I know you can resize pictures and what not...but from my experiences going from smaller to bigger is nothing but blurriness and crap...which makes sense. But how do people take a 4x6 picture and enlarge it to a poster sized image. Is there something I can do in PS or is special software needed?

thanks,
Rich

There's no good way to do this BUT you can get close if you gradually increase your image size by 110% repeatedly.

It helps to make an action for this.
It also helps to have a high quality picture to begin with.

But I've used this method to take a wallet size photo to an 8x10 before. Worked pretty well.

Its a matter of pixels. A 400x400 version of a 200x200 original has four times the pixels. An 800x800 version has 16x the original image. Basically, You can't enlarge information that simply isn't there. (unlike on csi where really crappy low res distant focus security images get blown up to 8x10 glossies) A one pixel glint in an eye is now a 16 pixel blob in a 45 pixel dark spot. See?

A few plugins work better than the default PS bicubic interpolation. I've got decent results out of "Alien Skin Blow Up" and pxlSmartScale.

What about scanning the image at an insane DPI? Then using rashdog's upsizing method.

Up scaling you want image size set it to bicubic smoother...

Image > image size, check... bicubic smoother change the dpi to 300 for posters / print

also if you are intending on printing it out change the colour mode to cmyk



Pixelation is annoying at best so ya reallly want to be getting your source at a large size

I tired this with 600 DPI and it seemed to work alittle better...but it turns out i dont need to make them to much bigger than the original....thanks for the info guys/gals.