The Battle of the CCD-Titans
Let me start this discussion with a legal disclaimer:
The following review is based solely on my opinions and judgment which may be less scientific than one would like but they do reflect what I believe a typical user would experience (so please don't sue me if you do not agree with my opinions or views). This review attempts to present a balanced and even approach to both FLI (Finger Lakes Instrumentation) and SBIG (Santa Barbara Instrument Group). As inferred above this is an end-user review and it is not an engineer’s perspective - I will leave the technical and mathematical analysis to others. Please also bear in mind that the two CCD cameras in review use a different CCD sensor from Kodak. Therefore some product specific advantages/disadvantages can be attributed to the Kodak sensor used while other advantages/disadvantages can be attributed to the camera design. The good news is that there is a clear winner in my opinion in this battle of the CCD-Titans…
I am lucky enough to own and use top of the line CCD’s from both Santa Barbara Instrument Group (an STL11000M) and from Finger Lakes Instrumentation (a ProLine09000). I also use an SBIG ST2000XM. I believe that my story will be informative for others. Read on for the details...
My wife surprised me with a Meade EXT90 including a Meade Lunar Planetary Imager for Christmas, 2004, and since then my passion for astronomy has only accelerated. Along with this passion comes the need to upgrade one’s equipment. I have purchased and sold a Meade LX200GPS, and it was during this period when I acquired the ST2000 and a color filter wheel and filters from SBIG. I had quickly outgrown the limited capabilities of the LPI. While I was excited and eager to begin astro-photography with the new ST2000, I was disappointed with the initial internal cleanliness of the ST2000. The day I first used the original CCD equipment from SBIG was when I came to understand the term “dust doughnuts”. When I made a call to SBIG, I was informed that this was quite normal with all CCD cameras, and it was recommended that I learn more about taking Flat Field images and doing reduction processing. Ok… I agreed that I did not want to send the new camera back to California just after I received it even though SBIG offered to clean it for me. I only wondered why it seemed like this had not been done before it was shipped to me?
As the months passed, I felt a need to upgrade the optics as well as the camera’s capabilities. So with the acquisition of new Takahashi telescopes I also purchase the STL11000 and new filters from SBIG. I was quickly learning the details of both astrographs and CCD’s. My 3 year equipment trail is somewhat littered, and you can see the details and technical comparisons on my website at ->
To keep this review focused on CCD’s I will only mention that my telescope manufacturer of choice is Takahashi.
I have now changed my preference of CCD-equipment supplier from SBIG to FLI. I made this change primarily because I was not fully satisfied with the quality of the class-1 Kodak sensor in the STL. Nor was I happy with SBIG’s responses to me about this issue even though they undoubtedly were always being technically correct. Here, for example, is an article that SBIG referred to me after I questioned the quality of the sensor (I did not receive this information during the pre-sales process) ->
I have tried to update the recommendations and technical information with accurate data on my website and in this article. However, there are still possibilities for error. I would be please to update any data which are shown to be inaccurate. I am also aware, as any reader should be, that it is not accurate to compare Bias, Dark, or Flat images that are taken at different temperatures on different dates etc. The Bias images on the website were taken at the temperature at which I normally use the cameras. The Bias images you can view on the website are .JPG images not the original .FIT images. FIT images would be far too large to view quickly over the internet. So I have tried, as accurately as I reasonably can (based on the visual observations at the time) to reproduce what the original Bias images looked like to me within a stretched, JPG image with reduced size for internet viewing. Given all these additional caveats, you can see the Bias images for these sensors at ->
Finger Lakes Instrumentation, LLC is a wonderfully managed company. Mr. Greg Terrance and his co-workers at FLI are truly knowledgeable, helpful and concerned about customer satisfaction. Not everything that I purchased from FLI worked perfectly the first time. But in contrast, FLI did everything in their power to correct the problems and make the customer (me) satisfied. The added cooling power of the ProLine seems to be able to eliminate most of the largest noise artifacts, at least in my experience. Try the link above again and view the FLI Bias image. The FLI darks and flats are just as good, by the way.
I purposefully selected the FLI ProLine09000 over the ProLine16803 since the 12µm pixel size was a better fit for my OTA. FLI offers a very wide selection of CCD sensors which can be placed within its ProLine family of CCD products. In addition to Kodak sensors, a user can select a sensor from E2V Technologies or Fairchild Imaging. Ask Greg about the relative costs.
FLI’s ability to quickly adapt to the new line of Kodak and other CCD sensors many months ago is also an obvious plus. FLI has just introduced its new MicroLine to complement its ProLine series of cameras and at lower costs. FLI has announced the New ProLine18000 imaging system.
At this point some may think that I have a financial interest in FLI, as my promise to be balanced might seem to be getting stretched a little. I am not being paid or compensated in any way from FLI, nor do I have any financial interest in FLI. But I trust that you can get my drift. Let me summarize my most important opinions about the FLI09000 and the SBIG STL11000:
1. The ProLine cools to about -60C below ambient (without water cooling), in my experience this is about 25-30C better than the STL. Here in Florida where ambient can be +25C or higher at night, this makes a huge difference in reducing unwanted noise.
2. Downloads of Bin-1 images happens in 2-3 seconds for FLI (using fast mode) vs. about 20 seconds for SBIG. FLI can optionally have reduced speed if excess noise introduced during the download becomes a problem. The rapid downloading is an obvious plus during auto-guidance.
3. The ProLine features a unique dual sealed chamber system. Both the camera electronics and sensor are located in separate sealed chambers to keep moisture out and the camera's dry noble gas in.
4. The QE of the new Kodak09000 full frame senor is superior to the Kodak interlined chip in the STL
5. The pixel saturation level of the ProLine sensor is about twice that of the STL11000
6. The read noise is less in the newer Kodak chip in the ProLine09000
7. The FLI sensor window sits behind a 65mm shutter opening, vs. the STL which from my measurement has a maximum opening of about 55mm and is essentially for a 2” (50.8mm) nosepiece.
8. The filter wheels for ProLine cameras are an independent optional accessory. This is an advantage because it offers full flexibility of size, and numbers of filters. As CFW technology progresses, the CFW can be upgraded independently from the camera itself.
9. In my opinion, my own images are better and have less noise and artifacts with the new ProLine09000
SBIG’s advantages are:
1. The STL provides an internal or optionally remote guidance chip. FLI has no internal guider and requires a completely separate guider.
2. The STL has a built in filter wheel thereby bundling in the price for a CFW along with the camera. This is an advantage because it consumes less backfocus distance in the imaging train.
3. The shutter speed on the STL will operate at .001 of a second versus .01 seconds for the ProLine. I found this to be helpful when taking Flats during the daylight hours, for example.
4. The STL is shipped with an excellent Pelican carrying case; while there are optional accessories from FLI no case is included with the ProLine.
5. The STL has convenient rack handles.
When I bought my STL the price was under $9,000 (which included an internal, unpopulated filter wheel) vs. the ProLine09000 at around $10500 with no filter wheel.
I know that SBIG has a huge and loyal customer base, and I too have enjoyed and taken hundreds of great images with my SBIG cameras. I also know that SBIG is working on the roll-out of new and improved products. However, there are still FLI points or advantage 10, 11, and 12…. Customer Service, Customer Service, and Customer Service which is outstanding, in my opinion!
The clear winner is Finger Lakes Instrumentation.
June 15, 2007
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