Yeah, much like Agent Smith, I too use Thumbs plus a lot for printing (in addition to photoshop).

Usually I don't pay much attention, if any to DPI.  If I have an image which is total of 1024x768 pixels, and want to print it on an 8x10 piece of paper, I know it will be pushing it. I'm getting barely 100 dots per inch on printed paper. With most printers this can look pretty pxelated. Although, with certain printers, the drivers and printer settings have way of getting around even that by adding little bit of printer created diffusuion, so you get a soft focus effect, rather then hard edges pixels.

It also very much depends on the image itself, what is depicted. If it's a complicated scene with a lot of detail which needs to be shown in focus, you want to push the number of pixels as high as you can. If you;re doing a photograph with a soft focus or an abstract with not so much detail, you can get away with a lot fewer pixels.

I've made prints at 100DPI that people wouldn't believe were 100 DPI because of the quality. I've also seen 300 and higher DPI printouts that didn't look very good.

Higher isn't necessarily better. It's knowing the best setting for what you are trying to accomplish that counts more. For me, this came with experience and trial and error. You need to get to know your rendering program, your printing program and your printer drivers. There are settings in all of those that can afect your end result much more then just plain DPI. So much that I tend to be almost completely unaware of DPI settings in my images.

I look at it every once in a while in photoshop when I need to resize the image to fit the paper. Even then, I don't go by the DPI, I just glance at it as it is displayed in the dialog box. I'm always aware of my overall image size in pixels.

Depending on the audience....
Here's what I mean... Where is the image going to be presented? Is it going to hang on the wall somewhere where the closest anyone is going to get to it is 5-7 feet away? How much detail can a human eye pick up from that far away? Looking from 7 feet away, human eye typically can't tell a difference between an image printed at 600 DPI vs. 300DPI. It has a hard time seeing a difference between 300 DPI and 150 DPI (when the printer setting are done right).

Are you doing a piece for a home decoration for someone that is not overly art savvy, or someone who is very discriminating? Are you doing a piece for a gallery or something that will be juried?

Sometimes I need to do an artboard wich will be displayed where people will just glance at it and move on. For those I know I can lowe the quality. Other times, I know I'm making a project map which will be laid on a conference table, and will be studied in detail, almost inch by inch. For those, I know I have to have very crisp detail. There were times I rendered them in several squares and composited them in photoshop.

Also, you need to see based on the coloring and the type of the image, what kind of the file type is best suited for it. Out of rendering I first save at the highest grade, but then I take a small piece and see if JPG, or TIFF or a GIF, and color depth, or indexed color and similar variations in settings don't give me manageable file size, and preserve the detail I need. I really don't have a 'canned' solution for things. I handle them case by case, whatever fits each image the best.  

Just my 2c  HTH

Hi, my namez: "NO, Bad Kitteh, NO!"  Whaz yurs?
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