focusing aid

We sell Bahtinov Mask, Tri-Bahtinov Mask, Carey mask and Hartmann mask. The product can be customized

according to your needs.

tri-bahtinov mask

If you are interested in collimation, you may consider the tri-bahtinov mask.

A Tri-Bahtinov Mask for Aiding Collimation and Focusing of Schmidt Cassegrain, Ritchey-Chretien, and Newtonian Telescopes.

Bahtinov Mask

Example diffraction patterns produced by a Bahtinov mask

(middle: in focus, left and right: slightly out of focus)

The Bahtinov mask is a device used to focus small astronomical telescopes accurately. Although masks have long been used as focusing aids, the distinctive pattern was invented by Russian amateur astrophotographer Pavel Bahtinov in 2005. Precise focusing of telescopes and astrographs is critical to performing astrophotography.

The telescope is pointed at a bright star, and a mask is placed in front of the telescope's objective (or in front of the aperture).



Bahtinov mask

Simulation of the Bahtinov mask diffraction pattern, using "Maskulator". Each frame shows a focus difference of 140.6 μm.

Size > Cost

55-70 millimeter Diameter > INR 700

65-80 millimeter Diameter > INR 700

80-95 millimeter Diameter > INR 750

95-110 millimeter Diameter > INR 800

100-115 millimeter Diameter > INR 850

115-130 millimeter Diameter > INR 900

130-145 millimeter Diameter > INR 950

145-160 millimeter Diameter > INR 1000

160-175 millimeter Diameter > INR 1100

175-190 millimeter Diameter > INR 1200

190-205 millimeter Diameter > INR 1300

205-220 millimeter Diameter > INR 1400

220-235 millimeter Diameter > INR 1500

235-250 millimeter Diameter > INR 1600

250-265 millimeter Diameter > INR 1700

265-280 millimeter Diameter > INR 1800

280-295 millimeter Diameter > INR 1900

520-580 millimeter Diameter > INR 3500