I had to repair a corner joint between my kitchen and living ceiling (kitchen is ceiling lower than living room) by scraping the popcorn off of the kitchen ceiling and replacing a metal corner bead. The repair seems to have taken and held. Now, what should I do with the kitchen ceiling? Many have advised not to try to apply popcorn to that small section of kitchen ceiling - that they will never match. Should I just scrape the rest of the popcorn off of the kitchen ceiling? Then what? Re-apply popcorn, some other texture or leave flat and paint?
I've had similiar issues and have re-applied the popcorn to good results since my house has popcorn ceilings. You can certainly scrape off the popcorn for the entire ceiling and either re-apply it or smooth it out, but now the scope of the fix has increased.
Basically most home improvement stores sell popcorn spray in a can. @Tester101 has provided a link to one such product.
I can tell you from past experience that spraying on popcorn is not like spraying on paint.
After that it hard to spot and will not be easily noticable unless you are actually looking for it.
Here's a picture of a patch job. The patch is right on the corner that juts out slightly. It came out pretty well. Nobody ever notices it. The texture is slightly different, but I think if I practiced more before applying I could have matched the texture a little better.
No - It will never match the original pattern. But we had similar issues in many apartments where we couldn't just leave a bold spot. So we had to re do that "area" area being keyword here.
Afterwards apply some undercoats to the area that was redone (we did ours with a concrete mix but some have silicone or other types)
Only you will see exactly where the repair work has been done but trust me. Nobody else will even notice the difference because they would really have to know they are looking for something.
Basically applying a similar patter and repainting the entire area will take the obvious repair work out of eye sight. Just don't tell any body because then everybody will see it.
(That is why I hate doing my own DIY work because I always find something somebody else messed up or the tiny shortcut I took that nobody else ever will even know about)