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Dew-Not

Dew-Not

Dew-Not heater strips take a different approach to dew prevention: a flat resistive element distributed across the whole strap rather than a coiled wire, which spreads heat evenly instead of creating hot lines. Even, gentle heating is exactly what you want, because localized heat creates the tube currents that soften an image. David Astro carries Dew-Not products in Canada, held in stock for fast domestic shipping.

Strap length is matched to your optic's circumference. Tell us your telescope, finder and guide scope and we will list the sizes you need.

Filters

CA$39.00 - CA$39.00
CA$39.00
CA$39.00 - CA$39.00
CA$39.00

Dew-Not Heater Strip - .965" Eyepiece

DN001
1 in stock

The Dew-Not Dew Heaters are an essential accessory for every astronomy enthusiast aiming to enhance their stargazing experience. These dew heaters...

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CA$39.00 - CA$39.00
CA$39.00
CA$39.00 - CA$39.00
CA$39.00
CA$87.00 - CA$87.00
CA$87.00
CA$87.00 - CA$87.00
CA$87.00

Dew-Not Heater Strip - 10" Scope

DN011

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$87.00 - CA$87.00
CA$87.00
CA$87.00 - CA$87.00
CA$87.00
CA$91.00 - CA$91.00
CA$91.00
CA$91.00 - CA$91.00
CA$91.00

Dew-Not Heater Strip - 11" Scope

DN012
2 in stock

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$91.00 - CA$91.00
CA$91.00
CA$91.00 - CA$91.00
CA$91.00
CA$95.00 - CA$95.00
CA$95.00
CA$95.00 - CA$95.00
CA$95.00

Dew-Not Heater Strip - 12" Scope

DN013
1 in stock

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$95.00 - CA$95.00
CA$95.00
CA$95.00 - CA$95.00
CA$95.00
CA$98.00 - CA$98.00
CA$98.00
CA$98.00 - CA$98.00
CA$98.00

Dew-Not Heater Strip - 14" Scope

DN014
2 in stock

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$98.00 - CA$98.00
CA$98.00
CA$98.00 - CA$98.00
CA$98.00
CA$108.00 - CA$108.00
CA$108.00
CA$108.00 - CA$108.00
CA$108.00

Dew-Not Heater Strip - 16" Scope

DN015

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$108.00 - CA$108.00
CA$108.00
CA$108.00 - CA$108.00
CA$108.00
CA$48.00 - CA$48.00
CA$48.00
CA$48.00 - CA$48.00
CA$48.00

Dew-Not Heater Strip - 3" Scope

DN004

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$48.00 - CA$48.00
CA$48.00
CA$48.00 - CA$48.00
CA$48.00
CA$42.00 - CA$42.00
CA$42.00
CA$42.00 - CA$42.00
CA$42.00

Dew-Not Heater Strip - 32mm Guide Scope or 1.25" Eyepiece

DN002
4 in stock

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$42.00 - CA$42.00
CA$42.00
CA$42.00 - CA$42.00
CA$42.00
CA$56.00 - CA$56.00
CA$56.00
CA$56.00 - CA$56.00
CA$56.00

Dew-Not Heater Strip - 4" Scope

DN005

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$56.00 - CA$56.00
CA$56.00
CA$56.00 - CA$56.00
CA$56.00
CA$62.00 - CA$62.00
CA$62.00
CA$62.00 - CA$62.00
CA$62.00

Dew-Not Heater Strip - 5" Scope

DN006

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$62.00 - CA$62.00
CA$62.00
CA$62.00 - CA$62.00
CA$62.00
CA$43.00 - CA$43.00
CA$43.00
CA$43.00 - CA$43.00
CA$43.00

Dew-Not Heater Strip - 50mm Guide Scope or 2" Eyepiece

DN003
6 in stock

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$43.00 - CA$43.00
CA$43.00
CA$43.00 - CA$43.00
CA$43.00
CA$67.00 - CA$67.00
CA$67.00
CA$67.00 - CA$67.00
CA$67.00

Dew-Not Heater Strip - 6" Scope

DN007
3 in stock

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$67.00 - CA$67.00
CA$67.00
CA$67.00 - CA$67.00
CA$67.00
CA$71.00 - CA$71.00
CA$71.00
CA$71.00 - CA$71.00
CA$71.00

Dew-Not Heater Strip - 7" Scope

DN008
4 in stock

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$71.00 - CA$71.00
CA$71.00
CA$71.00 - CA$71.00
CA$71.00
CA$77.00 - CA$77.00
CA$77.00
CA$77.00 - CA$77.00
CA$77.00

Dew-Not Heater Strip - 8" Scope

DN009

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$77.00 - CA$77.00
CA$77.00
CA$77.00 - CA$77.00
CA$77.00
CA$83.00 - CA$83.00
CA$83.00
CA$83.00 - CA$83.00
CA$83.00

Dew-Not Heater Strip - 9" Scope

DN010
5 in stock

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$83.00 - CA$83.00
CA$83.00
CA$83.00 - CA$83.00
CA$83.00
CA$95.00 - CA$95.00
CA$95.00
CA$95.00 - CA$95.00
CA$95.00

Dew-Not Heater Strip - Binoviewer

DN017
2 in stock

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$95.00 - CA$95.00
CA$95.00
CA$95.00 - CA$95.00
CA$95.00
CA$83.00 - CA$83.00
CA$83.00
CA$83.00 - CA$83.00
CA$83.00

Dew-Not Heater Strip - Hand Controller

DN016
5 in stock

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$83.00 - CA$83.00
CA$83.00
CA$83.00 - CA$83.00
CA$83.00
CA$45.00 - CA$45.00
CA$45.00
CA$45.00 - CA$45.00
CA$45.00

Dew-Not Heater Strip - Rigel Quick Fix

DNRQ

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$45.00 - CA$45.00
CA$45.00
CA$45.00 - CA$45.00
CA$45.00
CA$60.00 - CA$60.00
CA$60.00
CA$60.00 - CA$60.00
CA$60.00

Dew-Not Heater Strip - Telrad Heated Shield

DN018
4 in stock

Dew-Not™ has been involved in the design and manufacture of resistive heating elements for over 30 years. Their dew heater strips uses a thick film...

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CA$60.00 - CA$60.00
CA$60.00
CA$60.00 - CA$60.00
CA$60.00

Even Heating and Why It Matters

A dew heater has to raise the glass a few degrees above the dew point without creating a temperature gradient inside the tube.

  • Flat distributed elements: Heat spread across the strap's whole area rather than concentrated along a wire, which reduces localized hot spots.
  • Length matched to circumference: The strap should encircle the tube near the objective or corrector without excessive overlap, which wastes power.
  • Sizes across the whole rig: Straps for main optics, guide scopes, finders and eyepieces, since each dews independently and often the small ones go first.
  • Standard connectors: RCA connections compatible with common dew controllers, so the straps integrate with whatever controller you use.
  • Controller pairing: Designed to be run through a pulse-width controller rather than at full power, which cuts consumption substantially.
  • Cold-weather durability: Construction intended to remain flexible and intact through repeated freeze cycles.

Why Choose David Astro for Dew-Not

Heater selection is a sizing exercise and a power budgeting exercise, and both are quick to do properly.

  • Sized to actual circumference: We calculate strap length from your tube's outer diameter including a dew shield if the strap sits over it.
  • Whole-rig coverage: We count every optic that dews — main scope, guide scope, finder — so you are not adding straps one at a time across a season.
  • Power totalled: We add the full set's draw to your other loads so your battery lasts the night.
  • Authorized dealer: Genuine products with manufacturer warranty, in Canadian stock.
  • Ships from Canada: No duties or brokerage fees for Canadian orders.

Dew-Not in Canada — Frequently Asked Questions

Why does even heating matter?
Concentrated heat creates convection currents inside the tube that blur detail. A strap that distributes heat evenly at low power keeps the optic clear without degrading the view.
What length strap do I need?
Enough to encircle the tube at the point where it will sit, with a small overlap. Measure the outer diameter and multiply by pi, or tell us the telescope model and we will size it.
Do I need a controller?
Strongly recommended. Running straps at full power wastes battery and risks tube currents. A pulse-width controller holds the optic just above dew point and cuts consumption considerably.
Can I use these on a corrector plate?
Yes, and Schmidt-Cassegrains particularly need them since the corrector sits exposed at the front. Place the strap on the tube just behind the corrector cell.

Sizing heater straps?

Tell us every optic on your rig and we will list the sizes and total the power. Canadian stock, worldwide shipping.