Problem Scaling Pictures - lose quality

Hi, I have CS2 photoshop, and I hear it uses vectors now as well, but it doesn't seem to help in making images any clearer, they still blur up when I try to increase their size? I thought it was resolution dependant?

Can someone explain how to enlarge objects or images without losing its quality at ALL? I'm printing a design for a tshirt, so I don't want to have the design losing any quality as the shirt sizes get bigger.

Thanks

I don't believe you will be able to enlarge a picture without losing ANY quality at all.

The image you're using likely isn't in a vector format - so it's going to lose quality when scaled regardless of whether or not Photoshop can work with vector images.

Before you ask, there isn't any real way to convert an image to a vector format automatically - they need to be created as one in the first place.

Most images people see are in a raster format (all if you count that vector images are technically converted before or while being displayed) - the image stored is defined in terms of the colors of each pixel...scale it up, and you're just filling more pixels with the colors already there (the bluriness is do to most programs interpolating colors to make things look smoother)

Vector images are saved basically as a set of mathematical parameters and colors/gradients - combining to form shapes. This ranges from simple lines, to circles, to the almighty bezier (or other variant) curve. Since they're defined this way, the final image can be seen at any resolution while retaining the original level of detail).

As for using vectors in Photoshop - I wouldn't be very helpful, my experience with them is limited to CADD and a minimal use of certain concepts in some programs I've worked on.

The file size for a large photo would enormous if the level of detail was kept. You'd only get a few pics on a camera at most.

Oh and Vectors are very important in Flash.