Tilting an image while keeping sizes

Hi G Pires,

As I understand it, you want the length of each side to remain the same, is that correct? Use Edit > Transform > Skew, then hold Shift as you drag the handle on the right center upwards. Look in the options bar at the number and type in 30° for the "Set Vertical Skew" control (far right) before you accept the transformation if it's not exactly what you want.

I added copies of the rectangle above and to the side so you can see at a glance that the length has not changed. My vertical skew is 15°.

~ Jane

Only some transform will not change the shape layer side length. The Rotates and flips. 

The only Transform that can do what you want to do is Transform Distort.  However it will not be automatic or easy to do.  With Distort you can Skew the Square then make the shape narrower to reduce the length of the elongated sides caused by screwing the square.  The problem is there are not length displayed the the shaped sides.  

So you add Chucks Guide a circle shape ovet your shape

Place some guides on the edges then draw a circle at one corner.

Use transform to get your 30 degrees.

Create two new guides to show where the "square crosses the circle.

Use free transform, holding the ctrl/cmd and move the left sidt so that the end point lines up with the guides.

Ctrl/Cmd t for Free Transform on the square. Then hover your mouse on one of the corner handles until it  becomes a curved arrow and it should keep shape as you rotate it.

If there is a problem doing that, place the smaller square on a separate layer and try the rotation there.

Keep the original layered project as a master file, and Export a flat jpeg/png copy or simply flatten the master when done.