TI 55  WPF f/2.6 Astrograph – OPTICAL PERFORMANCES

Telescopi Italiani has decided to show a full review about the awesome optical performances of our TI 55  f/2.6 Astrograph

No other manufacturer shows detailed diagrams like these.

SPOT DIAGRAM

The Spot Diagram and the other performance diagrams, was calculated:

• On Axis (1)
• 11.6 mm from axis – corner of the KAF8300 (2)
• 17.29 mm from axis – corner of the KAF16200 (3)
• 26.10 mm from axis – corner of the KAF16803 (4)
• 30.65 mm from axis – corner of the KAF39000/KAF50100 (5)

TI 55 WPF f/2.6 Super Fast Astrograph (550 mm aperture- 1445 mm focal length): IT IS REPRESENTED THE SPOT DIAGRAM CONSIDERING THE WAVELENGHT FROM 400 TO 700 nm.

 TI 55 f/2.6 – Spot Diagram

THE GRAPH BELOW SHOWS A  SPOT DIAGRAM vs FIELD UP TO 30 MM OFF-AXIS (59 MM REAL DIFFRACTION LIMITED CORRECTED FIELD – Despite the extremely fast f/2.6 ratio)

If you want to compare our performance with respect others Wynne corrector prime focus astrographs, probably you need a Matrix Spot Diagram with 40 micron scale bar – still consider here we are @ f/2.6 –:

SPOT DIAGRAM vs WAVELENGTH

A very important diagram that nobody shows. Only after analyzing these curves we can see that the optic is really excellent for every wavelengths. The black line is the Airy Disc radius, the numbers are the five fields.

RELATIVE ILLUMINATION

The Relative Illumination curve is the ratio between  the light hitting the focal plane and the total light  incoming. To obtain a good illumination for so fast f/2.6 astrograph was been necessary to increase significally the Wynne corrector lenses diameter up to reach 164 mm (6,5 inch) diameter. Even more considering the huge backfocus of 82 mm from the corrector flange very useful.

Thanks to the Prime Focus configuration, this super fast Astrograph, has an awesome amount of collected light – due to the relatively small obstruction of 37,3% – up to 86.5 % of usable light.

TI55 f/2.6 Vignetting Diagram[/caption]