Binorum Bahtinov Mask 100–140 mm
Sharp focus is essential in astrophotography. The Bahtinov mask makes achieving it fast, reliable, and straightforward. This plastic mask fits over the front of any telescope with an objective diameter between 100 and 140 mm. Its grid pattern lets you see at a glance whether the image is truly in focus.
How to use the Bahtinov mask
- Fit the mask over the front of your telescope.
- Point the telescope at a bright star.
- Switch your camera to live view mode and observe the star image on the screen.
- If focus is not yet correct, the central spike of the Bahtinov diffraction pattern will appear shifted relative to the two outer spikes.
- Adjust the focuser until the central spike sits exactly between the two outer spikes.
- At that point, focus for astrophotography is set precisely. Remove the mask and begin your exposure.
About Binorum
Binorum is a brand created by astronomers for astronomers. Every product is designed with a focus on build quality and practical performance under real observing conditions. The Binorum range of astronomy accessories covers focusing masks, filters, eyepieces, and mount accessories - all built to serve the observer reliably, night after night.
Key features
- Fits telescopes with an objective diameter of 100-140 mm
- Lightweight plastic construction - easy to fit and remove
- Grid pattern gives an immediate, clear focus indication
- Compatible with camera live view for precise astrophotography focusing
- No tools or adapters required
Specifications
| Parameter |
Value |
| Compatible objective diameter |
100-140 mm |
| Material |
Plastic |
| Fitting method |
Slip-on over telescope front |
| Intended use |
Astrophotography focusing |
| Brand |
Binorum |
