A Site for Photographers by Photographers

Community > Forums > Digital Darkroom > Printing>Technique > Best Print Resolution for...

Best Print Resolution for Epson Printer - is it really 300 dpi?

David Williams , Jul 30, 2004; 10:17 a.m.


I've recently bought a Epson R800 and I'm trying to figure out which resolution I should print at. Here are some of the argument sI've seen on other posts:

1) Print at 300 dpi by resizing the image appropriately in Photoshop. 2) Print at 360 or 720 dpi 3) Send an image to the Printer and let it handle the resizing and resolution.

Anyone have any definitive answers on this?

Thanks, Dave


    1   |   2     Next    Last

B G , Jul 30, 2004; 10:21 a.m.

I vote for #3

doug nelson , Jul 30, 2004; 10:25 a.m.

My Epson is an aging 870. 240 ppi going in, and printing at 720 dpi usually gives a decent result. It may be my imagination, but I think the printer responds well to 300 ppi going in, and printing at 720. I don't print at 1440 dpi unless I have 450 ppi going into the printer. There's a good reason for storing your images at 300 ppi. It seems to be a standard for print quality. Should you sell one, the buyer will likely ask for 300 ppi. An 8 x 12 at 300 is enough for most of my purposes. You can just feed your stored image into the printer (after a judicious hit of Unsharp Mask, if you haven't sharpened already). You'll get a little cropping (since paper is 11 1/2 long), but a nice print.

Marshall Goff , Jul 30, 2004; 10:38 a.m.

There is a lot of math on this, and some of it is pretty convincing. That said, I did a few tests on a couple different papers, and found that I personally could see very little, if any, benefit to going over 300, and could see the difference between 240 and 300. For me, that answered the question for what I use for most of my printing on a 1280. [I did a similar test for 1440 vs. 2880 in the printer driver, and it was less conclusive on certain papers.] It is worth getting advice on this stuff from knowledgeable people, but I still recommend doing the test yourself at some point because it can be very educational. Enjoy.

Jeff Spirer , Jul 30, 2004; 10:44 a.m.

It doesn't take too much work to do a test and find out what you like best. It takes about 30 minutes to do all that testing, and you may feel different than other people do about it. Also, it is somewhat paper and subject dependent.

Jean-Baptiste Queru , Jul 30, 2004; 10:46 a.m.

I go for #3. I've been involved in writing printer drivers, so I have an idea of what goes on inside, and I know that there's no reason to not trust the printer driver.

Jim A , Jul 30, 2004; 11:11 a.m.

On my 1280 I print at 1440 and size my images at either 288 or 360 dpi (depending on how big the image is) since they are divisions of 1440. But having said that, in my unscientific tests I could not see a difference between images made at 288, 300 or 360 dpi. Do a test and let us know what you find out.

Steven Clark , Jul 30, 2004; 11:55 a.m.

Epson printer drivers will make use of high-contrast image information ranging all the way up to 720 ppi. Really you should never worry about downsampling or the like, if you have more than 300ppi just hand it off the the printer and it will probably make at least some use out of it.

Michael Lopez , Jul 30, 2004; 12:39 p.m.

I can't answer this question, but would like to bring up a related issue. Perhaps Jean-Baptiste would be able to shed some light.

On an inkjet printer, each color pixel contains multiple dots. With yellow, cyan, and magenta inks, and a single dot size, only 8 colors can be printed within a single dot position (yellow, cyan, and magenta from one color of ink; red, green, and blue from combinations of two inks; black, by combining all three inks; and paper white, from no ink in that dot position). Using the same technology, getting a color depth of 256 colors (8x8x8 levels of YxCxM) requires clumps of 8 dots to form each pixel. Sophisticated inkjet printers use more complex technologies, with variable-size dots and an additional two colors (light cyan and light magenta). Then 256 colors can be mixed with fewer than 8 dots per color pixel, or more than 256 colors can be mixed within an 8-dot pixel.

The fundamental questions, then, are:

1) What is the color depth of a JPEG file?

2) How many printer dots are required to reproduce one colored pixel of that color depth with (a) three ink colors and one drop size; (b) three ink colors and multiple drop sizes; (c) five ink colors and multiple dot sizes?

3) Does the printer resolution setting refer to the number of dots per inch or to the number of color pixels per inch?

One other issue. Some printers have assymetric dpi capacities, e.g. 1200 dpi horizontally by 4800 dpi vertically. If each color pixel requires 8 dots, and those dots are laid out in an array 2 dots wide by 4 dots high, then the printer can produce up to 600x600 full-color pixels per inch. Assymetric dots per inch produce symmetric pixels per inch.

Understanding the relationship between printer "resolution", printer dots per inch, and printer pixels per inch would imply a maximum printer resolution beyond which one would have to sacrifice color depth.

Jack Paradise , Jul 30, 2004; 12:59 p.m.

"1) Print at 300 dpi by resizing the image appropriately in Photoshop."

When you resize you image in Photoshop it will be in pixel per inch (PPI). When you set y our printer resolution setting it will be in dpi.

So, size your image at 240ppi or more and print at the highest resolution (dpi) setting of your printer: 1440 or 2880.

    1   |   2     Next    Last

Back to top

Notify me of Responses