I worked on few exterior images. Now client want to print those images on hoardings on site. Hoarding size is 60’x100’!!! which is roughly 18m X 30m . I dont know what size images i can maximum render & later what need to be done to make it printable on such big hoarding… I am stuck 
I’d say around 6-8 thousand pixels on it’s largest side. With the usual DPI thing for print, the further you have to stand from the print to be able to take it all in, the lower quality you can go. For example if you have a magazine style print, you need it to be around 300 dpi for really good quality since you hold it about 18 inches from your face. For an a2 photo print you’ll have to stand back a bit further from the image to see all of it, so you can use 150 or 200 dpi and still get a perfectly sharp result. For large images on bus shelters which might be 5 feet by 8 feet you can likely use 50 dpi. For something as big as a huge poster you’ll be standing a long way back from it so you’ll never see any pixelation or dots in the print - around 6000 pixels is about the largest I’ve ever rendered an image and it’s been fine!
In my area we usually use 10k pixels either way to go on bilboards… 7-10+ depends how big they want. They then print it at usual 70 DPI and all is well…
I’m not as technical. I see a lot of my work on construction signs, and 11x17 @ 300 dpi, usually works. I have never had to render larger than that, for anything I do. If something is large, it’s usually viewed from a distance.
And this clears all! Thanks!! I will render in 10k lets see how it looks after printing.. pretty excited, 1st time my work going to get printed 
Time ago I succesfully rendered a 18k wide image; just remeber to check the “Render to V-Ray raw image file” option, otherwise you will probably go out of memory.
All you have to do is to send job to backburner and tell it to TILE THE IMAGE. Specivy how many tiles you want and u can render even 30k image without any problems… and all passes will be there :]
to put another way - an A4 render at 300dpi is LARGER in pixels than an A1 render at 100dpi. It’s like John said, the further away you go from the print to be able to view the entire thing, the less the dpi needs to be.
That being said, hoarding is slightly different, because people walk right by the hoarding without standing back to see the whole thing
yes but a hoarding is printed on a litho printing press and gets halftoned
halftone is where it breaks the image into printing dots
the halftone dot screen is measured in lpi (lines per inch) (though I guess there must be lp centimeter as well)
ok : a very high quality brochure or art print will use a screen of 400 lpi - you don’t really get any higher than that
a newspaper will use 200 lpi
old black and white newsprint maybe 80 lpi
a hoarding poster will use c. 30 lpi
theory says you need 1.5 times of pixels per screen line
(actually theory says x2 - but practice shows even x1 is fine)
do the maths… but you never need 18k output for print (maybe a 100 foot wrap around building site image could use that)
and forget “dpi” it’s irrelevant and a red herring
So, how does MAX, or Photoshop interpret LPI?
I assume that when you say ‘pixels per screen line’ you are refering to PPI? I’ve personally never encountered PPI dropping below 1.5 x LPI, but even if a conversion of 1x was enough Prateek’s dimensions of 30m x 18m would require an image of 35433 x 21260 at 30 PPI/LPI…
The lowest I’ve ever been asked to (or more accurately, been able to get away with) on large format printing is 50 PPI - a 96 sheet billboard at that size is 23’000+ wide, so I certainly qouldn’t say you ‘never’ need 18k output.
I’ll admit that more often than not you can get away with much lower resolutions than these but I’ve also seen some absolutely shocking billboards where pixels have been printed a couple of inches across, so it’s worth checking you’re working to the correct size
35433 X 21260!!! thats a jaw dropping figure!
Honestly, I doubt you’ll need to go anywhere near that high
I’d stick to 10’000 as your absolute maximum. If the client or their printer demand a larger size, blow it up & run a median filter over it in Photoshop. You can always fall back on the argument that a top of the line Hasselblad/Phase One camera backs have a maximum resolution of 10’000 pixels (although I have had to stitch multiple shots from these to make a monster billboard ad before)
I had a job last year… my final render was 18k big @_@ the detail wes epic at 100% =D
pic link
http://www.andersonhopkins.com/artists/79/tim-kent/images/115/AUTOMOTIVE-1/4071/Mini-Cooper-GmbH
How are you guys rendering such large graphics? I mean, how many machines, and how long? If I actually printed a 24X36@300dpi, it would take a week+. I would have to render at 7200x10800.
I now trying to put one through BB at 4096X2458, on 6 workstations, and it going to take 2 days.
Heya
Well I rendered it on one 2x Xeon E 5530 not overclocked back then and 24 gb ram… It took around 10h to render it. At 10k+ resolutions AA changes and a lot things works differently… Atm I’m rendering car layers it takes 10min per 10k render so its all down to how well you can set up render…
I guess it’s totally dependent on what you are rendering. A lot of displacement, and high poly trees, are resource hogs.
I’ll be honest, when I see most people’s render times on the forum my jaw falls through the table. 99% of the time the minimum we render things is 8’000 at the longest edge and I would be extremely worried if the final render, including any channels/effects passes took more that 8 hours.
In terms of hardware there are two of us here, we have 5 identical machines (i7 x 980 3.33GHz, 24 GB ram), two machines each and one spare running as a license server and render slave. We try to render things overnight if we can but if not we’ll divide our renders between those 5.
I now trying to put one through BB at 4096X2458, on 6 workstations, and it going to take 2 days.I actually cannot even imagine having to wait that long for a render that size. Even if it had displacement, caustics…etc. That seems insane to me. What power are the workstations you have rendering it?
I have 6 i7’s with 12Gb of ram per machines. I think they are clocked at, or around, 3HGz
they don’t..
it’s nothing to do with Max or Photoshop - it’s what happens when an image gets halftoned at the printing works
(or at the digital print stage)
in fact Max doesn’t really use dpi either - it just uses pixels and outputs an ‘x’ number of pixels wide file.. whether its 2dpi or 200dpi it’s an identical image
- you just might need to scale it differently in your page layout program
[sorry - I just think it’s important people understand pixels, dpi and lpi]