You’re about to look at the Sun. On purpose.
Most people never do this.
If you’re here, you’re already curious. That’s enough to get started.
START HERE
Threaded camera filters use thread size (Ømm). Everything else uses outer diameter.
Measure once. Order confidently.
For slip-on filters, the only number that matters is the outer diameter of the front of your equipment.
Threaded camera filters use the thread size (Ømm) instead.
That’s it. No math. No guesswork.
Telescope
The most common setup.
Slip-on filters mount to the front of the tube, not the eyepiece.
If you’ve got a telescope, measuring the outer diameter is all you need.
Shop NowBinoculars
Yes—you can use binoculars.
Slip-on filters are sold in pairs, and the same sizing rule applies.
Measure the outer diameter of each barrel once, and you’re set.
Shop NowCamera lens
There are two options, depending on the filter type.
Threaded filters use the thread size (Ømm).
Slip-on filters use the outer diameter of the front of the lens.
Both are amazing. The method of attachment is just different.
Shop NowGlass or thin-film? It depends how you’ll use it.
Glass filters are durable and stable. They’re built for frequent use, outreach, and gear that gets handled a lot.
Thin-film filters are lightweight and lower cost. They’re easy to travel with and excellent for eclipses and casual observing.
Same safety. Same view. Just different trade-offs.
Standards like ISO 12312-2 apply to solar viewing eyewear for unaided, direct viewing and not to optical solar filters used on telescopes, binoculars, or cameras. We explain this distinction in more detail on our ISO 12312-2 scope page.
What’s worth looking for
- Sunspots and evolving surface detail
- Planetary transits across the solar disk
- Partial, annular, and total eclipses
- Day-to-day solar activity that actually changes
Eclipses are only the beginning.
Ready to choose a filter?
If you’ve got your measurement, you can go straight to the filters.
On the next page, you’ll choose your filter type and size range.
Handcrafted solar filters for real white-light observing.
Made by hand in North Carolina.
Built for people who actually want to see what’s happening up there.