Why thirdstop
  • Adjusting shutter speed, aperture and ISO can be confusing. Let the Exposure Calculator help you through the process
  • The calculator will help you think through your shot, considering depth of field, compression and quality so you take the right shot by design and not by luck
  • It’s like having a coach on every shoot to help you know your options.
  • Concentrate on composition and the story you're telling with your photo, not on memorizing lists of numbers
  • You purchased a good camera, now put it to work!
Need more info?View Video
How thirdstop works
Select your camera's ISO setting
Push your shutter button halfway to find the camera recommended shutter speed and aperture
Line up the shutter speed and
aperture recommended by the
camera
View all effective shutter speed
and aperture combinations at a
glance
Or
line up the desired shutter speed
and aperture and read what ISO
setting is required
Price $19.95
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