Exposure Triangle Calculator
Find the shutter time, aperture or ISO that keeps the same exposure after you change one setting, with EV at ISO 100 and the stop shift per setting.
Exposure and Camera Settings
5 tools
Which Exposure and Camera Settings tool do you need?
| Tool | What it answers |
|---|---|
| Exposure Calculator | Exposure value is EV = log2(N² ÷ t), where N is the f-number and t the shutter time (s). |
| Exposure Triangle Calculator | The exposure triangle links aperture, shutter time and ISO: light recorded scales with time × ISO ÷ f-number². |
| ND Filter Calculator | An ND filter cuts light by whole stops, and every stop doubles the shutter time. |
| Reciprocity Calculator | Film loses sensitivity in long exposures, so a metered time over one second must be lengthened. |
| Shutter Speed Calculator | To keep the same exposure, multiply the metered shutter time by (new f-number ÷ old f-number)² and by (old ISO ÷ new ISO). |
All tools
Shutter Speed Calculator
Find the shutter speed that keeps your exposure when you change aperture or ISO. Shows exact seconds, the nearest 1/3-stop setting and the stop change.
Exposure Calculator
Turn an f-number, shutter speed and ISO into an exposure value referenced to ISO 100, with the light level those settings match. f/16 at 1/125 s is EV 15.
Reciprocity Calculator
Corrects metered long exposures for film reciprocity failure using Ilford's Tc = Tm^P formula, with exponents for HP5, FP4, Delta and Kentmere stocks.
ND Filter Calculator
Convert a metered shutter speed into the long exposure you need behind an ND filter, from ND2 to 20 stops, with exposure factor and optical density.