Designed for use on your 70-90mm aperture nighttime optical tube assembly for viewing the sun or solar eclipses, the iOptron 70mm Solar Filter for White-Light Observationfits over the front of the OTA's dew shield and is held in place with three thumbscrews. For longevity and safety the filter is made of an infused polymer material called SolarLite to ensure that it will not develop pinholes or scratches — and since it's rigid, it won't tear or puncture like film filters can. It has an optical density of 5 that transmits just 1/1000th of 1% of the harmful intense light from the sun to make it safe to view.

To ensure the filter will fit your OTA, simply measure the outside diameter of the dew shield — the filter's mounting ring has an inside diameter from 84-106mm so as long as the outside diameter of the dew shield falls in that range, it will fit. Remember to practice safe solar viewing techniques and never look directly at the sun without certified solar viewing glasses and equipment.

Adapt Nighttime Scope for Solar Viewing    Optical Density of 5    70mm Clear Aperture    Fits Most 70-90mm OTAs    84-106mm Inner Diameter    Durable and Reliable SolarLite Polymer

Related Questions and Answers

Q: 1. what is the ND equivalent of this filter?

A: The DayStar Filters 70mm White-Light Universal Lens Solar Filter (Single, 65-89mm OD) is a solar filter and not an ND. So there is no density rating for it.

Q: 2. What size should I get for a Nikon 18-200 lens? The current screw-on filter says 72mm.

A: The 65-80 MM works perfectly on my Nikon with a 72mm lens cap. Since the camera will be pointing UP, it can't just fall off. As to folding the tabs, it doesn't matter which one you start with, just fold down the little tab on the left side first (looking at the word side). The little tab will be at a 45 degree angle, Makes it easier to get the big tab located on the adjacent right side into the notch, then fold the little tab back up to hold the right tab in place.During an eclipse, you want the filter to slip off/on super easy!

Q: 3. Will I need this to take picture of the eclipse with my Sony A99?

A: Absolutely! All cameras risk (will sustain) light sensor damage when imaging the Sun without a proper filter with the exception of the 2 minutes or so of totality of a total eclipse. This only takes place in the ribbon of totality which during the upcoming Aug. 21st event will be only 70 miles or so wide and at very specific times per location.

Q: 4. 70 mm size, would it work on my 2 lenses with filter sizes are 77 and 62 mm or should I also buy the smaller size?

A: For use on a 77 mm filter size , we recommend the DayStar Filters 90mm White-Light Universal Lens Solar Filter (Single, 85-99mm OD) B&H # DAULF90 90mm = 3.54331 inches. 77 mm = 3.0315 70 mm = 2.75591 inches. 62 mm = 2.44094 inches.

Q: 5. What is the difference between this product and a Neutral Density 5.4 Solar Eclipse Filter besides the price?

A: The difference is safety and your vision! The solar filter is ISO 12312-2 Compliant. The neutral density filter is NOT. Read the ISO Warning on the product. ISO 12312-2 Compliant Warning: Viewing the Sun without proper protection can cause permanent eye damage, blindness, and equipment damage. Always use an approved ISO 12312-2 certified solar filter when observing the Sun through optics or cameras. Never use photographic neutral density filters for direct solar viewing, viewing the sun through an optic, or when using cameras with an optical viewfinder. Ensure the solar filter is ISO 12312-2 Compliant. And buy from a reputable source like B&H. Many of the answers to this question are inaccurate and dangerous. I have flagged those answers to B&H so hopefully those answers have already been removed. When you are looking at the sun either directly or through optics, get your answers from experts in the field.

Q: 6. What size should I get for Canon 70-200?

A: If you go to Daystar website or call them on the phone, I think that is where I read that if you have the 77MM pro lens, meaning it is 77MM in diameter then get the 65 - 89 Solar filter. I have the 70-200 F2.8 non IS lens. I did not put it on yet.

Q: 7. Will this fit the ASTROMASTER 70EQ Telescope?

A: Any chance to fit Sky-Watcher 70mmDo u know ?

Q: 8. What size should I get for a lens using a 77mm filter, Canon 100-400?

A: Get the 65-89mm OD (outside diameter). I have a 77mm lens and it fits perfectly.

Q: 9. Are these left over from 2017? That's the date on the product photo.

A: The DayStar Filters 70mm White-Light Universal Lens Solar Filter (Single, 65-89mm OD), that B&H offers are not left overs at all.

Q: 10. I have a 24-120 mm using a 77 mm filter. The lens hood diameter is 110 mm. Should I use the lens hood during the eclipse?

A: It is a matter of opinion but I would recommend using the hood always. Even if the sun is directly in the frame and the hood cannot stop the flares, the hood still provides safety protection in case the camera is dropped. Since the Daystar filter is not large enough for the hood, this screw on ND filter can be used for solar protection instead: https://bhpho.to/2m7h8oX