed to block light from the telescope for dark frames, it
can’t block flooding room light from leaking around the edges of the shutter
blade. That’s why you should cover it under bright light illumination.
Now, use the Grab command in the Camera menu and set the dialog as
shown below:
Here we’re asking for a 1 second dark frame of the full CCD. Click the OK
button and in a few seconds you’ll see an image that looks a lot like the
Image 1 from the tutorial. Hot pixels, readout glow and salt-and-pepper
noise, they’re all there. Congratulations: You’ve just taken your first dark
frame! That wasn’t so hard was it?
Let’s experiment with the settings in the Grab dialog. Try changing the
Exposure Time to 10 seconds and grabbing another image but this time
watch the LED on the back of the camera. It blinks while the camera is
exposing the image. That’s a handy thing to remember when you’re in the
observatory. Don’t bump the telescope when the LED is blinking.
Anyway, the new image should look just like Image 2. Try setting the
Exposure Time back to 1.0 and the Dark frame to Also. What happens
here is the camera takes a dark frame first, and then takes a light frame,
subtracting the dark frame from it. The result should be uniform noise
without hot pixels and without readout glow.
Had we had the camera on the telescope we would have seen the object
but because we had the nosepiece covered we took a dark subtracted image
of the dark. If you take enough of these, and stare at them long enough
you’ll see all kinds of patterns in the random noise, including even pictures
of Elvis!
You can read about the other items in the Grab dialog by clicking the
Help button, but in general the Grab command is used to take a single
image and optionally do an automatic dark subtraction.
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