Render size

[skyview5]

I have a question about render sizes. (terragen classic) I want to render an image and have it printed poster size, which is 20x30 inches. Do I just render it at 3048x2032 or should i double the size and then lower it in post work to poster size? I am confused about the image size for widescreen monitors as well. On my screen, i use 1280x768, and this gives me a full screen, but is this size considered widescreen? or should i use the setting that my laptop has, which is 1440x960 or so. Is there a size that i can use that will allways give me what i am looking for (look good on any screen)? any help will be appreciated, or any links to some threads allready posted on this subject. Thanks.

[Simius Strabus]

Consider this to make a good poster:
You need to do around 300dpi, so a 20x30 inch poster would be rendered at 6000x9000 pixels.
To prevent a grainy result, I would not recommend going below 200dpi.

[skyview5]

Thanks for the reply. When I render at 6000x9000, i look at the pictures properties, and it says its only 96 dpi. The quality settings were set low to make a fast render, not sure if it would change the dpi or not raising or lowering the quality. How do i raise the dpi enough to ensure a good clear poster?

[skyview5]

read this on another site: print size x printer resolution = render size in pixels
                                 so... 20x300(dpi)=6000
                                         30x300(dpi)=9000 = 6000x9000 just as you said.  I am assuming the print shop deals with the dpi or ppi themselves, and i just render with the above formula?

[Simius Strabus]

I'd go for the 300dpi resolution, just to be on the safe side. Also, try some higher quality settings.
In TG2 I use a detail setting of 0.8 to 1 and an anti-aliasing of 3 to 4. Not sure what settings to use in TG1.

At 96 dpi your poster would be 62.5x93.75 inches. Kinda big...
How did you get the dpi properties? Since dpi is a relation between image resolution and actual printed size I'm puzzled
how/why 96dpi showed up. It may be related to an installed printer or something...

[skyview5]

To get the dpi of my rendered scene, I rendered a scene, saved it and right clicked my saved image and click properties, then sumary, it says 96dpi veritcal resolution and 96dpi horizontal resolution. That is with a 6000x9000 render from terragen. So I wonder, if I render a scene at 6000x9000 and bring it to a photo place to have it made poster size, will they say it will has a high enough dpi to get a clear picture, or is there a way to change the actual resolution in terragen?

[Simius Strabus]

It will be the right res(6000x9000) for a 20x30 poster. I've done it before at 9600x5400for a "wide screen" poster. Was 32x18 inches. Complex scene, took over 2 weeks to finish...

[Oshyan]

DPI is meaningless until/unless you print something. The "DPI" in your file is just a simple number in the meta data. What matters is the resolution of your image and how that will map to a 300DPI print. The above numbers are correct for a 20x30 poster as far as resolution, so as long as your render is that resolution, you can print at 300DPI and you'll be fine. It doesn't matter that the rendered output file doesn't say "300DPI" in it. You can easily change that (and should) before submitting for printing, just make sure you do *not* resample the image; all you want to do is change the DPI. You can verify it's correct by looking at the printed size in inches that you get after changing the DPI - if it's higher than 20x30 look for a "resample" check box and disable it, then set your printed dimensions and DPI correctly.

- Oshyan

[Kadri]

As Oshyan said and you can look here too.
http://www.planetside.co.uk/forums/index.php?topic=10040.msg104660#msg104660
This is a common problem around that people get confused about.
Especially PorcupineFloyd's  link could be very useful.

[skyview5]

Thanks everyone, the info helps a lot. Can't wait to see my render printed poster size!!

[Simius Strabus]

Have you uploaded your image to the image sharing section? Like to see it.

[TheElectroKangaroo]

I always render things at four times the size I want, then resample the bitmaps down to the required size.

[skyview5]

Here is a small copy of the image I rendered. I could not upload a high quality version due to my crappy dial-up connection. opinions welcome!

[Simius Strabus]

That looks realy nice. Looks like the bottom of the lake is glowing. 

[skyview5]

Thanks. It took forever to render.