2025-12-29 – Weekly Optician News : Edger PD accuracy debate

Last week, the forum was abuzz with discussions on equipment calibration challenges and reliable measurement tools. Members delved into the nuances of pupil distance accuracy, effective use of centration tools, and handling toric lenses. There was also significant interest in maintaining equipment without sacrificing productivity, alongside debates on lens quality and enhancing customer trust through precise measurements.


This Week’s Hot Topics

My edger thinks PD is a suggestion
A lively discussion emerged about the accuracy of edgers and the importance of precise pupil distance measurements, which are crucial for customer satisfaction and optical precision.
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Tools you trust for scleral sagittal height
Opticians shared their go-to tools for measuring scleral sagittal height, emphasizing the importance of reliable equipment in fitting specialty contact lenses.
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Centration tools that build trust
This thread focused on how using the right centration tools can enhance client trust and ensure better lens performance.
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Soft toric rotation quick-check
Members discussed efficient methods for checking the rotation of soft toric lenses, a key step in ensuring comfort and vision clarity for wearers.
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Keeping edgers clean without downtime
The community explored strategies for maintaining edgers to prevent downtime, balancing cleanliness with operational efficiency.
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Which lens has the highest Abbe value
A detailed examination of lens options with the highest Abbe values, helping opticians choose the best lenses for reducing chromatic aberration.
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Why your near PD is smaller
This thread clarified why near PD is typically smaller than distance PD, a crucial concept for multifocal lens fitting.
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Pupilometer stage fright at 2:15
Opticians shared experiences and tips for overcoming challenges with pupilometer readings, particularly when accuracy is critical.
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Best LED handheld magnifier for daily demos
A conversation about the best LED handheld magnifiers, highlighting those that enhance daily demonstrations and client interactions.
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Preventing AR crazing during frame heat
Tips and tricks were shared on avoiding anti-reflective coating damage during frame adjustments, a common concern for many opticians.
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Looking forward to another week filled with productive conversations and shared expertise. Have a great week ahead!

Anyone else notice the edger PD drift right after a wheel swap — . We started a 60‑second Monday check with a 64 mm calibration block and verify with a manual pupillometer before blocking; remakes dropped without killing productivity. @LabMike caveat: it only sticks if you swap out blocking pads regularly and re‑zero the tracer after cleaning.

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Quick example: we chased PD drift after wheel swaps until we added a ‘warm up 15 min’ step and a two‑point check with 64 and 68 mm blocks, plus a quick chuck/pad wipe — cut our variance by about 0.2 mm. @LensLab also had us log room temp; when HVAC swings, we slow the first pass or bump chuck pressure one notch, because my edger’s accuracy seems to follow the thermostat.

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Saw our numbers wander whenever the chuck pads glazed; swapping pads and dropping clamp force about 5% brought PD back in line. We do a 20‑second cut on a plano CR‑39 and verify against a 65 mm etched glass gauge (not toric) for centration — “no productivity hit,” just repeatable. If the room’s cool in the morning, @eclarke2020’s warmup helps, but pressure and pad condition were the real culprits for us.

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My fix was upstream at the blocker. > the room’s cool in the morning, @eclarke2020’s warmup helps, but pressure and pad condition were the real culprits Calibrating the blocker camera scale with a 66 mm bar and re‑zeroing parallax put us back at ±0.2 mm; small caveat — on high‑wraps, measure DBL manually or the math still lies.

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