Leon S wrote:
My question is the Canon I am looking at prints 9600 dpi. Most other printer print 4800 dpi. A good Epson will print 5600 dpi. I shoot a d700 12 mp Nikon. Will the 9600 dpi print more detail for me than my 4800 dpi present Canon or for that matter the 5600 dpi Epson? Secondly the 9600 dpi Canon also uses a gray ink. Will that mean I will get better color and black and white out of it than a printer without the gray cartridge?
You've done a very good job of finding the significant questions to ask!
First, Gray ink (and other odd colors too). The various shades of black will mostly provide better BW prints. But they'll also help with the dynamic range of color prints. Other colors add slightly to the "colorspace" the printer can attain. A simple CMYK printer cannot generate some of the colors within sRGB or aRGB as well as a printer with two or more added shades. Different manufacturers have made printers with different added colors. (They are all very good too.)
Printer resolution is hard to understand. I do commercial printing, with Epson printers, and will use those as examples. Canon and HP printers vary in the exact numbers, but it works the same.
Between manufacturers the biggest difference is how many pixels from the image will be printed on a horizontal line. Epson uses 360 PPI, Canon and HP use 300 PPI. Be advised that various commercial printers from Fuji, Noritsu, Durst and so on use values from 300 to 406. Also note that Canon and Epson both have high resolution modes that manage 600 and 720 PPI respectfully.
For images, you can ignore the high resolution specifications. The only Epson printers that can do 5670 DPI are
consumer grade printers. Resolutions higher than 400 DPI are great for text and line drawings, but are not for photography.
The Epson 4xxx, 7xxx, and 9xxx commercial grade printers are all intended for photography (the 7xxx and 9xxx cannot autofeed sheet paper and are actually only useful for roll paper). The maximum resolution they print at is 2880 DPI. They have 8 ink colors and 2880 DPI is 360 PPI (each pixel is an 8x8 matrix with as many as 64 individual dots of ink).
If you buy a printer for photographs only, 2880 DPI (or 2400 from Canon and HP) is all you need or want. Even then, to get greater speed you'll probably end up printing all but the most critical work at half that! Only if you print text, line drawings, graphic arts do you have a need for 600/720 PPI that requires 4800/5670 DPI.