This adjustable 1.0X field flattener from Starfield Optics is designed to work with 70 mm to 155 mm Starfield telescopes with a 63mm (2.5") focuser.  The camera side of the flattener has 48mm threads and will accept a 2" filter.

Please Note:  This flattener will work with Gen II of the G115 Gear Triplet by using the 2.5" adapter that is included with the telescope.  Of course, the flattener also works with the original G115 since that version comes with a 2.5" focuser, just like so many Starfield refractors do.

The Starfield 1.0x adjustable flattener makes finding the correct back focus easy! Fighting with adapters is a thing of the past!

By setting the adjustment required for your telescope, achieving the correct amount of back focus is simple. If more adjustment is needed for fine tuning all that is needed is a small twist. If you are using accessories such as filter wheels and rotators you can not still get the required back focus, just add up the thickness of all the accessories, plus the distance to your sensor and subtract from 69.87 and then set the reducer to the number that is calculated.

The reducer attaches directly to the Starfield telescope focusers. Using the supplied 1.5mm Allen key, loosen off the three screws a half turn and then unscrew the lock, then thread the reducer onto the focuser.

This 1X Flattener is designed for telescopes ranging from 80mm to 155mm.  

• 80 mm / focal ratio f/6 - 81.2 mm
• 90mm / focal ratio f/6 - 82.5mm
• 102 mm / focal ratio f/7 - 75.3 mm
• 115 mm / focal ratio f/7 - 73.0 mm
• 130 mm / focal ratio f/7 - 69.7 mm
• 140 mm / focal ratio f/6.5 - 68.0 mm
• 155 mm / focal ratio f/8 - 57.0 mm