Adapter to attach QSI's 500 Series WSG Cameras to Astro-Physics 2.7" and 4" Prime Focus Field Flatteners (A3512-A)

This adapter is specifically designed to attach AP 2.7" and 4" Field Flatteners to QSI’s 500 and 600 series WSG medium format cameras and to maintain the critical spacing to the focal plane at the perfect 86.4 mm. It utilizes the larger QSI and SBIG STL 2.156" thread size in order to minimize vignetting when using fast focal ratio telescopes. (2" nosepieces and T-threads are often too restrictive for today’s larger sized detector chips when used with fast scopes.)

The versatility of this adapter takes a quantum leap forward when paired with the 2.7" to 6 x 7 Outer Bayonet Adapter (ADA2767):

• With the A3512 and the ADA2767 together, the QSI camera can be rigidly attached to many Meade and Celestron SCTs using either the Meade adapter (ADASCTLM27) or the Celestron adapter (ADASCTLC27).
• It can also be attached to the Photographic-Visual Telecompressor (27TVPH) with an added 1.25" extension tube (A3504-A) to produce the proper 0.75x compression. Of course, extensions of other lengths can be used to achieve different compression ratios.
• When using the 2.7" extension with internal T-thread (A3511) with the BARADV or the Baader FFC Barlow (BPFFC), it can be attached to several combinations of extension tubes, thus achieving various magnifications for lunar or planetary imaging.
• If not using a Prime Focus Field Flattener, it can be joined to the ADA2767 and attached to the standard 2.5" long extension tube (A1008-A) for direct use with the AP 2.7" focuser drawtube.

All the above options provide greater rigidity and less flexure than using a 2" nosepiece and its associated combinations.

This adapter has a net spacing distance of 1.33" (33.73 mm).