I've got a very simple question here, and it's driving me nuts.
All I want to do is put a very simple logo in a new project (File > New). Thing is, I want the height of my project to be 8 cm (I don't care about the width) so I can bring my logo in there, scale it down to the size of the project and print it so on my sheet of paper, my logo will have a height of 8 cm.
With all those Image > Image Size and Canvas Size (especially the resolution numer wich I don't get), I seem to get stuck. My logo never comes out the size I want it to be. I've read tutorials, read Adobe's Help section, nothing.
I'd set the New File Image Resolution to 300 pixels/inch. This is generally considered to be Hi-Rez. You'll have a canvas height of 945 pixels - (8cm @ 300ppi).
Are you Pasting or File/Place(ing) the image?
Regardless, once the logo is in your PSD file, the layer should be highlighted in the Layers palette - if not, click on the layer.
If you pasted the image, make sure 'Show Transform Controls' is checked.
If you placed the image, the transform controls are ready and waiting.
Surrounding the image is the Bounding Box, eight squares surrounding your image. One on each corner, and one on each of the four sides.
Also, make sure View/Show Extras is enabled.
Press Ctrl + V, or click on the Move Tool from the tool palette.
Hold the Shift button and click on any of the four corners, with the Move Tool, and resize.
You hold the shift button, when resizing, to constrain the proportions of your image as it's resized.
If you can't see the bounding box, try zooming out with the Navigator tab or by pressing Ctrl + - (minus).