I've got to blow up images (created in Poser/Vue) to VERY large scale (ie billboard size) for an art project. Is there any better resizing software anyone can reommend (other than photoshop's own internal re-scaling mechanisms)? For instance Perfect Pixel? Is this any good? Any advice gratefully received. JAMES

Attached Link: Art for Billboards

Here is a forum thread from a graphic arts site that has some good information.  Maybe you will find it helpful.

I hold as a rule of thumb that A3 size (42cm x 29.7cm) at 300 dpi is the largest you need, ever. When sizes go up, the dpi goes down. The best reason for this is simple, prints that size will be looked at from a greater distance. And most production methods for largers sizes do not actually use any more dots per inch, so it is wasted space and computer power. For enlarging I use Genuine Fractals, but have used PhotoZoom too. Actually, enlarging in Photoshop, and trying different interpolation methods might be just as succesfull. I am not seeing huge differences in quality. Ideally you should start with the largest originals you can produce. Enlarging always involves 'inventing' (interpolating) new pixels, so the more pixels have to be created, the blurrier the end result will be. Enlarging beyond 400% will really start to degrade the end result (it will start to look like a water painting more and more - but that does not have to be a bad thing). So: large originals and a resolution that goes down after sizes that surpass 42 cm (16.5 inch). Some people insist you should enlarge in steps of 10% for the best result. But that takes a lot of time. And I don't think anyone will see the difference once the billboard is out there.

I've prepped an image for a billboard - and that was a REAL learning experience! I thought I was going to have to make enormous files for them - nope...

The printer told me that highest that would possibly be printed by a billboard company would be 36dpi - that's only for SMALL boards like 10x12ft.

The one I did was going to be printed at 12dpi as a 10x20ft banner - that was only going to end up being 1440x2880! What helped with my prepping was that only about 2/3rds of the image was going to be photographic anyway - the rest was solid colors and vector graphics - I just set up the file in the exact format it was going to be printed and filled it accordingly.

When they print boards for the sides of buildings, or extra-large signage you drive by on highways, they typically print 9dpi! Not kidding!

It doesn't have to be huge - it really doesn't! Ask the printer what is going to be the output - and they don't play the games that publishers do (demand it be 300dpi for their output size when they only print 150 lines per inch!). They tell you exactly what's going to be printed because THEY don't want to deal with uselessly enormous file sizes.

Good luck-
-Lew ;-)

Attached Link: http://www.renderosity.com/mod/forumpro/showthread.php?message_id=2636758&ebot_calc_page#message_2636758

Look at this previous thread, particularly my post to be specific from April 1, 2006.

the 50% size has twice as much dpi, if i zoom in i won't notice the pixelation. the 100% size has equal the dpi, if i zoom in i wil notice the pixelation. both will have the same output dimentions. Instead of sampling one pixel from a 150 dpi images (to produce a colour) it samples four pixels from a 300 dpi image. People will be viweing this image from 14 inches away more or less. if you held a ruler in front of your face, about 14 inches away and measured a bill board , you can imagine that it has a higher dpi from the rulers point of view.

btw this is ONE halftone dot (with a grid) how many would you like per inch, so that you saw an image instead of a collection of dots from the point of view you have?