Adding dpi?

[Tittan]

My camera (Pentax K20D) shoots RAW in 240 dpi, but my client wants 300dpi. What happens to the photo when I use Photoshop to "blow it up" from 240 to 300 dpi? Will the photo be messed up, or is it possible to pull it off?

And on a side note, does anyone know if I can shoot RAW in 300 dpi on the Pentax?

[teaking]

I think its probably best to understand what DPI is, in fact as pointed out in an earlier thread its actualy PPI as in pixels per inch. And it is a physical attribute of an image that occurs in direct partnership with image Width and Height.

What actually happens when you print at different sizes is that the pixels are fit in to that image size so a smaller image has more pixels in each square inch compared to a large image of the same picture.

So all you really need to pay attention to is the pixel height and width and what size you want to print at. With a bit of math you can work out your maximum image size if you wish to stick to the 300PPI restriction. just divide the pixel width and height by 300 and thats your maximum print size in inches at 300PPI.