dpi res. where?..how ?....

[salf]

Well, i dont know if this shoulda been posted on the VIZ section, but here it goes:

 

So far ive only made small images (compared with some images out there, mine are small) of projects to either architecture students or architects, that print the images at "regular" print sizes, mostly on regular plotters, the standar 90 cm page size.

 

So my images where made mostly JPG 2000 X 1500 px maximun, and thats it!

 

But now, i will probably gonna do images that will be printed in various sizes for promotional material, im not aware of the maximun size they will print out, so i dont know if theres gonna be only a whole page of the local newspaper page size, or a 2 mt x 1 mt banner, or even a 15 mt highway billboard.

 

Actually i dont know if im gonna do the job, since i have to send my work estimate budget to compite with others.

 

So, i was asking around people on the advertisment field, and considering also my PC system, im gonna do my budget with images 3000 px X 3000 px at 100 dpi as the maximun file size, (either JPG or TIFF), so they decide based on that, if theyll need a bigger size, then they shouldnt hire me.

 

Well, so, now that i found out that 100 dpi is a good resolution for the images, i went to VIZ to run a test render, but i have no idea where to set the dpi resolution.

 

When we do renders we only set the file size, and at the end the quality in %, but theres nothing about "dpi" on the RENDER SCENE dialog box.

 

How to set the "dpi" on VIZ?, maybe im asking something incredible stupid, but im really lost with this one.

[Chad Warner]

quick math is output size (in meters or inches) x resolution (in dpi) = rendered image size. So, an 8"x11" print @ 100 dpi would be an 800x1100 pixel image. That would be my rendered image size (numbers entered into the "output size" dialog box.

 

Viz also has a print size wizard that you can input these numbers into, and it will automatically adjust the output size for you. (under rendering, print size wizard)

 

-Chad

[salf]

mmmmm.........ok.....but......the thing is that i dont know what will be the "print" size theyre gonna need.

 

So ive been told that I could just set 100 dpi as resolution, because with that dpi , others could double it to whatever size they need without losing much resolution. So lets say that 100 dpi gives me more liberty in printable sizes, of course the more dpi the better, but most of the pple i asked work with 100-120 dpi.

 

Maybe im just pretty damn confused (like when in maths classes on highschool), following your example 8" x11" at 100dpi is 800x1000 output size.

 

So if i say that i can only produce images 3000 x 3000 pixels, that means that the best printable size for the client is 30" x 30", at major sizes like 40 or 50" he might not notice a major drop in the print quality, but maybe if he deicedes to print out a 100" x 100" billboard, my image will not be enough?

[Chad Warner]

That is correct. My general rule of thumb is 150 dpi for anything 48" and under, 100 dpi for 4'-8' and 50 dpi or less for anything above that. That means that for a 24"x36" board, I end up with a 5400 x 3600 pixel image. With that resolution, I can print a little bigger if I have to, but with a loss in quality.

 

-Chad

[salf]

thanks a lot.

 

Altho I dont get your "rules of thumb", you say:

 

48" or less = 150 dpi

 

4' - 8' = 100 (so you reduce the dpi if the print size will be bigger?, shouldnt be the other way?)

 

And a last thing, whats the bigger print size you had to render out?

[Chad Warner]

No....lower dpi for bigger prints, because bigger prints are generally viewed from farther away, so they don't have to be as high quality. Largest image I have rendered is 9600 x 4800 pixels, which was region net rendered.

 

-Chad

[Elliot]

Guys, this is a very sensitive subject with me.... and equally confused. I am in the process of trying to achieve a high quality brochure. I want photos that look very sharp and crystal clear.... Like the old LIFE magazine of the 60's.

 

What DPI setting will do a high quality print. The brochure will be on letter size page. One printer told me he wants the originals at 600 DPI. Which is fine, the only thing is that I will have to send him my hard drive on FEDEX because the images will just be to big.

 

I use MColor from Motive.... Great little gadget.... However, the file sizes are making my computer... too squeal with pain....

 

Is 300 DPI good enough. I have done all kind of test with different printers.... I really dont notice much difference after 300 dpi on a half page photo.

 

 

Thanks

Elliot

[Jeff Mottle]

Round and Round we go. I've posted the thread where I tried to explain all of this as best I could in the Tips and Techniques section. I think I wrote this about 2 years ago, but it's still good. If there are any errors or corrections let me know and I will amend the post.

 

http://www.cgarchitect.com/vb/showthread.php?t=5759

 

Elliot: 600 dpi on a letter size page (8.5 x 11) is hardly reason to FEDEX a hardrive. That is only 5100 x 6600 pixels. A tiff file zipped up should not be more than about 50-60 MB at most. You could use FTP for that file. I don't know of any image ever that should require that. As has been mentioned already, typically the bigger the sign/poster/billboard get the less resolution capability the printer has and consequently the smaller the image size.

 

Anyway the link above should answer everyone's questions and then some.

[Elliot]

Jeff,

 

Thanks... Yes you are right about the size.... The brochure will have 12 pages and many many photos.....

 

Glad you made it back from that "awful" meeting at the strange bar.....!!! My wife is always thinking about my safety and would not allow me to risk my life in those kind of business enviroments.

 

Elliot