As a QHY dealer we do have access to all QHY cameras and when the design solution for such a "seemingly impossible product" like the FCCT I came up, we were able to use QHY cameras for all tests concerning RASA and FCCT adaptation and find out about all obstacles (there were many, one of them being the fact that not two RASA 8s have the exact same image plane position...). So for this combination we know that it works and we did add two 0.5 mm shims to enable the user to compensate for such fine focal differences. Now any 77mm diameter QHY-camera body featuring the 6.5 mm chip distance can be mounted onto the Baader FCCT I – suitable for Ø 77 mm QHY-Cameras (e.g. QHY 174 / 163 / 183) and onto RASA 8 optics with three screws (check the instruction manual ).
However, we did integrate the four-hole-scheme of the smaller ZWO ASI cameras into the FCCT I camera flange, but there is no detailed instruction manual available for this and we had no opportunity to test the FCCT I ourselves with ASI cameras. Some mechanically skilled customers already managed to mount an ASI onto an FCCT I by locating the necessary longer screws themselves and did successful imaging with their RASA 8 (see test review). However, we would not recommend this for everyone, since the FCCT is not a simple "consumer-product" but was intended for hardnecked "Amateurs" – which by definition are "lovers, devoted to a cause".
So if you have a 78mm diameter ZWO camera and want to fit an FCCT I, maybe contact your local dealer and see if he can offer you an FCCT I with the option of taking it back if it doesn't fit your ZWO-camera after all.
The Baader FCCT II for RASA 8" – for Ø 90 mm QHY cameras (e.g. QHY 268M/C / 294 / 533) is not suitable for the ASI camera series. While the outer body and the mounting holes would fit w/o a problem, unfortunately the optical backfocuss of the available ASI models, from the mounting surface to the Chip, is 17.5. Even when removing the black adjustable adaptation plate, the resulting Backfocuss of then 12.5mm is still 5.5 mm more then the one from QHY QHY268M in the shortest possible adaptation.
With the typical Backfocuss of a RASA8 beeing only very limited, unfortunately those 8mm can not be gained in the mechanical adaptation. Die einzige Möglichkeit, den FCCT II an ASI-Kameras mit 90 mm Durchmesser und 17,5 mm Backfocus anzupassen, wäre eine tiefgreifende Modifikation: Das Entfernen das Loch des oberen Sensordeckels und das Kamerafenster zu entfernen sowie eine mechanische Neugestaltung, um die äußere Form der QHY268M anzugleichen, um eine kürzere Anpassung zu erreichen. Da dies die Garantie erlöschen lässt und die staubfreie Umgebung der Sensorkammer jeder ASI-Kamera beeinträchtigt, halten wir diesen Ansatz nicht für sinnvoll.
The only possible way, to adapt the FCCT II to ASI Cameras with 90mm diameter and 17.5mm Backfocuss would be to remove the hole upper Sensor Cover enclosure and Camera Window and rebuild it with our own mechanics and resemble the QHY268 outer shape to reach a shorter adaptation. Since this would voide the warranty and destroy the clean environment of the sensor chamber, of every individual ASI Camera we don’t think that making such a product is worth while
And for the larger RASAs this restriction also does not apply, since there the longer backfocus does allow to mount any camera when combining the UFC-filter chamber and the UFC-tilter
