This telescope is checked, measured and adjusted if necessary before delivery. The focuser is set. Upon request, you will receive a meaningful quality certificate from your telescope (test report with star test, Ronchi, adjustment, with individual serial number) included! Please specify with order!
Examples of our test protocols: test recordings
How we adjust: About us

 William Optics Apochromatic Refractor AP 71/420 Gran Turismo GT 71 OTA

The Gran Turismo refractor is an apochromatic triplet with FPL-53 element for the highest color purity and strong contrast! A lens telescope that is versatile and leaves little to be desired.

Visual observation: Equipped with an optional zenith mirror, you can use this apo to observe the moon and planets with the highest possible contrast. The bright apo also allows persistent observation of difficult DeepSky objects: star clusters, galaxies and nebulae. Due to the crisp sharp star image, the observation and dissolution of globular clusters is a great pleasure.
For astrophotography we recommend the flat field flattener and focal length reducer (Flattener / Reducer) Flat6AIII from William Optics. The optics also provide a flat field with the same focus for full-frame cameras. Via the prism rail holder integrated in the handle, you can equip your Gran Turismo with a guiding scope that can be used as a viewfinder or guide scope.
The stocked 2.5 "R&P focuser has a long focusing path, a reduction and a temperature display. The scope of delivery also includes an adapter for 1.25" eyepieces.




The very robust Gran Turismo Apo is really very suitable for travel and for mobile astronomy and astrophotography at all. Take the Apo with you under a dark sky and discover the best objects from the Messier and NGC catalog. The telescope is uncomplicated, stable to adjust and, after the Firstlight, your new favorite telescope!

Another special feature of the new William Optics apochromats is the specially calculated focus mask according to Bahtinov:



These new focus masks made of optical acrylic glass offer 92% light transmission.

The embossed pattern provides an approximately three times lighter diffraction structure than the classic metal masks. The mask made of acrylic glass thus shows a clearer diffraction pattern and allows focusing with the help of fainter stars.


Technical specifications:

optics
type refractor
Type Apochromat Triplet
Opening (mm) 71
Focal length (mm) 420
Opening ratio (f /) 5.9
Resolving power (arc seconds) 1.94
Limit size (mag) 11.1
Light collecting capacity (-fold a 7mm pupil) 100
Max. Sensible enlargement (-fold) 142
Tube weight (kg) 2.2
Tube diameter (mm) 82
Dew cap diameter (mm) 92
Transport length (mm) 325
Tube length (mm) 427
Compensation SMC multi-shift compensation
Lens hoods in the tube yes
Okularauszug
Type rack
Connection (eyepiece side) (inch) 2
Free opening (mm) 64
Ring clamp yes
Reduction 1:10 fine drive
mount
type OTA
Mount type without mount
Included accessories
Finderscope no
Taukappe yes
no deflecting
Eyepiece adapter 1.25 "- 2"
Dovetail Vixen Style
Other Bahtinov focus mask
Handle yes
Transport bag yes
Generally
Gran Turismo series
application areas
Astrophotography yes (very good)
Moon & planets yes
Nature observation no
Nebulae & galaxies yes
Sun no (only with a suitable sun filter)
Recommended for ...
beginners no
advanced yes
Observatories no