Hi, Let's say I wanted to render a picture to be printed as a poster, say 24" x 36". I imagine the render setting would need to be 300 dpi, but what about the size of the render itself? Also, I know there would be a vast difference between how it looked through my screen and on photo paper, so what would I have to do to retain as much of rendered appearance as possible once printed. I imagine it would require a certain amount of coloring and brightness/conrtrast correction in post work..or would saving it from Painter as CMYK do it for me? Better yet any good URL's where I could learn about printing, or printing services who could do it for me? Varian, I'm looking in your direction. ;) Thanks a bunch, Mike

24 (inches) x 300 (dpi) = 7200 (pixels) 36 (inches) x 300 (dpi) = 10,800 (pixels) I learned that equation from Karl, here in this forum some while back, and it's been very helpful! :) I'd suggest sticking to RGB and yes, use photographic paper for the best result. As for printing services, I really don't know! I received some spam a couple days ago that might help, but I haven't checked this place out, so use caution: http://www.PrintOnClick.com I think you could print it easily enough yourself. The hardest part would be having a printer that will handle the size of paper you're aiming for. But I'm not a print expert around here. So hold on and wait for Karl and Laurie and... ! :)

If you're doing the printing, stick with RGB and make sure your monitor is calibrated properly. If you're using a service bureau, they will tell you how they want the file.

Hi Mike, Varian got it right. But, as Jackson said, you should talk to the people who are going to print it (if you're not doing it yourself) to find out what works. The requirements can be quite different depending on the process used. If it's an inkjet process, then you can probably get away with 200 dpi (or even less) without noticeable degradation in quality. It is worth finding out the actual required dpi because 200 dpi vs. 300 dpi will cut the render time by...let's see...4/9...so less than half the time. So, if a render takes 2 days instead of 5 (which it might at this size), that's a big difference.

Oh yeah, if the printer tells you it's an inkjet capable of, say, 600 dpi, don't confuse this with the required dpi of your file. The printer dpi represents how accurate the printer can spray inkdots on the paper...but many inkdots are used to make a single pixel of accurate colour..therefore, your image dpi (in fact, correctly called ppi...pixels per inch...you will see this if you use Photoshop) will be less than the printer dpi.

Hey thanks all, I think I'm starting to understand this a little more. I don't have a printer capable of that size, but there are places around here (I found out on the phone since I first asked this) that could do it. I think on Monday I'm going to go talk to someone at this one place and see what they would recommend. I have a friend (more like a work acquaintance) who really liked that "Ghost in the Lagoon" picture that I put in the gallery here, and wants to buy a poster-sized copy of it to frame. :) Obviously I would need to redo it and get it ready for such a thing-- good thing I saved the scene file! I don't even have any idea how much I should charge. shrug Thanks again!

If it's less than $150, you're cheating yourself. IMHO. :)

You'll get a real good idea what to charge after you find out how much the printer is going to charge you. It may not be cost effective unless you feel you can sell many prints. In printing, the big expense is in the initial setup; additional prints aren't that much. Good luck.

One rule of thumb you might want to keep in mind. The larger the original is the lower the dpi requirements would be to retain details. The smaller the original is the higher the dpi required because as its enlarged it will lose definition more quickly with a lower dpi. If definition is important then make your original as close in size to the anticipated printed product as you can. Be willing to give up dpi if you have to. Its the ratio of size difference between your work and the printed product which is most important. Remember most programs create fairly small pieces because normal screen sizes are in reality quite small if directly translated into actual print sizes. Most photos for instance are between 72 - 150 dpi with some occasionally going as high as 300 dpi. It would be very rare if it exceeded 300 dpi. Also most commercial printing, (dependent upon the process of course) is printed at a much lower dpi then you might expect. Because of the layering of ink, used to create the various color shades and blend them, a higher dpi sometimes works against you when translating to commercial printing. Again its the ratio of difference between the original work and printed product which is important. Most definitely talk to your printer before you make your piece.

Mike, I've done a LOT of print work, mostly with Bryce and Photoshop, but the concepts are the same. As you know the print world operates off of subtractive color space, meaning the less color there is, the brighter and closer to white it becomes. A monitor is additive, so as color is added, it becomes closer to white. Typically, additive devices use RGB color space because the gamut, or color range, is so huge. It's just about as close as you can get to the visual range. Obviously monitors use this principle very easily, because they are constructing colors using light. With printing, CMYK is most often used (Cyan, magenta, yellow, black). When you take an image and convert it to CMYK, say in Photoshop, it's often a disappointing result, but this is how it more often "used to be done." Typically, the best thing to do nowadays is send the RGB file to the printer and let it sort it out. The printer will do a better job than photoshop, in most cases, at getting better gamut ranges out of your work. However, this sometimes doesn't work. I've had a few images with extreme gamut ranges in sky -- particularly in the blue family. Because this is CMYK's weakest link, so to speak, the image after it was printed had severe banding, or obvious changes in color as opposed to smooth transitions. I've had tremendous luck with Iris prints. They are typically expensive, but gorgeous. For my own use, I have an Epson 3000 and seriously, aside from the slightly smaller print size, I can't tell the difference from the Iris unless I'm up real close. The only other thing is rendering at that resolution. The pixels that Varian gave you are totally correct, but as you know your render time will likely be absurd. If you need to resample, of course Photoshop and the like can do bicubic resampling without a problem and get good results. But I've been using Genuine Fractals, and the results are amazing... basically it allows some really amazing results... http://www.genuinefractals.com Finally, 300 DPI is a good number to start with. But it does depend on the output device, and what it's capable of. To a degree, it largly depends on the type of paper you use. Here's a nifty article on that: http://www.techcolor.com/help/linescreen.html The typical rule of thumb has always been: take the linescreen, and go from 1.5x to 2x that in DPI. So for 150 linescreen, you should think about 300 DPI. Anyway, I've babbled here long enough, just thought I'd give some feedback! -Brian

As Brian said, most printers work in CMYK. We do alot of print (using LightWave) and work entirely in RGB. When we send our images to a printer we also send a color (match) print along with it so that when they color correct (from RGB to CMYK) they have accurate color samples to work with and can get the colors almost exact - of course that depends opn the printer! Some printers won't charge you for color correction, others will. Best of Luck!

Wow, tons of great info in this thread. Thanks, everyone! :)

Yeah, no doubt. Thank you, everyone, this is great stuff here. :)