Optimum Pixels Per Inch for Canon Pixma Pro 100

[aajax]

Some discussion in another forum by very experienced photographers many of whom are familiar with Canon equipment has suggested that by preparing image files with a resolution of 300ppi the Canon driver (NOT just for my Pixma Pro 100 but for lots of Canon printers) will produce the best possible results.  While it is admitted that this does NOT always produce a discernible difference sometimes it does.

I think the idea is that the printer driver is always (?) going to scale the image to 300ppi and that its' method of doing so might NOT be as good as can be achieved through other means.  I've spent a good bit of time hunting through Canon supplied documents looking for some explanation of this phenomenon but with NO luck.

Is it possible that any of you might be able to refer me to such documentation?

[rs-eos]

What is the intended viewing distance of the printed results?  If up close, higher ppi/dpi will be better.  But if viewing from a further distance, lower ppi/dpi will be just fine.

What are the phyical dimensions of what you'll be printing?  e.g. say you need 300 dpi and will be outputting 16 inch by 20 inch prints.  You'll need a minimum pixel resolution of 4800 x 6000 for that.

I would imagine that to avoid any scaling whatsoever in the printer, using the above example printed at 300 dpi, you'll want exactly 4800 x 6000 pixels.

[aajax]

The maximum size print that my Pixma Pro 100 can do is 13x19.  Therefore printing 18 inches wide would require 5400 pixels to get to 300ppi (which I gather is the same as dpi in this case).  Right now that's a little more than my camera produces.  This has caused me to start shopping for a better (higher resolution & likely full frame) camera.  When seeking some advice on that the discussion drifted to some other topics which included printing.

This lead to the idea that there is something special about precisely 300ppi for Canon printers (happens to be 360ppi in the case of Epson).  These professionals are suggesting that printouts should be sized precisely at 300ppi for best results on Canon.  The idea being that this is true even if the image needs to be scaled down (i.e., reduce number of pixels).  If I understand correctly the idea is that the driver will try to either up or down scale the image to 300ppi and that a better job of that can possibly be done using post-processing software, which includes lots of possibilities, rather than rely on the driver.

[jrhoffman75]

Jeff Schewe, who is considered an expert on digital printing, and was instrumental in the development of the Lightroom print module discusses this topic in his book "The Digital Print".

He discusses the native print resolution and printer resolution.

For perusal here: Finding the Right Print Resolution - Digital Photo Pro