The required, or desired, resolution depends on the nature of the artwork.
It is important to make a distinction between pure vector artwork, that only gets rasterized in connexion with printing and where you just leave it to the printer, on the one hand and raster artwork/effects on the other hand where the resolution is inherent in the artwork.
It is also important to make a distinction between the crisp parts such as type/text and line art and woolly parts such as colour transitions, photos, and the like. The former kind requires a much higher resolution (which may be 2400PPI/DPI) whereas the latter may be lower than many believe (instead of 300 PPI/DPI the requirement is normally 1 to 2 times the screen ruling in lpi, and with stochastic screening you may may choose between a superior quality or a lowerrequired resolution), and both depend on the printing equipment and the required/desired end quality.
Text and line art as high as their equipment goes or is relevant for the kind of print (which may be 2400), if not vector artwork (where it will be set by the printer).
Photographs at 1 to 2 times the screen ruling in lpi (which may be as low as 45 or as high as 240 (or even 340 for Stochastic Screening) depending on their equipment and the kind of print).
In other words different resolutions for different kinds of artwork (horses for courses).
I understand different resolutions for different artwork. I guess I was not clear.
Specifically what I am trying to figure out, is what the difference is between 300dpi and 2400dpi in the sense of a finished product.
Ie, if I send a 10 page catalog to a printer at 300dpi resolution will the finished product sent back to me look the same as if I sent the file in 2400dpi?
IF there is a difference in the product, how much of a difference is there? Is it a night and day difference? Or only marginal? OR is there no "visible" difference at all?
I've always sent files to print at 300dpi and have always been happy with the results. But, am I missing something by not sending files in 2400dpi?
I don't know where you could get that information.
You could go to this link: http://printplanet.com/index.php and post your question in their Forums. This is the best place to ask questions like that.
This would be a start:
When you're talking about 300dpi art, in reality it should be 300ppi (pixels per inch). Below is a quote from that Scan Tips site:
Printer ink dots and image pixels are very different concepts, but both use the term dpi in their own way (dots per inch).
Inkjet printer dpi ratings refer to printer ink dots (the four colors of ink), which is NOT AT ALL the same thing as image pixels. These are such different concepts that some people think we should reserve the term dpi for those inkjet ink dots, and reserve use of ppi only for image pixels. Not a bad plan, except that this view fails to recognize real world usage.
In the quote above, when they say "Inkjet printer dpi ratings", it applies also to offset printing presses.
So, recently I ran into a situation concerning print resolution. Now, i've always output my images at 300dpi to professional printers.
You have never output your images at 300DPI. Professional printers do not use that low of DPI.
You are confusing PPI and DPI. These are very different things and can be googled/wiki'd for more info. You should use 300 PPI. The printer uses 2400 DPI.
As others have already mentioned; there are two different types of resolution: image resolution ( i.e., 300ppi ) and output resolution ( i.e., 2540dpi ). ReneG got it right. The print vendor is probably referring to 2400dpi RIP ( output ) resolution. Try to refer to image resolution as pixels per inch ( ppi ). This is a very technical issue that few people truely understand. The ideal resolution for a 300ppi image is 5080dpi. This leads into an issue regarding levels of gray, which I will not go into with this small space. Most modern day RIP's ( Raster Image Processor ) output at 2540dpi and 5080dpi. You might find a laser printer with an output res of 2400dpi.