Why, you can be lazy and I can't? I posted a link that explained ALL the
questions you kept ansking yet YOU were too lazy to click on the link I
spent time searching FOR YOU!!!! Sorry I'm done...

On Wed, 27 Apr 2005 21:22:41 GMT
In message <BoTbe.8679$J12.2834@newssvr14.news.prodigy.com>
Posted from SBC http://yahoo.sbc.com

DPI / PPI same thing depending on the context.  No need to mince
acronyms... pixels per inch, drops of ink per inch, and sometime drops
of ink per inch are discussed as "many drops of ink that make up the
equivalence of an original pixel".

Heck, Adobe spells "color" correctly but we don't argue about "colour"
very often...  <vbg>

Jeff

People use these two interchangeably even if they aren't precisely the same
thing, yes PPI is probably the correct term but I bet the manual for the
printer would call it DPI..

It means, simply that the printer can fire tiny droplets of ink on the
paper at 4800/inch.  Since it may take up to 6 or even 8 droplets of ink
on the paper, and these often merge together, a 'dot' can be somewhat
larger, or smaller, depending on how may droplets are sprayed to get the
desired color.  Add to that the ability of some printers to spray
droplets of different sizes, and the matter becomes indefinable by any
consistent system.
More is better, but the equation is NOT linear.

I'm happy with mine once I bought a custom printer profile for it..

...

...
Brian:

That specific answer depends to varying degrees on your printer, your
camera, and your eyes.  }:)

Manny people use 300 ppi as the goal for "great" photos.
Some demand 600 ppi, others are happy with 200 ppi, but for the sake
of argument let's go with 300 ppi.  You can do the math any other cases.

To print a 6 x 4 photo at 300 ppi would require (obviously)  6 x 300 x 4 x 300
= 2160000 pixels or 2.1 MP.  Remember that the shape of the picture from
the camera is different from the shape of a 6 x 4 photo, so some of the original
will have to be cropped if you want an edge to edge print.  Ignoring that,  you
want 2.1MP.  One camera provides 1.3 MP, less than you want.  One camera
provides 6 MP, more than you need.

Next, of what pixel resolution is the printer capable?  Not the "dots per inch"
spec of the printer; it takes a lot of dots to actually represent pixels of the
correct colors.  A cheap 4 ink inkjet might be capable of 150 ppi.  A good
6 color inkjet might be capable of 300 ppi, or more.  A 300 dpi dye sub
printer can produce 300 ppi.  So, depending on your printer, you might not
be able to actually produce any more pixels than the 1.3 MP camera produced.

Finally, how good is your vision and how closely are you looking at your print?
Under a magnifying glass, you will probably see the differences between any
printers up to 600 ppi.  For a 6 x 4:  At arms length, you probably can't
tell the difference between a 300 ppi picture and a 600 ppi picture.  On the
wall across a small room, you won't see the difference between  a 150 ppi
print and a 600 ppi print.

Now tell me whether you will see any difference.  }:)