Originally Posted by JoyB
What is the method so no pixilation happens when they are enlarged for printing.
That's part of the problem, enlarging for printing. Ideally you want to work on an image at the final size, choosing the resolution at those dimensions
. When working on something that might eventually be printed out at a very large size though it's not as simple as that, so get guidance from the people where you're getting it printed if you can (some help on this in the links below).
Ideally you don't want to save for print as a JPEG since this is a lossy format; at high quality levels there is very little image degradation but below a certain setting you get characteristic blocks in the image formed by the compression that can be easily seen at large sizes.
BTW, just a technical note I've made before: image resolution is PPI, printer resolution is DPI; very good idea not to get them mixed - we have control over the first, the second we don't
Here are some previous threads you might want to look over which cover some of the same ground:
Incidentally vector images largely sidestep all these issues since they are scalable or resolution independent
, so if saved the right way they're as sharp at 2m as they were at 6cm