Hotech SCA Field FlattenerThe HoTech SCA Field Flattener is fully multi-coated on two-element lens allowing the most efficient light transmission without sacrificing the precious collected light from your telescope. It accommodates f/5 to f/8 refractor telescope. You will see bright and sharp image across the entire field.
To capture great images from your telescope, it is essential to position your camera firmly in and on the optical axis of your drawtube/visual back. The SCA T-Adapter center loads your camera in the drawtube/visual back with a simple threading of a compression ring forcing the built-in rubber rings outward radially, thereby centering the camera in the drawtube/visual back for optimal installation.
All drawtube/visual back have manufacturing tolerances. And it requires larger diameter to accept various eyepieces and adapters. When the camera adapter is inserted, the gap between the drawtube/visual back and the inserting device became a slop problem. The rubber rings in the SCA expand radially according to users own adjustment to fill the gaps. This makes your camera seats firmly in your drawtube/visual back becoming part of your telescope for a secure and repeatable installation.
The optical axis is shifted when the inserting device is locked in by thumbscrew. In some cases, some poorly made unified compression ring can cause unstable tilt when locking in the drawtube due to loose tolerances between the compression ring, inner groove, and the uneven tip of the locking thumbscrew in a drawtube. The SCA T-Adapter adapts your camera without using the thumbscrew or the unified compression ring. (Note: Camera T-Ring not included.)
Small imperfections inside the drawtube like dents and scratches, the rubber rings fill the gaps and faithfully centers your camera in the tube. In addition, even if the drawtube is slightly deformed in diameter, egg-shape, the rubber rings in the SCA will compensate the differences and faithfully centers your camera.
Short profile design keeps the installed camera stable from low frequency oscillation transferred from the telescope in a windy environment. The back focus of a 2-inch SCA T-Adapter is 19 mm (0.75-inch) and 1.25-inch SCA T-Adapter is 18 mm (0.71-inch) measured from drawtube shoulder to the bottom T-Thread. The all-around adjustable tightness rubber contact damps unwanted vibrations from the telescope provides you a sturdy attachment on your telescope for a stable image capture.
SCA Field Flattener has built-in standard 2/48 mm (M48 x 0.75) filter thread. T-ring thread accepts all kinds of 35 mm cameras.
It is yet another dream come true for imagers!
HoTech Product Number: SCA-FFT58
Questions & AnswersAsk a Question
does it cover full frame dslr?
No, this flattener is only designed to cover APS-C format (28mm diagonal) or smaller cameras. Full frame coverage is difficult and often requires having the scope and flattener made by the same manufacturer for the express purpose of covering a full 35mm
I am imaging through an 8" RC f8 and the curvature is about 43% on my KAF-8300 and more on my APS-C sensor. Would this get rid of most or all of the curvature for my RC and is the camera side m42 or m48 with a t-ring adapter? Thank you!
According to David at HoTech, the SCA flattener will work well on the f/8 RC scopes. It will reduce the field curvature significantly for APS-C and 8300 size sensors. The camera side is T2 (M42x0.75) and the ideal back focus is 55mm behind the base of the
Would this work well on an Orion 6" RC f9 ?
Hello Jeff, Thank you for your question. It will correct the field curvature at the edge of the field of view of an RC but it will not correct for astigmatism. If you use a smaller sensor size (APS-C or smaller), you should not have an issue so in summar