FocusTester

It is an application to support the focus on the astrophotography.

You can check the focus of up to around at a time from the center of the photo.
keenai (formerly eyefi) terminal from a digital single-lens camera by using the like (smartphone, tablet, etc.) have been designed on the assumption that transfers astrophotography to.

The focus confirmation of using a live view of the camera can not see the center portion and the peripheral portion of the photo at the same time.
This app allows you to check the focus state of up to around from the center of the photograph in the average image and a graph.

function
· JPEG only correspond.
- is divided into 40 about the area in the radial direction and the circumferential direction of concentric circles and analysis.
- averages the star image of each of the regions, create an image, such as a spot diagram.
- the variation of the light from the center of the averaged star image and the calculated graph.
Graph creates two of the radial and concentric direction from the center of the photo.

operation
- Try to take celestial photo (JPEG) to save the terminal.
Open filer astronomical photos of the trial taking from (file manager) in FocusTester
  Or, send to FocusTester shared.
• When the screen by tapping the left and right of you open another file in the same directory.
- in the same directory when you save a new file will open automatically.
• If the app was launched from the launcher, you can try the execution of the analysis in the demo image.


View of the screen

If the screen is horizontal,
Star image on the left side of the screen, to display the graph to the right
Star image is the distance from the center the center image in the upper left, laterally
In the longitudinal direction in the direction from the center you have side-by-side image.
Direction from the center is 45 degrees at a time counter-clockwise, starting from the right direction.

The depicted figures in star image,
Variation from the center of the RGB to the left
The number of composite of star image below.

Distance above the graph from the center on the horizontal axis, the variation in the vertical axis,
Below is a variation direction, the vertical axis from the center to the horizontal axis.

Unit of each numerical value if the resolution of the focal plane in Exif,
You are viewing metric.
If it does not are in pixels.

You are viewing the Exif read to the right edge of the screen.
The camera body from the top, lens, is shooting settings.
From the F value during shooting set for the reference under the
You are viewing the size of the calculated Airy disk.


You me an example of using the web site.
https://sites.google.com/view/focustester/%E5%AE%9F%E7%94%A8%E4%BE%8B


Caution
• In order to perform image processing at high speed, and then use a large amount of RAM (heap).
  In the case of 20 million pixels in a rough estimate, you need 160MB of about RAM (heap).
  For this reason, by the terminal may app force closes due to the occurrence of the Out Of Memory.
  Because even if there is a vacancy in the RAM was confirmed at hand of the terminal, such as there is also a terminal that is rejected from the OS,
  I do not know and do not try to move is if it works.
For noise removal and chromatic aberration detection has with the exception of the star that is a false color.
  Therefore, the number of samples is reduced calculation will collapse in the false color prone situation, such as a large sensor and high-performance lens.

Please
- There is a place still unstable as described above.
  We hope you are able to operate report if it is good.


Permissions
android.permission.READ_EXTERNAL_STORAGE
• Use the file in the external storage in order to search / analysis.
android.permission.WRITE_EXTERNAL_STORAGE
• Use to store the analysis results to the external storage. (In the current version has saved function inactivation)

Otherwise
largeHeap = "true"
And image processing to ensure a large heap because there is a need to perform at a high speed.