FocusChart helps you deal with the problems of front-focus or back-focus of your dslr camera.
It often happens that when you focus on a subject, it does not appear razor sharp on the photo as it should. Sometimes, the elements in the front are sharper, that is a front focus. Sometimes, elements behind are sharper, that is a back focus.
Using FocusChart, you can take pictures with a precise measure of the focus shift. Then with the autofocus micro adjustment of your camera, you can set it to correct the problem and have razor sharp images (finally).
FocusChart provides you several charts to help you fine tune the autofocus of your camera.
This chart is based on the famous Spyder LENSCAL. It is made of a contrasted target and a ruler to measure the autofocus shift. In order to use it properly, you need to incline your android device to 45° from the horizontal plan. In order to do so, a spirit level is included in the app that shows you when the angle is correct.
To ensure the chart is clearly visible from your camera point of view, you can zoom in/out every element with a pinch-to-zoom gesture.
This chart displays only a ruler. Make the focus on the 0 line and measure the autofocus shift right away. As previously, ensure the angle is 45° from the horizontal. You can stretch the ruler in or out with a pinch-to-zoom gesture.
When double-tapped, the ruler is set to be graduated in centimeter.
Usint the (two) moiré charts available, when the focus is correctly made, the photo will show ... moiré(!). This is also a very accurate way of knowing if the autofocus is perfectly tuned.
To use it, put your android device vertically, the spirit level will help you set the android device to 90°. Take the photo and control it on the rear screen.
Don't hesitate to contact us if you wish to see more different charts in the app.