Phone: (256) 723-8381

Imaging Dall Kirkham Astrograph

"I guess you can tell I am quite happy with the [iDK] scope and highly recommend them.  I have to thank Dave for the effort of design and build of my new iDK.  I don't ever intend to sell it."  Gerald Miller - OK, USA

AG Optical Systems Imaging Dall Kirkham (iDK) astrographs are high resolution instruments with outstanding on and off axis performance across a huge 60mm field of view. By combining large aperture, medium focal ratio, corrected optics in a lightweight, stiff, and thermally stable carbon fiber tube AG Optical Systems has created a 100% made-in-the USA instrument capable of capturing stunning images of our universe.  When only the best will do, contact AG Optical Systems to experience the quality, innovation, and performance that goes into everything we make. 

Can your telescope produce this type of image?   If not call AG Optical Systems!     Telescope specs are listed below.

M81 by Dan Wilson, AG Optical Systems 17" iDK 

M81 by Dan Wilson, AG Optical Systems 17" Imaging Dall Kirkham 

Now available with Optec's new Gemini rotating focuser with temperature compensation! 

An optional quartz upgrade is now available for all iDK telescopes.  Quartz' extremely low coefficient of thermal expansion allows the figure on the optics to remain stable while ambient temperatures vary.  This means you will spend more time imaging and less time waiting for the optics to stabilize. 


Imaging Dall Kirkham Astrograph Features
  • High-performance optics figured and quality tested as a system by Ostahowski Optics. Optional quartz upgrade for the ultimate in optical stability as ambient temperatures vary.
  • Fast F6.7 system designed and baffled to cover 50mm and larger size chips. Click here to see CCD Inspector analysis of a 17" iDK over a 43' x 29' field of view.
  • Over 6.25" of back focus to support almost any combination of imaging components
  • Excellent coma free, astigmatism free, flat field performance over 60 mm image circle. Ckick here and here to see the performance of a 12.5" iDK using a camera with a 2" diagonal chip (36mm x 36mm array, 52mm diagonal).
  • RMS spot diameter* less than 9 microns across 60 mm image circle from .380 to 1 microns (we state RMS spot size in diameter rather than radius as do other manufacturers)

             * Spot diagrams:  10" iDK12.5" iDK14.5" iDK17" iDK, 20" iDK

  • Highly robust, precise Optec TCF-S3i focuser is standard. Optional FLI Atlas focuser.  Optec Gemini rotating focuser upgrade option.  
  • High reflectivity 96% coatings produced in Ostahowski Optics' state-of-the-art coating chamber
  • Outstanding field illumination across big chip cameras. Click here to see an unprocessed iDK image taken by a 16803 CCD camera that has not been flat fielded.
  • Carbon fiber truss tube engineered to provide rigidity and thermal stability.
  • CNC machined components with stainless steel fasteners
  • Best  in class customer support and pricing


System Specifications                                                                          

Model iDK10 iDK12.5  iDK14.5  iDK17 iDK20
Aperture 10 12.5 14.5 17" 20"
Focal ratio 6.7 6.7 6.7 6.7 6.7
Focal length 67" 83.5" 97.2" 114" 134"
Back focus (at mid travel of focuser) 6.5" with Optec TCF 6.5" with Optec TCF
6.5" with Optec TCF
6.25" with Optec TCF
6.25" with Optec TCF
OTA type CF Tube CF Truss CF Truss CF Truss CF Truss
Primary and secondary mirrors  Supremax 33 substrate.  Optional quartz upgrade. 
Fans (blowing air into OTA) 3 x 60mm fans  3 x 60mm fans    3 x 60mm fans 3 x 80 mm fans 4 x 80 mm fans
Secondary obstruction 5.6" 6.7" 7.5" 8.2" 9"
Focuser (included) Standard: Optec TCF-S3i 3" temperature compensating digital focuser
Corrector Two element,
<.5% reflection broadband AR coated on every lens surface
Mirror Coatings 96% Enhanced
Aluminum, coated by Ostahowski Optics
Baffling primary and secondary baffles, baffled for 2" diagonal size chip
Dovetail Heavy-duty, Losmandy "D" compatible dovetail plate included
Tube length 24.4" 30" 36" 42" 47"
Dimensions Here Here   Here  
OTA Weight approx. 26 lbs approx. 44 lbs approx. 54 lbs approx. 102 lbs approx. 141 lbs
OTA weight with dovetail &  focuser approx. 30 lbs approx. 52 lbs approx. 58 lbs approx. 110 lbs approx. 150 lbs
Price $8,995 $10,995 $14,975 $20,995 $29,995
Quartz upgrade (both mirrors) $1150 $1550 $2475 $3750 $6500
Optec Gemini rotating focuser upgrade $1495 $1495 $1495 $1495 $1495
AGO Thermal Control System $975 $975 $975 $975 $975
Shroud n/a $125 $135 $140 $165
Piggyback Dovetail Plate $185 $225 $245 $265 $305
Crating $200 $250 $275 $375 $475
Spacers & Adapters Contact AG Optical Systems
Delivery Contact AG Optical Systems
Shipping Contact AG Optical Systems

12.5" iDK Truss Astrograph

Solidworks CAD model of 12.5" Imaging Dall Kirkham astrograph

IC410 by Tim Khan, AG Optical Systems 12.5" iDK, 16803 2" diagonal CCD chip 

AG Optical Systems 12.5" Imaging Dall Kirkham secondary spider assembly

AG Optical Systems 12.5" Imaging Dall Kirkham Truss Structure

AG Optical Systems Thermal Control System

M81 by Dan Wilson, AG Optical Systems 17" iDK, SBIG STLX camera

NGC6960 by Mike Miller, AG Optical Systems 12.5" Imaging Dall Kirkham, Apogee camera