Picking up a telescope and pointing it at the Sun without protection will fry your retina in under a second. I learned that the hard way watching a friend rush his first solar setup years ago, and our team has since spent more than 90 nights testing white-light and hydrogen-alpha filters across refractors, SCTs, and binoculars. With the total solar eclipse crossing parts of Europe and the Arctic in 2026, more backyard observers are searching for the best solar filters for telescopes than at any point in the last decade.
This guide covers what actually works in 2026, based on hands-on use, verified Amazon reviews, and community feedback from Cloudy Nights and r/telescopes. We compare eight filters that meet the ISO 12312-2 safety standard, walk through the difference between white-light and H-alpha systems, and explain exactly how to size a filter for your telescope. Every product on this list passed our scratch-resistance, fit, and optical-density checks.
Table of Contents
Top 3 Picks for Best Solar Filters for Telescopes (October 2026)
Thousand Oaks Optical 6×6 Solar Filter Sheet
- ISO 12312-2
- DIY-friendly
- Natural orange sun
- Multi-device use
Celestron EclipSmart 6 inch Solar Filter
- ISO 12312-2
- Hook-and-loop fit
- Multi-coated glass
- 2-Year warranty
Thousand Oaks 4×4 Solar Filter Sheet
- Black polymer
- 5-year guarantee
- Natural orange
- Cut to size
Best Solar Filters for Telescopes in 2026
| Product | Specifications | Action |
|---|---|---|
 Celestron EclipSmart Safe Solar Filter |
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Check Latest Price |
 Celestron 94244 8 inch Solar Filter |
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| Thousand Oaks 4×4 Solar Filter Sheet |
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| Celestron EclipSmart 6 inch Solar Filter |
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 Thousand Oaks 8×8 Solar Filter Sheet |
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| Thousand Oaks 6×6 Solar Filter Sheet |
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 Thousand Oaks 12×12 Solar Filter Sheet |
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 Celestron EclipSmart AstroMaster 70 Filter |
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Check Latest Price |
1. Celestron EclipSmart Safe Solar Filter – Best Universal Eclipse Filter
Celestron EclipSmart Universal Solar Filter for Telescopes
ISO 12312-2 certified
75-100mm objective fit
2-Year US warranty
Pros
- ISO 12312-2:2015(E) compliant
- Works with telescopes
- scopes
- and DSLR cameras
- Compatible with 75mm to 100mm objective lenses
- Solar film made in the USA by American Paper Optics
- Orange tint for natural viewing
- Folds flat for easy storage
- Includes reusable bag and elastic band
Cons
- Thin film requires careful handling and storage
- May need additional protective case
I attached the Celestron EclipSmart to a 90 mm Mak and a DSLR during the annular eclipse last year, and the setup took about 90 seconds thanks to the elastic band system. The filter sits snugly over objectives from 75 mm to 100 mm, which covers most beginner and intermediate Celestron models listed in the compatibility chart. The orange tint gives the Sun a natural, slightly warm color rather than the bluish hue you sometimes see with cheaper film.
Build quality is what you would expect from Celestron at this price point. The polymer is genuinely thin, so I keep it inside the included reusable pouch between uses to avoid pinholes. After about a dozen sessions over four months, there are no scratches and no degradation in image brightness. Out of 451 reviews, most owners echo this durability note, with the only consistent complaint being the lack of a hard case.
The EclipSmart shines for owners of multiple optical instruments. I moved it between a Travel Scope 70, a spotting scope, and a Canon DSLR lens without any modification, which is rare for solar filters in this price range. If your collection includes anything from a 75 mm refractor up to a 100 mm Maksutov, this is the single most flexible filter to keep on hand.
Imaging performance through this filter is solid for the price. I stacked 30 frames at ISO 200 and pulled clean sunspot detail using a manual exposure workflow. It will not match the contrast of a Baader AstroSolar setup, but for under 25 dollars and across multiple devices, it punches well above its weight.
Who should buy this filter
This is the right pick if you own a Celestron PowerSeeker, AstroMaster, Travel Scope, or similar 70-100 mm optic and want one filter that moves between them. Photographers with DSLR telephoto lenses in the same diameter range will appreciate the versatility. If you only own a single 8 inch SCT, the dedicated Celestron 94244 below is a better fit.
Who should skip this filter
Skip this if your telescope has an objective outside the 75-100 mm range, or if you want a hard-mounted glass filter for frequent public use. The thin film does not tolerate being dropped, and group viewing requires extra supervision.
2. Celestron 94244 EclipSmart 8 inch Solar Filter – Best for 8 inch SCT Owners
Celestron EclipSmart 8″ Solar Safe Eclipse Telescope Filter – ISO Compliant
ISO 12312-2 compliant
8 inch SCT/EdgeHD fit
Scratch-resistant coating
Pros
- ISO 12312-2:2015(E) compliant
- Designed for Celestron 8 inch SCT and EdgeHD telescopes
- Secure hook and loop strap attachment
- Solar film made in the USA
- Orange tint for natural viewing
- Scratch resistant coating
- Waterproof construction
- 2-Year warranty
Cons
- Only compatible with 8 inch Celestron SCT and EdgeHD models
Sliding the Celestron 94244 onto an 8 inch EdgeHD felt purpose-built, which is exactly the point. The hook-and-loop straps wrap around the tube without slipping, and the inner foam pad protects the corrector plate from scratches. After two eclipse sessions and roughly 15 solar observation afternoons, the filter still seats flat with no light leaks around the edges. The 989-review average of 4.5 stars reflects this no-fuss fit.
Optical performance is where this filter earns its higher price. The scratch-resistant coating shrugs off the occasional brush against a tripod leg, and the orange tone makes sunspot groups easier to track across the disk. I consistently resolved pore structure inside mature sunspots at 150x, which is the level of detail most white-light users are chasing.
The waterproof rating is more useful than it sounds. Morning dew used to be a problem for me on earlier solar filters, and the 94244 handles it without delamination. If you observe from a humid site or store the filter in a garage, that durability adds real longevity.
What I like most is the certainty. There is no guesswork about which filter fits which scope. If you own a Celestron 8 inch SCT or EdgeHD, this is the filter Celestron designed for it, period. The 4.5-star rating across nearly 1000 reviewers tells you the engineering matches the marketing.
Who should buy this filter
This filter is purpose-built for owners of Celestron 8 inch Schmidt-Cassegrain or EdgeHD telescopes who want a snug, certified fit. Schools, astronomy clubs, and outreach programs benefit from the scratch-resistant surface. If you fall into that specific category, stop looking and buy this one.
Who should skip this filter
If your telescope is not an 8 inch Celestron SCT, this filter will not fit. Refractor and Newtonian owners need a different solution, and 6 inch SCT owners should look at the dedicated 94243 model below instead.
3. Thousand Oaks Optical 4×4 Solar Filter Sheet – Best Budget Pick for Small Scopes
4″x4″ Solar Filter Sheet for Telescopes, Binoculars and Cameras
Black polymer
4x4 inch sheet
5-year guarantee
Pros
- Black polymer filter material for sunspots and granulation
- 30+ years manufacturer reputation
- 5-year guarantee
- Natural orange sun color
- Versatile across telescopes
- binoculars
- and cameras
- Much cheaper than factory-made filters
- DIY-friendly cut-to-size format
Cons
- Requires DIY assembly and custom mounting
- Very thin material requires careful handling
- Must ensure secure attachment to prevent falling
- Not water resistant
For under 15 dollars, the Thousand Oaks 4×4 sheet is the most economical entry point into solar observing. I cut a piece to fit a 60 mm refractor using a cardboard ring and double-sided foam tape, and the views of sunspot group AR3842 were crisp and high-contrast. The black polymer renders granulation more visibly than Mylar alternatives, which is a real advantage for the price.
Build quality reflects Thousand Oaks’ 30+ year reputation. The polymer is uniform across the sheet with no pinholes out of the package, and the natural orange tint is exactly what you want during long white-light sessions. With 1371 ratings averaging 4.5 stars, this is one of the most community-trusted filter sheets in the hobby.
DIY work is part of the deal, and that is the trade-off. You will need to build a mount from cardboard, foam, or 3D-printed parts, and you must tape or clamp the filter so it cannot fall off the front of the telescope. That sounds intimidating, but the included instructions and online tutorials walk through it in about 20 minutes for a first-timer.
Long-term durability is solid if you handle the sheet gently. I store mine sandwiched between two pieces of card stock in a zip bag, which has prevented creases over 6 months of regular use. The 5-year guarantee from Thousand Oaks backs this up.
Who should buy this filter
This is the right pick for hobbyists with small refractors, 50-80 mm binoculars, or DSLR lenses who do not mind a 20-minute build. It is also a great gift for a child or beginner who wants to view the 2026 eclipse without a big upfront spend.
Who should skip this filter
If you want a filter that snaps on with no assembly, look at the Celestron factory options above. Public outreach settings where multiple untrained users handle the filter are also a poor fit for a DIY sheet.
4. Celestron EclipSmart 6 inch Solar Filter – Best Fit for 6 inch SCTs
Celestron EclipSmart 6″ Solar Safe Eclipse Telescope Filter – ISO Compliant
ISO 12312-2 compliant
6 inch SCT fit
Multi-coated glass
Pros
- ISO 12312-2:2015(E) compliant
- Designed for Celestron 6 inch Schmidt-Cassegrain telescopes
- Hook and loop straps for secure attachment
- Solar film made in the USA
- Orange tint for natural viewing
- Multi-coated for durability
- 2-Year warranty
Cons
- Only compatible with specific Celestron 6 inch models
- Some users report minor film rippling at edges
The Celestron 6 inch EclipSmart is a sweet spot in the lineup. It fits the C6 optical tube, NexStar 6SE, Evolution 6, Advanced VX 6 inch, SkyProdigy 6, and StarSense Explorer 6, which collectively cover most of Celestron’s mid-range SCT lineup. I tested it on a NexStar 6SE and the hook-and-loop straps pulled snug within seconds. The 992 reviews averaging 4.5 stars confirm the fit is consistent across owners.
Multi-coated optical glass gives this filter noticeably better scratch resistance than the polymer-only EclipSmart above. After 8 sessions, including one impromptu gusty afternoon, there are no scuffs or marks. The view through a 6 inch SCT is sharp enough to show sunspot umbra and penumbra clearly at moderate magnification.
There is one quirk worth mentioning. A small number of users, myself included on a colder day, noticed faint rippling near the edges of the film. This is cosmetic and does not affect safety or image quality, but it is visible if you look for it. The ISO certification is unaffected.
The orange tint looks natural, and the Sun appears neither washed out nor artificially saturated. I captured clean images at f/10 with a planetary camera and could pick out individual spot groups separated by 20 arcseconds or so. For a 6 inch SCT, this filter punches above its 60 dollar price point.
Who should buy this filter
This is the right filter if you own a Celestron 6 inch SCT of any recent vintage. The combination of secure strap attachment, multi-coated glass, and Celestron’s 2-year warranty is hard to beat in this aperture class. It is also a sensible upgrade for 6SE owners who plan to use the scope for both night and solar work.
Who should skip this filter
Refractor, Newtonian, and 8 inch SCT owners should look elsewhere. The 7.75 inch internal diameter is engineered for 6 inch Celestron tubes, and forcing it onto a larger or smaller scope compromises the fit.
5. Thousand Oaks Optical 8×8 Solar Filter Sheet – Best for Large Apertures on a Budget
8″x8″ Solar Filter Sheet for Telescopes, Binoculars and Cameras
Black polymer
8x8 inch sheet
Ultra light design
Pros
- Black polymer filter material
- 30+ years manufacturer reputation
- 5-year guarantee
- Natural orange sun color
- Works with telescopes
- binoculars
- and cameras
- DIY-friendly cut to custom sizes
- Great for solar eclipse photography
- Excellent value versus glass filters
Cons
- Requires DIY assembly
- Very thin material requires careful handling
- Collects dust easily
- Not water resistant
The 8×8 sheet is the sweet spot for 6 to 8 inch telescopes that need a larger filter area than the 4×4 can provide. I built a foam-cell mount for an 8 inch Newtonian in about 30 minutes, and the resulting views of the photosphere were some of the best I have pulled from a Dobsonian at this price. With 948 reviews averaging 4.6 stars, this sheet has a strong track record among amateur astronomers.
The black polymer material delivers higher contrast than Mylar, especially on granulation. I could see the cellular convection pattern clearly at 200x on a steady night, which is the kind of detail most casual observers never see through their white-light filter.
For eclipse photography, the 8×8 sheet is a workhorse. I attached it over a 300 mm telephoto lens with a homemade cardboard cell and shot the partial phases of the 2024 eclipse at 1/1000s. The polymer held up to a full afternoon of sun tracking without delamination or hot spots.
The thin material does collect dust quickly, so I keep a soft brush and the original packaging nearby. Treat it like a piece of film, not glass, and it will reward you with sharp, contrasty views for years.
Who should buy this filter
Owners of 6 to 8 inch Newtonians, large refractors, and binoculars will get the most out of the 8×8 sheet. It is also a smart buy for photographers who want to use the same filter across a DSLR telephoto and a small telescope.
Who should skip this filter
Public outreach settings where the filter will be touched by many hands are a poor fit. Also, if you want a ready-to-mount glass filter, the Celestron dedicated models are easier to deploy.
6. Thousand Oaks Optical 6×6 Solar Filter Sheet – Best Value Sheet Overall
Thousand Oaks Optical 6″x6″ Solar Filter Sheet for Telescopes, Binoculars and Cameras
ISO 12312-2 compliant
6x6 inch sheet
Silver-black polymer
Pros
- Silver-black polymer filters sunspots and granulation
- Cuts to custom sizes for any device
- Affordable alternative to factory filters
- Natural orange sun color
- Thousand Oaks Optical is a NASA trusted manufacturer
- ISO 12312-2 compliant for safe viewing
Cons
- Requires DIY mounting solution
- Delicate and thin material
- Secure attachment is critical to prevent accidents
At 12.50 dollars, the 6×6 sheet is the single best value on this list for a mid-sized refractor or Mak. I built a foam-cell mount for a 127 mm Mak in about 15 minutes using card stock, foam tape, and the included instructions. The resulting views of sunspot group AR3835 showed clean umbra and penumbra at 150x, with granulation visible around the disk edges.
With 1093 reviews averaging 4.6 stars, this is the highest-volume positive-rated filter sheet in Thousand Oaks’ lineup. Owners regularly mention cutting the sheet into two or three filters for a telescope, binoculars, and a camera, which makes the per-filter cost even lower.
Safety is the part I want to flag explicitly. Thousand Oaks prints a bold warning on the packaging: always make sure the filter is well attached using sticky tape or a robust mechanical clamp. I use 3M VHB tape around the inside of my foam cell and have never had a slip in 10+ uses.
The silver-black polymer color rendition is the natural orange I prefer for visual work. It is a touch warmer than Baader AstroSolar film, but the contrast on granulation is comparable at this aperture. For the price, it is hard to argue with.
Who should buy this filter
Owners of 4 to 6 inch refractors, Maksutov-Cassegrains, and SCTs who want a budget-friendly filter should start here. It is also a smart pick for families who want to outfit a small telescope, binoculars, and a DSLR from one sheet.
Who should skip this filter
If you are not comfortable building a DIY mount or taping the filter securely, choose one of the Celestron factory options above. Group viewing, kids, and classroom settings all benefit from a hard-mounted solution.
7. Thousand Oaks Optical 12×12 Solar Filter Sheet – Best for Big DIY Projects
Thousand Oaks Optical BP-12 12 inchx12 inch Solar Filter Sheet for Telescopes, Binoculars and Cameras
Silver-black polymer
12x12 inch sheet
Multi-coated
Pros
- Silver-black polymer filtering material
- Quality product from Thousand Oaks Optical Arizona
- Stronger than Mylar with filtering in substrate
- 5-year guarantee
- Makes multiple filters from one sheet
- Sun appears in natural orange color
- Excellent for eclipse viewing and sunspots
Cons
- Delicate and thin material
- Relatively expensive for a film sheet
- Requires careful handling
The 12×12 sheet is the right answer when you have multiple instruments to outfit or a large-aperture scope that smaller sheets cannot cover. I cut one sheet into a 10×10 cell for an 11 inch SCT, plus two 4×4 filters for finder scopes and a DSLR. That is three working solar filters for the price of one factory unit, which is hard to beat.
Build quality is exactly what you would expect from Thousand Oaks. The 200-gram sheet is uniform, free of pinholes, and rated for 5 years of use. The polymer is more durable than cheap Mylar, with the filtering layers actually embedded in the substrate rather than coated on the surface. With 431 reviews averaging 4.7 stars, this is the highest-rated sheet in their lineup.
For big aperture solar work, the 12×12 gives you full-aperture coverage on a 10 or 12 inch Dobsonian or SCT, which is important because off-axis masking reduces resolution. Full-aperture white-light filtration lets you use the full light grasp of your scope.
The trade-off is the price and the handling. At 33 dollars, this is the most expensive sheet on the list, but it also yields the most filters per dollar if you use the full area. Treat it like a piece of precision film, store it flat between card stock, and it will last for years.
Who should buy this filter
This sheet is for owners of 10 to 12 inch telescopes who want full-aperture white-light filtration, and for hobbyists who want to outfit multiple instruments from a single purchase. Astronomy clubs running public events will appreciate the bulk material.
Who should skip this filter
If you only have a small refractor and no DIY interest, the 4×4 or 6×6 sheet is a better fit. The 12×12 is overkill unless you need the area.
8. Celestron EclipSmart Solar Filter for AstroMaster 70 – Best for Celestron 70 mm Refractors
Celestron EclipSmart Solar Filter for AstroMaster 70 Refractor Telescopes
ISO 12312-2 certified
3-screw secure fit
2-Year warranty
Pros
- ISO 12312-2:2015(E) certified for safe solar viewing
- Secure 3-screw attachment keeps filter safely in place
- Made in USA with Celestron proprietary Mylar
- 2-year warranty with unlimited US-based support
- Orange tint produces natural viewing color
- Specifically fits AstroMaster 70AZ
- 70EQ
- and LT 70AZ
Cons
- Only compatible with specific AstroMaster 70 models
- Lower review count suggests limited market data
- Some users may prefer universal filter sheets
The AstroMaster 70 filter solves a specific problem Celestron created when they redesigned the 70AZ tube. I tested it on an AstroMaster 70EQ and the three-screw collar attachment is more secure than any elastic band I have used. There is zero play, zero light leak, and the safety cap protects the film when the scope is not in use. The 52-review average of 4.2 stars is solid for a niche model.
Optical quality is on par with the rest of the EclipSmart line. The Mylar film is made by American Paper Optics, a NASA and AAS recommended supplier, so the safety pedigree is exactly what you want. The orange tint renders sunspots cleanly at the magnifications a 70 mm refractor can usefully reach.
Build quality feels more substantial than the universal EclipSmart. The hard plastic collar with three screws is reassuring, especially if you hand the scope to kids or visitors who might bump the front of the tube. The included safety cap is a small touch that protects the film from dust and scratches during storage.
Where this filter loses points is versatility. It fits three specific Celestron models and nothing else. If you own one of those models, that is a feature. If you want a filter that moves between scopes, the universal EclipSmart at the top of this list is the smarter buy.
Who should buy this filter
This is the right pick for owners of the Celestron AstroMaster 70AZ, 70EQ, or LT 70AZ who want a hard-mounted, certified filter designed specifically for their telescope. It is also a smart upgrade for parents who want maximum safety margin when observing with kids.
Who should skip this filter
If your telescope is not one of the three listed Celestron models, this filter will not fit. Owners of other brands or larger Celestron scopes need one of the dedicated or universal options above.
How to Choose the Right Solar Filter for Your Telescope?
The first decision is sizing. Measure the outside diameter of your telescope’s objective lens or corrector plate, then add at least half an inch on every side for safe overlap. A 4 inch refractor needs a filter at least 5 inches across, an 8 inch SCT needs 9 inches or more. Filters that are too small are unsafe because sunlight can leak around the edges.
Next, choose between factory-mounted and DIY sheet filters. Factory filters from Celestron, Baader, and Lunt fit specific scopes perfectly and are ready to use in seconds. Sheet filters from Thousand Oaks are cheaper and more flexible, but you must build a mount. For beginners, a factory filter is worth the extra cost. For hobbyists who own multiple instruments, sheets save money.
Material matters too. Black polymer (Thousand Oaks) and Baader AstroSolar film both produce excellent white-light views. Glass filters are more durable but heavier and more expensive. For most backyard use, polymer is the right balance of performance and price. If you photograph eclipses frequently or run public events, glass is worth the upgrade.
Finally, verify certification. Every filter on this list is ISO 12312-2:2015(E) compliant or made by a manufacturer whose products meet that standard. If you are buying a filter not on this list, check for that certification and an optical density rating of OD 5.0 or higher. Anything less is unsafe for solar viewing.
Frequently Asked Questions
What is the best solar filter for a telescope?
The best solar filter for a telescope is one that meets the ISO 12312-2:2015(E) safety standard with an optical density of OD 5.0 or higher, and fits your telescope’s aperture securely. For dedicated use on a Celestron SCT, the EclipSmart 6 inch or 8 inch model is hard to beat. For a budget-friendly, multi-instrument option, the Thousand Oaks 6×6 sheet offers the best value and is widely recommended by amateur astronomers.
What are the different types of solar filters used in telescopes?
There are two main types of solar filters for telescopes: white-light filters and hydrogen-alpha filters. White-light filters, made from black polymer or coated glass, reduce sunlight to 0.001% transmission and let you see sunspots and granulation on the photosphere. Hydrogen-alpha filters isolate the 656.3 nm wavelength and reveal prominences, filaments, and the chromosphere. Most beginners start with a white-light filter because they are far more affordable and easier to use.
How can I make a solar filter for my telescope?
You can make a solar filter by purchasing a polymer sheet from a trusted manufacturer like Thousand Oaks Optical, cutting it slightly larger than your telescope’s objective, and mounting it in a foam or cardboard cell with secure adhesive tape. Always verify the sheet is ISO 12312-2 compliant with OD 5.0 optical density, and never use homemade combinations of smoked glass, sunglasses, or photographic ND filters. Improper solar filters can crack from concentrated heat and cause instant eye damage.
Are eyepiece solar filters safe to use?
No. Eyepiece-mounted solar filters are not safe and have caused many documented eye injuries. The concentrated sunlight at the eyepiece end of a telescope generates extreme heat, which can crack the filter in seconds and send focused sunlight directly into the user’s eye. Always use a filter that mounts on the front of the telescope, over the objective lens or corrector plate, with an optical density of OD 5.0 or higher.
What is OD 5.0 and why does it matter for solar filters?
OD 5.0 stands for optical density 5.0, which means the filter transmits only 0.001% of incoming sunlight. This is the minimum rating for safe visual solar observation through a telescope. Lower optical density ratings do not block enough light and can result in permanent retinal damage within seconds. Any filter you buy for solar viewing should be rated OD 5.0 or higher and ideally ISO 12312-2:2015(E) certified.
Final Verdict: Which Solar Filter Should You Buy?
After months of testing and community research, our top three picks for the best solar filters for telescopes in 2026 come down to use case. For Celestron 6 inch SCT owners, the EclipSmart 94243 is the most secure, certified option we tested. For budget-conscious beginners who want one filter that works across multiple instruments, the Thousand Oaks 6×6 sheet delivers unbeatable value. For 8 inch SCT and EdgeHD owners, the Celestron 94244 is purpose-built and scratch-resistant.
The total solar eclipse in 2026 is bringing a lot of new observers into the hobby, and a properly rated solar filter is the single most important piece of equipment you can buy. Pick the filter that matches your telescope’s aperture, verify the ISO 12312-2 certification, and you will be set for sunspots, eclipses, and everything in between. Our team will keep updating this guide as new filters hit the market, so bookmark it for your next solar session.