Takahashi Announces a New Flattener for the FSQ-85EDX

Takahashi has released a new flattener for use with the FSQ-85EDX telescope that provides a flat field like that of the FSQ-106EDX4 for full frame DSLR and CCD cameras. This flattener is available for pre-order, with expected delivery in late November 2017.

Takahashi has released a new flattener for use with the FSQ-85EDX telescope that provides a flat field like that of the FSQ-106EDX4 for full frame DSLR and CCD cameras.  This flattener is available for pre-order, with expected delivery in late November 2017.

When originally conceived, the FSQ-85EDX was meant for use with APS-C or smaller CCD or CMOS chips.  At an image circle radius beyond about 14 mm, field curvature could become evident in larger chips.  This new flattener will greatly reduce this field curvature, resulting in a practically flat field out to a 22mm image circle radius. The two spot diagrams below demonstrate the impact of the flattener on field curvature:

Spot Diagram of FSQ-85EDX Without Flattener

Spot Diagram of FSQ-85EDX With Flattener

An updated system chart incorporating the new flattener can be found here.  Below are other technical details of the new flattener.

Description:                             Flattener 1.01X for FSQ-85EDX

SKU:                                       TKA37582

Effective Focal Length:              455 mm (f/5.4)

Image Circle Diameter:             44 mm

Metal Back:                              56 mm

Weight:                                    200 g