Sight-to-Size app for iPhone and iPad

4.0 ( 3730 ratings )
Photo & Video Education
Developer: Twinscape Software
Current version: 1.0, last update: 1 year ago
First release : 17 May 2011
App size: 140.36 Kb

Sight-to-Size is an app to help when drawing with pen and paper. The app makes it possible to compare a drawing in progress with the subject being drawn so that possible problems with proportions and perspective can be seen. This means that one can spot where a drawing is off and identify those parts that need to be observed more closely.

In the app, this is done by showing the drawing transparently on top of the subject being drawn. This is completely interactive, so the drawing can be zoomed to the same scale as the subject and viewed with different transparency settings.

For example, Sight-to-Size can be used to check the accuracy of a plaster cast drawing. The app is motivated by the Sight-Size method for drawing.


Images can be selected from either the photo library or taken using the built-in camera. After two images are selected the following controls are available:

Slider: Transparency of images.

Tap: Flip transparency.

Lock/Unlock: Locks images so they can be panned and zoomed either independently or locked together.

Image options:
• Mirror view
• Grayscale view
• Animation
• Save to photoroll

Please note: In recent versions of iOS (like iOS8 and iOS 8.1), Sight-to-size can crash when using the camera to import images. After this, the app can enter a state where it freezes on startup. In this case: delete the Sight-to-Size app, restart the iPad/iPhone device, and redownload the app via the App Store. [For instructions how to do this, please see]. If you experience this problem, please avoid using the camera feature in Sight-to-size. For the moment, a workaround is to use the Camera app to take pictures, and only import images via the camera roll.

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