Advanced Telescope Supplies
Australia's Premier CCD and Astro-Imaging Experts

Why Buy an SBIG CCD Imager from ATS?

 

Advanced Telescope Supplies has been in association with SBIG for over 15 years and not surprisingly we have gotten to know a little bit about their products in that time.

We provide expert local support on all SBIG cameras and software

Still thinking about buying directly from the USA via the Internet? please fax or e-mail us your best quote (From an authorised SBIG dealer, yes even one in the USA). We will try to match or better it to get your business! 

Also here is SBIG's Official policy on cameras purchased direct from the USA

The new TWO year warranty on all SBIG products (*excluding CCD chips which are one year) applies only to products sold through authorized dealers in countries where we have exclusive arrangements (e.g. Australia).  Any US  dealer selling to one of these countries is now obliged to inform the  customer that there is no warranty on the camera and warranty repairs,  if required, will be at the selling dealer's expense, including  shipping.

Choosing a CCD imager can be a difficult task. It also has to be said there is a lot of conflicting information out there on "which is the best" CCD for a particular telescope. Also many amateurs have a problem with an accessory that costs as much, if not more than their entire telescope. SBIG make a range of CCD cameras that suit many needs and budgets. Hallmarks of the SBIG range are:

With their high dynamic ranges and quantum efficiencies, CCD cameras are changing the way many astronomers capture images and data from the night sky. 

A modest six inch aperture telescope equipped with a CCD camera will detect fainter objects than a 36" telescope with a standard photographic camera! 

Put that way, paying for an accessory that improves the detection ability of telescope by a factor of more than 30x is perhaps well worth the cost of the telescope itself!

Please call or e-mail us, or see SBIG's home page for more information about other SBIG camera models. Our $A prices are approximately SBIG's $US list converted to $A plus 15% to cover GST and shipping.

 

 

Digital Imaging choices.

 

 

 

Astronomy CCD manufacturers have pioneered many technologies that have been fine tuned for astronomical imaging and research for close to 20 years. But for many telescope users, the benefits of these features may not be obvious or hard to justify on a cost only basis.

 

Comparatively recent digital SLR technology is improving from year to year, and as their cost base falls along with improving performance, there is no doubt that using these cameras for astronomical imaging can give good results. 

 

While absolute image quality remains clearly superior with dedicated CCD systems, if picture taking is your only goal, reasonable astro-images can be obtained obtained by stacking dozens of exposures taken with DSLR's.

 

There are some hidden costs with DSLR astro-imaging which should be factored in the cost of imaging system eg:

 

It should be noted CCD imagers, as opposed to a "camera"  have other functions, features and options that are simply not present an never likely to be implemented with DSLR's

When considering a digital imaging system some factors will be more important to some, and less so to others. We hope that the information provided here will help with your decision making.

 

 

Below: CCD image of M8 (left ) compared to a Canon 350D DSLR image (right) taken through the same telescope.

 

 

Despite a short exposure time, the superior sensitivity of a CCD (at right) becomes very obvious with nebulosity (H-Alpha) and faint objects.

 

The images shown above demonstrate how  current model "real world" performance varies with each camera on relatively bright astronomical objects. Both image used the same F-ratio and were taken within a few minutes of each other on the same night.

The images are comparable in some ways, but very different in others. To comment further, the dedicated astro-imaging CCD camera clearly has

In terms of cost, CCD there is no hiding the fact that systems are more expensive, and likely to remain so due to the specialist nature of their design and inclusions:

Each SBIG ST-XE camera system INCLUDES at no additional cost:

 

Our tests have shown by increasing the DSLR exposure time by approximately a factor of 4x. image quality becomes comparable to the dedicated CCD, but not with faint objects (e.g. galaxies) as this relationship is no longer valid. The intrinsic noise in the DSLR then begins to dominate over very faint objects, and requires exposure 32x to 64x times that, yet still remain camera noise limited for very faint objects.

 

Increasing the CCD exposure times by a factor of 4x that above results in a significant image density improvement as well, but more importantly, the noise in the image still remains very low when longer exposures are taken.

 

 

SBIG CCD features.

 Autoguiding and self guiding

 

All SBIG CCD cameras can be used as auto-guiders. The native auto-guiding algorithm used by SBIG (hardwired in the model ST4 ansd STV’s and with every copy of CCDOPS) is so accurate any reliable that it has been in use in stand alone auto-guiding systems for nearly 20 years, and has been used to guide instruments such as the UK Schmidt Telescope.

All SBIG STL and ST7 through 10 series cameras have two independent CCD’s in the same camera head.  Guiding may be done with either CCD, but is usually done with the smaller guide chip.   This configuration virtually guarantees perfect guiding as it uses the image data from the main optical system (i.e not a separate guide telescope which can flex independently) and compensates for any movement in the imaging optics. 

Telescope aberrations aside, perfectly guided star images are a hallmark of SBIG dual CCD cameras.

 With monochrome SBIG cameras the guide CCD does sit behind the filter wheel assembly, however finding a suitable guide star is rarely a problem, as the guide CCD is extremely sensitive and the camera head can positioned at any angle for guide star acquisition.

 For very narrow band filter users or guiding on objects such as comets and minor planets all SBIG STL and ST7 through 10 series cameras are also fitted standard with remote guide head ports. The optional remote guide head needs no other electronics other than the main camera and can be used with guidescopes and SBIG’s E-finder assembly if desired

Science Applications

 SBIG have a range of integrated accessiories and filter sets that are unmatched by any other manufacturer. These include up to 10 position filterwheels, adaptive optics and high resolution self-guiding spectrographs. Integration is seamless, no other parts or software are required for their operation.

 Many CCD’s (even some SBIG models) are fitted with anti-blooming gates (ABG’s) which bleed off charge from the device before it saturates. This can make photometry a challenge as incoming data becomes non-linear and of little value at that point. 

SBIG offer an extended range of full frame non-ABG sensors that are fully linear in their responses to incoming starlight right up to full well capacity.  

In addition SBIG CCD chamber cooling is extremely repeatable and accurate. As a result image data that can be calibrated to a very high precision allowing photometry to 1/1000th of a magnitude using SBIG’s MILLIMAG or third party software.

Sensor sensitivity and resolution.

Nearly all  of the SBIG camera range is based upon full frame monochrome Kodak sensors. These have consistently higher peak quantum efficiencies compared all interline devices. and single shot colour devices.

Kodak full frame sensors have a range of pixel sizes (from 6.8 to 24 micron) and while rival manufactures may claim higher resolutions based on 6.4 micron technology.

This is false.

These devices are Bayer matrix based based, hence the first adjacent pixel that is capable of sensing light without being interpolated is 6.4 micron away, hence pixels have approximately a minimum 12.8 micron width not 6.4.  Bayer matrix based (single shot colour) cameras use a interpolative method to estimate the colour of adjacent pixels, which does not always work well with point like source data (eg Stars) often resultion in fine colour fringes around high contrast points.

The same is not true with full fame devices. Each and every pixel is used to capture incoming light.

 

 

 


Santa Barbara Instrument Group  (SBIG) ST series CCD cameras  


 

ST7USB2.jpg (144526 bytes)

 

FASTER DOWNLOADS
New high speed electronics and high speed USB interface are now standard with data transfer rates up to 421,000 pixels per second!

usb_electronics1.jpg (56818 bytes) High Speed USB
Download Rates		 ST-2000XM ST-7XE ST-8XE ST-9XE ST-10XE
Full Frame 5 sec. 1 sec. 3.7 sec. 0.7 sec. 8.7 sec.
Focus Mode ~0.5 sec ~0.5 sec ~0.5 sec ~0.5 sec ~0.5 sec
Note: USB download times are processor dependent and will vary from computer to computer.  These download times were measured on a 933 MHz Pentium III.   Focus Mode rates were the fastest achieved using a 20 x 20 pixel subframe in Focus / Planet mode.

USB upgrades are also available for existing parallel based ST-7/8/9/10 cameras.  See details below.

BETTER COOLING
The standard single stage cooling design has been improved to provide cooling performance previously available only with an optional second stage cooling booster.  Preliminary specifications are as follows:

usb_cooling4.jpg (52803 bytes) Cooling Performance (delta from ambient) Typical Minimum Previous design
Standard single stage with water assist -45o C -40o C not available
Standard single stage without water -35o C -30o C -25o C

The standard cooling configuration is a single stage cooler with a newly designed heat exchanger that includes an inlet and outlet for water circulation should the user desire to maximize the cooling performance for hot climates.  The new design does not require an additional power supply and may be operated with our without water supplied by the user.  A circulating water pump and tubing are available from SBIG as optional accessories.  In our experience, further cooling of Kodak CCDs beyond the performance above is unnecessary.    

GREATER EXPANSION CAPABILITY
All new production USB cameras and upgrades will include a bi-directional I2C accessory port.

usb_I2C2.jpg (32775 bytes)

The new I2C accessory port adds bi-directional communication capability for the development of a new family of "smart" accessories.  The standard accessory port is also provided in order to maintain backwards compatibility with our existing accessories (CFW8, AO-7, Relay Adapter Box) and customer's existing telescope interface cables.

COMPLETE SYSTEMS
It is the little things that count: 

usb_system2.jpg (39675 bytes)

These cameras are complete systems.  There is no need to add in the additional cost of an interface or an autoguider or a nosepiece or better software to make these cameras actually operate as they should.  Everything that is needed to make these camera systems operational is included in the base price.  We even include some non-essential, but desirable, items such as a custom hard carrying case and extra nosepiece.

MORE OPTIONS

SBIG continues to explore new methods and accessories to make professional quality imaging an achievable standard for amateurs. 

usb_accessory5.jpg (41723 bytes) usb_accessory6.jpg (25558 bytes)

SBIG is the only company offering adaptive optics and a self-guiding spectrograph to the amateur astronomy community at an affordable price.   Both the AO-7 Adaptive Optics device and the SGS Self-Guiding Spectrograph are available to amateurs because of our patented dual sensor self-guiding camera design.  In the case of the AO-7, the smaller tracking CCD is exploited to monitor star motion and drive the AO-7's mirror at correction rates up to 50Hz.  The Self-Guiding spectrograph uses both CCDs in the camera head to provide simultaneous images of the object, slit location and spectra.   It then guides itself during the exposure to keep the object on the slit.

usb_accessory1.jpg (40093 bytes) usb_accessory7.jpg (50561 bytes)

The following options and accessories are available for the ST-XE and XM cameras:

PRICE vs. PERFORMANCE

We feel that if one compares ALL of the included parts, features and costs of the camera / autoguider system with any competitor, SBIG remains a leader in price vs. performance.  For example, just adding in the cost of an autoguider and premier software comparable to CCDSoftV5 could run well over $US1000.   Instead of charging $US50 extra for a nosepiece, we give you two.  Water cooling capability is now standard, as is high speed USB.  There is no extra charge for a custom hard carrying case, etc.

 

 

Back to homepage