Poster sized images

So I'd like to make some posters - sized 27" x 40" (movie poster size)... the problem is, all the images I can find (stock photos) are 8.6" x 13" at 300 dpi or even as low as 6 x 9" at 300 dpi.

How do I go about making these large enough without sacrificing much quality... they still have to look professional when printed.

 

you can do it at photoshop.
try also Genuine Fractals program.

 

You can't replace detail that doesn't exist I'm afraid. Photoshop can make some educated guesses but can't make high-res files out of lo-res images.
You could try artistic effects, halftoning or other effects.

 

you can do it with photoshop.if you use another program, you can save it big pixels with pohotoshop then you paste it in your program. it will be good quality

 

Photoshop doesnt have the ability to enlarge images without losing quality, image tend to break when enlarged.

 

Hmm, I found this article that says using staircase interpolation at 10% increments is fairly good in CS2 (CS4 is what I use): http://www.pdnonline.com/pdn/cp/olympus/technology/article_display.jsp?vnu_content_id=1003550548

Also they recommend Blow-Up by Alien Skin - anyone familiar with this?

Do you think the printing company would have the ability to blow it up better than I would?

 

Im no pro, but i think if you stretch it it shouldnt make TOO much pixelation, Photoshop auto fixes pixelation to an extent, your going to loose some quality but i dont think it will be as much to ruin the poster. Or just go on stock websites, Paid ones for better results. www.istockphoto.com and the likes.

 

u can also do it by Xara , open your pic and resize it its easy and without losing quality

 

a letter (8.5 x 11") sized image at 300dpi can be blown up to any size, i use to print wide format some 65feet by 38feet at 5dpi, i tell you, it looked great from the road, its all about distance

 

according to me u can use xara