# Camera / Viewport behavior

**URL:** https://discourse.vtk.org/t/camera-viewport-behavior/8531
**Category:** Support
**Created:** [May 19, 2022, 6:25pm UTC](https://discourse.vtk.org/t/camera-viewport-behavior/8531 "2022-05-19T18:25:47Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![Olivier](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/o/d2c977/32.png) [@Olivier](https://discourse.vtk.org/u/Olivier)
#### Post date: [May 19, 2022, 6:25pm UTC](https://discourse.vtk.org/t/camera-viewport-behavior/8531/1 "2022-05-19T18:25:47Z")

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Hi friends,

When displaying a 2D scene with ParallelProjectionOn(), the following behavior occurs :

- When the WIDTH of the viewport is changed, the scene scale is not changed, objects stay at their current “visual size”, only the camera focal point is kept in the middle of the viewport.

- When the HEIGHT of the viewport is changed, the “visual size” of the objects is changed.

Question : how can I keep object “visual size” the same while changing viewport HEIGHT ?

**Original Size**

 ![original](https://discourse.vtk.org/uploads/default/original/2X/4/4a20d332b99014982cc9c524e2d48ac977c34aa9.jpeg)

**Width increase =\> objects keep their visual size**

 ![original + W](https://discourse.vtk.org/uploads/default/original/2X/e/eb6fff1bc20471f16ef071700f7a74ea8dfcd588.jpeg)

**Height increase =\> objects appear larger, and are actually cut**

 ![original + H](https://discourse.vtk.org/uploads/default/original/2X/0/0a5afdaa3c38aa2bd128876bded06644105a9491.jpeg)