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Equipment for the Serious Amateur Astronomer

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Part #7887
DG 0.85x Focal Reducer
 
Interface specifications:
  • A: M57P0.75 Male
  • B: M49.8P0.75 Male

Notes:

  1. Accomodates 52mm filter on the objective side.
  2. Distance from B-side interface flange to image plane: 55mm
  3. Works with 3rd party refractors such as:
    • Tak FC76, FC100, FS78 and FS102
    • Vixen ED80S, ED102S, FL80S and FL102S
  4. Sample configurations:
    • SLR Cameras: 7887 - [5001 to 5010] - [SLR Camera]
    • SBIG STL Series Cameras: 7887 - [M49.8-STL AD] - [STL Camera]
    • SBIG ST Series Cameras: 7887 - 7920 - 7522 - [CFW10/ST Camera]
    • Starlight Express SX Series Cameras: 7887 - 7920 - 7601 - 7601 - 7522 - [SX Camera]

The two included spacer rings adapt the reducer to specific Borg scopes as shown in the photos at right:

  • No spacer for 76ED/77ED or other scopes of about 500mm focal length
  • Thinner spacer : 100ED/101ED, 125SD, or other scopes of 600-650mm focal length
  • Thicker spacer : 125ED or other scopes of about 800mm focal length
Spacers may be installed by the user by unscrewing the front and rear lens assemblies of the reducer and inserting the required spacer.
 

  Uncropped, full frame, full resolution Sample Image (4.8MB):
  • Scope: Borg 101ED + 7887 DGL 0.85X focal reducer
  • Camera: Canon 5D
  • Exposure: 5 minutes (single frame) @ ISO 800
  • Corrections: No flat/dark frames applied
 
  Uncropped, full frame, full resolution Sample Image (1.8 MB):
  • Scope: Borg 101ED + 7887 DGL 0.85X focal reducer
  • Camera: SBIG STL-11000
  • Exposure: 16 x 6 min Lum, 8 x 6 min each RGB