Question: how to make a high quality pdf from photoshop?
Answer: choose File, Save As, and select "Photoshop PDF"
Click "Save"
In the "Save Adobe PDF" dialog, set the "compatibility" to the highest version you can.
In the "General" tab, select "Preserve Photoshop Editing Capabilities"
In the "Compression" tab select "Do Not Downsample" from the options.
Save.