This is one of the best times to be an amateur astronomer due the vast expansion of affordable equipment available to those interested in this hobby!  Just a few years ago ANY CCD (or CMOS) camera worth using was well over $4,000; today, you can purchase a much higher quality imager with a color filter wheel for around $3,000 or less! 

My camera of choice to match the capability of my TEC 140mm refractor is the ZWO2600MM DUO.   In the past CMOS chips could not offer the quality of a CCD.  Advancements in CMOS technology and a back illuminated sensor has advanced the CMOS as a cooler, smoother and improved SNR. The ZWO2600mm DUO is self guided with a 2.1MP sensor.  To accomodate the large main sensor and guide chip the 2" EFW is required. The camera uses the telescope as a lens and it can only create color images by combining images taken through Luminance (Clear), Red, Green and Blue filters.  My filter wheel also contains Hydrogen Alpha (for imaging nebulae) , Oxygen III filter (500.7 and 495.9nm) and Sodium II (around 672-673nm).  

        The filter wheel that attaches to the ZWO2600MM DUO as mentioned before can only be the 2" EFW.  That being said, quality 50.4mm filters are expensive.  The Baader LRGB set I bought ran around $900.  The Baader HA, OIII and SII filters were slightly over $1,000.  I chose Baader filters due to my interaction with Johannes Baader at NEAF 2025 where he explained their new CMOS optimized filters, their reputation, comparison with other filters such as the series of 2" Chroma at a much higher price (with subtle differences in comparitive) results.   The filters which came with a hefty price tag but are worth every penny!

I had previous used 36mm Astrodon Gen II LRGB and HA filters and I'm keeping those for the smaller 65mm Astrograph which will piggyback on my TEC 140!

    My advice?  Yes, SBIG cameras and the accessories to create impressive images can be expensive, but not so much so that you should deprive yourself of the quality these cameras offer.  Consider this; SBIG cameras have electromechanical shutters, do not have column defects, frequently have self-guiding chips within the camera (no need for an additional camera to guide), very low thermal noise, wide field images, an electric cooling fan and the ability achieve -50ºC cooling resulting in a superior quality camera. 

Think about this: Take a look at Astronomy or Sky & Telescope magazines and notice that the images in the reader pictures section are frequently taken with SBIG cameras.  It's not popularity or prevalence that makes SBIG cameras number one for amateur photos in astronomy magazines, its quality of the cameras and images plain and simple.