I scanned some sketches and changes some colours in photoshop,then I saved the image as a psd file on my desktop.The problem now is that I want to use them in inDesign and when I insert them they have huge pixels.In photoshop they were ok and I even changed the 'display performance' to high resolution.What is the problem? (sorry for my english :D)
Are you sure you changed from 'Preview' to 'Overprint Preview' in the View menu? InDesign displays at low resolution preview while you're working, so artwork may appear pixilated.
You can check 'Overprint Preview' on and off at intervals while you're working to see a better representation of what will print, but I wouldn't leave it on all the time - especially if you're working with large files, it will slow the application down.
Another factor might be whether the profile of the document is set to print or web. You can check the image resolution in the Links panel, to see if you have the appropriate Actual & Effective resolution for your output device.
Increasing the dimensions of your image (width and height) may decrease your effective pixels per inch. For instance, if an image is 72ppi at actual size (100%), and you increase the dimensions of that image in InDesign (i.e. ask the same amount of pixels to cover more square inches), or if your device outputs/displays at a higher resolution than 72ppi, your actual ppi may be 72, but your effective ppi would be less than that. There's more information here: http://blog.rockymountaintraining.com/adobe-indesign-why-do-my-images-look-so-bad/