Explore Scientific 3" .7x Focal Reducer & Field Flattener for APO Refractors
The Explore Scientific 3” Focal Reducer and Field Flattener is a versatile accessory made to augment your astrophotography adventure. As a field flattener, this accessory will take care of annoying edge-of-field aberrations brought about by curved focal planes, resulting in clear, sharp images. As a focal reducer, this accessory will reduce your focal ratio by 0.7 for a wider field of view and increased image illumination in shorter exposure intervals.
Explore Scientific recommended this accessory for their 127mm and 152mm APO refractors. Features fully multi-coated optics and comes with a 3" Nosepiece, 2 adapters for various focuser sizes and a male T-thread adapter for the camera.
Explore Scientific Product Number: FFFR507X-00
- Additional Information
SKU ES-FFFR507X-00 UPC Code 812257014408 Manufacturer Explore Scientific Barrel Size 3" Warranty Lifetime Warranty
- Included Items
- 3" .7x Focal Reducer & Field Flattener
- 3" Nosepiece Adapter
- 2 adapters for various focusers
- T-Thread Adapter
- Questions & Answers
Product QuestionsIs the standard focuser that comes with the ES 127mm capable to handle the weight of the reducer +DSLR camera? it seems a bit heavy for itWhat's the reducer field stop? Would this reducer work on the 16" Meade ACF F8 with a 36.7 × 36.7 mm KAF-9000 CCD chip+OAG?Question by: Pere on Jan 8, 2017 3:37:00 PMThe manufacturer does not state what the reducer's field stop is, but given that it comes with a standard T2 adapter, the clear aperture as intended by the manufacturer comes out to ~40mm. If you remove the T2 adapter, you get more clear aperture, but it is doubtful that this optic is designed to correct a sensor larger than 35mm format.
This will not work properly on an 16" Meade ACF (totally different radii of curvature compared to the ES152 Apo, and over-correction of coma), and it will not correct (though it will probably illuminate) a 52mm image circle.Answer by: Chris Hendren on Jan 10, 2017 8:59:00 AMQuestion by: Hemi Patel on Mar 21, 2016 6:00:00 AMAs long as you have the newest version of the ES-102 CF Triplet where the 2" adapter on the focuser unthreads, this reducer can be used. Because you only have 2" of throughput on the focuser drawtube, you may see some vignetting with larger sensors, but anything up to APS-C should be fine.Answer by: Chris Hendren (Admin) on Mar 21, 2016 6:04:00 PMQuestion by: J Price on Mar 27, 2016 6:19:00 AMUnfortunately, no. The back focus from the reducer to the focal plane is too short for even a 1.25" diaginal and eyepiece. This is a purely photographic accessory. For visual use, a 2" diagonal and 30mm-56mm wide eyepiece would be the best solution.Answer by: Chris Hendren on Mar 28, 2016 10:36:00 AM
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