If you are a Canon user and using one of the Apple devices, make sure you check out the CanonSGLens app on iTunes (link). Some useful tools and references includ DOF calculator, MTBF charts and lens specs.
Description from the App Store
CanonSGLens is a free Canon Singapore App that features detailed lens specifications of all Canon EF and EF-S lenses sold in Singapore. The application also contains a unique interactive simulator that allows you to compare the field of view of two camera-lens combinations whereby the cameras and lenses can be any Canon EOS digital SLR and lens.
- Detailed lens specifications of all Canon EF and EF-S lenses sold in Singapore.
- Compare lens specifications side by side, with differences indicated.
- Compare high resolution MTF charts.
- Compare high resolution lens construction diagrams.
- Field of View simulator featuring multiple photos taken of the same scene in Singapore using different camera-lens combinations.
- Depth of Field simulator.
- Depth of Field calculator.
- In-depth topic with interactive simulators explaining how aperture and shutterspeed affect exposure, depth of field, and motion blur in the various exposure modes.
- Highly visual interactive simulators
- Bookmark your favourite pages
- Add your own notes to any page
- Content optimized for both portrait and landscape orientations
- No Internet connection required
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