How can i change a work in Photoshop from 72dpi to 300dpi easily?

i work on a 72 dpi in photoshop, after knowing that 300dpi is the recommended value for printing, i have to change at least 5 works to 300dpi....



so can i just simply open the file, click image | image size ...and change the 72 to 300?



or rebuild everything from scratch! (since i still have the files with me).....will these two methods have a drastic and observable effect/improvement?



or is there still an easier way yet without sacrificing quality?How can i change a work in Photoshop from 72dpi to 300dpi easily?
Resampling from 72 to 300 DPI won't work well. The image will become pixelated, and if you try to smooth it out it will just become blurry. The problem is you need to make pixels where there are none, so the program is forced to expand on existing ones - you need the detail in the first place.



If you want good quality print you will need to rebuild the file.How can i change a work in Photoshop from 72dpi to 300dpi easily?
Sure you can, just change the 72 to 300 dpi and resave the image. on your screen you cannot visibly see the difference, but if you saved at 72dpi it would not be print quality. That is where you would see the difference.