Welcome to Exposure Assist! This app lets you calculate the camera settings when you are working with long exposure times. Usually in those cases the camera's automatic metering can't be used, since the light intensity that reaches the camera's light meter is below the level it can measure. Calculating these settings manually on site can be tedious, which is why this app was created. The app does not use the phone camera, instead, it's a specialized calculator app for photographers using tripods for long exposure times.The app is designed around the "exposure value" formula and it is able to separately solve each parameter of the exposure triangle: aperture, shutter speed and ISO. If you adjust one of the settings, one or both of the other settings will also have to change if you intend to maintain a similar image brightness. The EV number (exposure value) represents the combination of these settings. The app uses the EV number to "lock" the exposure so that once it's known, you can use the app to calculate different combinations of settings that produce an equivalent exposure (similar brightness).The app allows you also to quickly see the effect of a neutral-density (ND) filter on the exposure time. See the first screenshot for a usage example where the shutter speed has been calculated for a 10-stop ND filter.The second and third screenshots illustrate a case from astrophotography: first the night sky image is captured using some (figurative) settings appropriate for capturing pin-point stars (EV calculation in second screenshot). Then in the third screenshot the app is switched to solve the shutter speed for a foreground exposure that uses a much longer exposure time. Now the two equally bright exposures could be blended in a post-processing software, forming a single high quality image with a noise-free foreground. Similarly, the app can be used to calculate the required settings for a star trail image.The app allows you to calculate the parameters with more precision than cameras do. For each calculated value the app also shows the rounded values that are commonly displayed by the camera. That is, if the value is within the range of commonly supported values.