Hi, this is my first post about printing issues.
Right now I'm using the next formula to calculate the resolution for "small" format prints (i.e 21cm x 29.7cm):
Final res = lpi x 2 x ampliation/reduction factor (in %)
This way I'm getting reasonable values like 600dpi.
If I use same above formula for Big Formats like billboards, photo-calls etc I'd obtain incredibly huge file sizes (and my PC would get knocked down). So: How can I calculate/Know the final Res of my art knowing beforehand the final size of the art work (billboards and so on) ??
Any rule/formula/tutorial-link ??
Thank you very much in advance
I think you're misremembering curt. i believe phos and bob l have said if they're going to be large images viewed at a distance the ppi can be much lower. 100 or less. i could be wrong, but i don't think so. ;)
one of the billboard guys is sure to chime in soon to clear it up.
300 ppi is way, way too high (so is 100). 100 ppi for posters viewed across a room. Across the highway, and I would think 50 ppi would be a ridiculous, gonna-piss-off-my-vendor-but-what-the-hell number.
Back when I was doing them, our big printers were pretty slow, finicky and cumbersome, but still cranked out some pretty amazing images. And the RIP took our work, rasterized and resampled to 18 dpi, sometimes 36 dpi.
We generally set up our Photoshop files at a scale of 1/4 in. = 1 ft.
Computers are faster and more robust, RIPs are better, and the printers are a lot more sophisticated.
As has been advised: Talk to your service provider.
I did a 14 by 40 foot billboard at 10 dpi, and they said that was more than
Truth is, for most billboard viewing, 4 dpi would be plenty.
LED billboards and giant TV screens often use 1 LED/pixel per inch, or even
..5 per inch. In such cases each pixel is simply a tiny bright dot in the
middle of a two inch square. As you get close to an LED display, the dots
will suddenly fail to fill the pixel area, and the image will all but
disappear (to you). I saw an LED TV in an airport the other day, maybe 5 x
8 feet, whose resolution seemed to be about 5 dpi, falling apart at about
One full size billboard manufacturer claims VGA resolution. That's 600
pixels wide, right? At 40 feet, that's 15 dots per foot, or 1.25 dpi.
So really, on a billboard that big, there's no reason to ever go above 10
dpi. Look at what a tenth of an inch is, and imagine it on a billboard
fifty feet in the air.