Neutral density filter

ND1000000 filter — 20 stops

Convert any shutter speed for a 20-stop neutral density filter.

20
Stops of light reduction
6.0
Optical density (ND x.x)
9.537e-05%
Light transmitted
×1,048,576
Exposure time multiplier

ND1000000 exposure conversion#

Meter without the filter, then multiply the shutter time by 1,048,576.

Without filterWith ND1000000
1/4000 s262.1 s
1/2000 s524.3 s
1/1000 s1048.6 s
1/500 s2097.2 s
1/250 s1.2 h
1/125 s2.3 h
1/60 s4.9 h
1/30 s9.7 h
1/15 s19.4 h
1/8 s36.4 h
1/4 s72.8 h
0.5 s145.6 h
1 s291.3 h
2 s582.5 h

ND calculator & countdown timer#

Shutter speed with filter—
Light reduction—

What a ND1000000 filter is for#

ND1000000 (also sold as ND 6.0 or “20-stop”) is typically used for: Solar photography (only with certified solar filters!) and extreme long exposures.

For video: in bright sun at f/2.8 and ISO 100 you need about 6.4 stops of ND to shoot at 1/50 s (the 180° shutter rule at 25 fps). This filter alone is enough.

Tips: compose and focus before attaching dark filters, cover the viewfinder eyepiece on DSLRs to stop light leaks, and expect a colour cast with strong NDs — shoot RAW and set white balance afterwards.

Other ND strengths#

Frequently asked questions#

How many stops is a ND1000000?

20 stops — it passes 1/1,048,576 of the light (density 6.0).

What shutter speed with a ND1000000 filter?

Multiply your unfiltered shutter speed by 1,048,576. For example 1/125 s becomes 8388.6 s.

Last updated October 03, 2026 · How we calculate · Sources