Direct answer: For capturing solar eclipses, choose ISO-compliant solar filters for telescope viewing, paired with neutral-density options for photography when needed. This guide highlights five top filters and sheets that balance safety, image quality, and ease of use for amateur astronomers and photographers. Best bets are Celestron EclipSmart filters for telescope compatibility, and Thousand Oaks Optical sheets for DIY setups. The included buying guide helps compare safety, compatibility, and practical use for each option.
| Product | Best For | Why It Stands Out |
|---|---|---|
| Celestron – EclipSmart Safe Solar Eclipse Telescope Filter (B0CH45ZBKV) | Telescopes and cameras | ISO 12312-2:2015(E) compliant; secure fit; portable |
| Celestron 94243 EclipSmart Solar Eclipse Filter | 6” SCT telescopes | Secure fit; ISO compliant; reliable for snug attachment |
| Celestron 94244 EclipSmart Solar Eclipse Filter | 8” SCT/EdgeHD telescopes | ISO compliant; robust fit with secure straps |
| Thousand Oaks Optical 6″x6″ Solar Filter Sheet | DIY solar viewing/photography | Flexible sizing; durable polymer; affordable |
| Thousand Oaks Optical 8″x8″ Solar Filter Sheet | DIY setups for larger scopes | Strong, long-lasting; five-year guarantee |
Celestron EclipSmart Safe Solar Eclipse Filter
This ISO 12312-2:2015(E) compliant solar filter is designed for direct sun viewing and solar photography with a telescope, spotting scope, or DSLR. It features adjustable side panels for a secure fit to instruments with an exterior diameter of 75mm to 100mm, making it a versatile choice for many setups. The filter folds flat for easy storage in the reusable bag, helpful for field use. Best for hobbyists who need a reliable, all-in-one filter that travels well.
Best for: Amateur astronomers who want a ready-to-use, safe filter that works with multiple optical setups and supports basic eclipse photography. Limitations: Fit depends on having a compatible objective diameter; avoid using with accessories outside the supported range.
Celestron 94243 EclipSmart Solar Eclipse Filter
This filter is ISO 12312-2 compliant and designed for Celestron 6” Schmidt-Cassegrain telescopes. It uses a solar-safe film and includes two hook-and-loop straps to ensure a secure fit at the objective. It is a solid choice for observers who own or plan to use a 6″ SCT and want a true solar viewer with a reliable attachment method. Best for: Users with a 6″ SCT seeking a snug, ISO-compliant protective layer. Caution: Ensure the mount is clean and dry before installation to prevent slippage.
Celestron 94244 EclipSmart Solar Eclipse Filter
Designed for 8” Schmidt-Cassegrain and EdgeHD telescopes, this ISO-compliant filter uses a secure fit with straps to hold the filter in place. It suits observers upgrading to larger apertures or those who want a consistent solar viewing and imaging experience with bigger optics. Best for: Users with 8” SCT or EdgeHD systems who need dependable ISO-compliant protection. Limitation: Larger filters can be bulkier for field transport.
Thousand Oaks Optical 8″x8″ Solar Filter Sheet
Black polymer solar filter sheets are common for visual sunspot and granulation viewing through telescopes, binoculars, or cameras. These sheets from Thousand Oaks Optical offer a DIY approach with a five-year guarantee, letting users cut to fit their specific equipment. Best for: DIY enthusiasts who want a cost-effective, long-lasting solar filter option. Caution: This is a sheet filter, not a ready-made system; ensure proper handling and securing method to avoid gaps or misalignment.
Thousand Oaks Optical 4″x4″ Solar Filter Sheet
Another DIY option from Thousand Oaks Optical, this 4″x4″ sheet provides a compact, affordable way to tailor filters for small telescopes or accessories. Best for: Small-aperture instruments or experimenting with custom filter sizes. Limitation: Requires careful fabrication to ensure a tight, uniform fit and to maintain ISO safety.
K&F CONCEPT 62mm ND100000 Solar Eclipse Filter
This ND100000 neutral-density filter is designed for photography, offering a very dark layer to capture solar eclipses with proper exposure. It uses a high-quality AGC optical glass and an aluminum frame with multiple coatings to minimize ghosting and reflections. Best for: Photographers seeking long-exposure control and natural color during eclipse photography. Caution: It is not a solar safety filter for direct sun viewing—do not use for eye protection. Use only with appropriate solar-viewing filters when viewing with your optics.
Buying Guide: Key Solar Eclipse Filter Considerations
What should you check before buying?
- Safety standard: For direct sun viewing, prioritize ISO 12312-2 compliance and dedicated solar filters rather than generic ND filters.
- Compatibility: Confirm telescope diameter or mount type and whether the filter uses hooks, loops, or adjustable panels for a secure fit.
- Intended use: Distinguish between viewing-only filters and photography filters. Photography kits may require ND or neutral-density modes for exposure control.
- Material and durability: Look for certified solar film or robust polymer sheets; ensure the filter can endure field use without warping or misalignment.
- DIY vs. ready-made: DIY sheets offer customization and cost savings but need careful handling to maintain safe, uniform coverage.
- Storage and portability: Reusable bags, cases, and fold-flat designs improve field readiness.
FAQ for Solar Eclipse Filter Buyers
- Q: Can I use an ND filter alone to view the Sun safely? A: No. ND filters are not designed for direct solar viewing and do not meet safety standards for eye protection. Use ISO-compliant solar filters for viewing and safe photography with proper setup.
- Q: Are all EclipSmart filters ISO compliant? A: Yes, the EclipSmart line includes ISO 12312-2:2015(E) compliant filters designed for direct sun viewing with support for telescopes and cameras.
- Q: Can I use filter sheets for any telescope size? A: Filter sheets can be cut to fit certain dimensions, but ensure the final fit is secure and does not cause light leaks or accidental exposure.
- Q: Which product is best for a beginner with a small telescope? A: The Celestron EclipSmart options with adjustable fits are ideal for beginners due to their simple attachment and official safety standard compliance.
- Q: Do DIY solar filter sheets come with a warranty? A: Thousand Oaks Optical sheets typically include a multi-year or five-year guarantee depending on the product; check the seller details for specifics.
- Q: Can I photograph the Sun with the filtered telescope? A: Yes, but ensure you use a solar-safe filter for viewing and use appropriate photography filters and exposure settings to avoid sensor damage.