For
some time I have looked for a software for my phone that would enable
checking the depth of field (DoF) for given exposure parameters.
Unfortunately, I havent found anything working, so I decided to write
it myself.
The program is designed for Symbian phones with Series 60 v.3 user
interface ("S60 3rd edition", i.e. for all Nokia N and E models, some other phones, too).
It will run on S60 5th edition (touch screen) devices, but if the phone does not have keyboard (arrows) you'll not be able to resize the plot.
It will not run on legacy devices, i.e. those based on Symbian v7.x or below.
It displays the DoF plot in three forms:
- DoF as a function of distance
- DoF as a function of aperture
- "Intuitial" DoF as a function of distance
On the plot, the hyperfocal distance
or aperture (i.e. the aperture at which the DoF reaches infinity) is
marked with a dashed line and currently set distance or aperture with a
red line. Of course, the program also shows the numerical
information:
- hyperfocal distance
- DoF for currently set distance
- DoF for the hyperfocal distance
- blur of the background (at infinity)
DoF does not depend on the frame or sensor size.
It does, however, on the
blur circle
(sometimes called circle of confusion). It defines how big
blur can still be regarded as "sharp". Obviously, it depends on
the ratio between the print and the frame sizes. For example, for 10x15
cm print made from 35 mm film (or so called "full frame" DSLR) the blur
circle is typically 0.03 mm. However, if you increase the print size 4
times to 20x30 cm the acceptable blur will become twice smaller, i.e.
0.015 mm. On the other hand, if the print is typical, but the recording
frame is smaller, the blur circle has to be decreased, too. For
example, blur circle for a Canon camera with crop factor of 1.6 is
0.019 mm. In the program I have added 6 common values and assumed
they apply for typical prints (about 10x15 cm):
- Full frame or 35 mm film (blur circle = 0.03 mm)
- Canon 1D (blur circle = 0.023 mm)
- APS-C DSLR, for example Nikon, Pentax or Sony DSLR (crop factor = 1.5, blur circle = 0.02 mm)
- Canon DSLR (crop factor = 1.6, blur circle = 0.019 mm)
- Sigma DSLR (crop factor = 1.7, blur circle = 0.018 mm)
- 4/3s DSLR, for example Olympus E-series (crop factor = 2.0, blur circle = 0.015 mm)
Obviously, the blur circle may be set manually. To do it, select:
Options > Set parameter > Blur circle > Other
The program is available in
English, Polish, Spanish (thanks, Alejandro!), Finnish, Italian
(thanks, Asblut!), Russian (thanks, Nikolai!), German (thanks Rob!) and French (thanks Yannick!).
Perhaps later I will add other languages.
Please, take into account that it is a beta, I don't take any responsability
regarding possible damage etc. On the other hand, it is 100% freeware:
use it, put on your webpages and have fun! So, if you are not scaried
away, you can download it here (click on the file name):
kmk_DoF.sisx (version: 0.15.0, compiled on 24.10.2010)
I prepared also a version with imperial units (feet and inches), but since internally
it uses metric system and because I do not use it personally, it might be less "smooth"
than the main version. If you would like to test it, download it from here (click on the
file name):
kmk_DoF_feet.sisx
How to use it (Note: shortcuts changed at ver. 0.15!):
- Install on the phone (you have to enable installing untrusted programs!*)
- key 1 increases aperture
- key 2 decreases aperture
- key 3 opens a dialog to set aperture manually
- key 4 increases focal length
- key 5 decreases focal length
- key 6 opens a dialog to set focal length manually
- key 7 increases distance
- key 8 decreases distance
- key 9 opens a dialog to set distance manually
- arrow left zooms in X axis
- arrow right zooms out X axis
- arrow down zooms in Y axis
- arrow up zooms out Y axis
- middle button opens a quick access menu
- key * switches between plot modes
- key 0 switches between plot and details modes
- key # enlarges (while pressed) the plot to full screen
*) To enable installing untrusted programs set:
Menu > Tools > App. mananger > Options > Settings > Software installation > All
The program works fine on my N95-1
and I don't expect any problems with other compatible devices, either.
If you have any comments, please send them to
kkord@wp.eu
(mark in the title that it is about "kmk_DoF").
( last modified: 01.02.2009 )