Did SBIG ever make an ST-4000XM (mono)? I know about the ST-4000XCM one-shot color and the ST-2000XM/XCM mono/OSC, but I know I've seen references to a mono version of the 4000 (maybe an old SBIG price list). Such a camera would have used the Truesense KAI-04022 mono CCD without the Bayer filters.
Yes, there are ST-4000 monochrome cameras in existence. Of course these models are no longer in production.
Well they are really hard to find. The ones I've seen say they were specially modded by SBIG from the XCM version, which implies that they were never a true production model. When did SBIG make these?
We don't have all the records from that era. But you can do some research for yourself with this handy site: http://web.archive.org/web/*/www.sbig.com
Now that I own both an ST-2000XM with CFW-9 and an ST-4000XCM, I can answer my own question. There is no such thing as a monochrome ST-4000XM. It would have been an awesome camera, but SBIG never made it. This is because the KAI-4020/4022 chip in the ST4K is just too big for the 1.25" filters in the CFW series filter wheels. And the ST series camera body can't handle a 2" filter wheel. You have to go to the STL series to get a large format CCD with 2" filters. So there you have it.
Tony, I'm not sure what the end point is but, having been a SBIG Employee from 1999 to present (technically I'm not an actual employee now though), I can tell you with absolute certainty that the ST-4000XM model was manufactured and produced from 2007 all the way into 2012. Do I win anything?
Aha, the plot thickens. The mystery of the missing SBIG model, only glimpsed as references in archived price sheets, but never observed in the wild... I did see an old expired ad for it at Scope City but they've been out of business for a while. I did say this would be an awesome camera, one that I'd be happy to own, so if I do come across this rainbow unicorn I will post it here. Thanks for letting me know!
I just wonder how bad the vignetting is with 1.25" filters on a 15 x 15 mm chip. SBIG says only this about the XCM: "Normally this size CCD is found in the STL camera body with 2" filters. However, because it is a special edition of the ST series, our standard 1.25" filter wheels are too small for this camera and we do not recommend 1.25" filters for this sized CCD."
You'll probably get some vignetting in the corners with 1.25" filters, especially if it's a fast telescope. The chip is 21 mm corner to corner.
Hilarious how the Universe works. A mono ST4K just came up on Astromart. BUT it was modded by SBIG: "This unit was serviced by SBIG and a KAI-4000 series Monochrome chip was installed. (The sticker on the unit still says ST-4000XCM)." So back to unicorns in Loch Ness for this story...
SBIG has a database, with serial numbers, detailing the Production Test results for all of the ST-4000XM manufactured between 2007 and 2012.
