Description
Help control dew, reduce stray light, and check your focus.
The Starfield Optics Dew Shield and Bahtinov Focus Mask combine two practical accessories for the ZWO Seestar S50 smart telescope. The 3D printed dew shield helps delay condensation on the front lens and block unwanted off-axis light, while the removable focus mask provides a visual reference for checking focus on a bright star.
Use the mask to assess focus before imaging, then remove it and leave the dew shield in place during your observing session. The mask’s built-in handling tab makes it easy to grasp during installation and removal.
Key Features
- Designed for the ZWO Seestar S50: A dedicated dew shield and focus mask combination.
- Passive dew protection: Helps delay condensation without additional power or cables.
- Stray-light shielding: Helps block off-axis light from nearby streetlights, porch lights, and other sources.
- Removable Bahtinov focus mask: Produces a diffraction pattern around a bright star to help assess focus.
- Convenient handling tab: Makes the mask easy to grasp and remove.
- Black 3D printed construction: A practical addition to your Seestar accessory kit.
How to Use the Bahtinov Focus Mask
- Attach the dew shield to your Seestar S50.
- Place the Bahtinov mask over the front of the dew shield.
- Point the telescope at a bright star and inspect the diffraction pattern in the live view.
- If needed, adjust focus manually until the central diffraction spike is centred between the other two.
- Remove the focus mask before capturing images. Leave the dew shield in place during your imaging session.
Frequently Asked Questions
What does a dew shield do for the Seestar S50?
A dew shield helps delay condensation by limiting the front lens’s exposure to the open sky. It also helps block unwanted light entering from outside the telescope’s field of view.
What is the Bahtinov focus mask used for?
The mask creates diffraction spikes around a bright star. When the central spike is centred between the other two, it indicates good focus. It provides a visual way to check focus and guide manual adjustments.
Do I leave the focus mask attached while imaging?
No. Remove the Bahtinov mask after checking focus and before capturing your images. The dew shield remains in place during imaging.
Will the dew shield completely prevent condensation?
It helps delay dew formation, but condensation can still occur in humid conditions. Active dew heating may still be needed.
Does this version fit the Seestar S30 or S30 Pro?
This version is designed for the ZWO Seestar S50. Choose the separate S30 / S30 Pro dew shield for those models.
What is included?
One Starfield Optics dew shield and one removable Bahtinov focus mask. Telescope not included.
Product Finish
Visible print layers and minor surface variations are normal for 3D printed products.