Inkjet printer best results. RIP software ?

Dear members:


This is my first post to the group and I don't have much experience with
printing technologies so I apologize if my questions seem rather basic.

Although I have been using inkjet photo printers for a while, I have began
to question whether I am really getting the best results I can for my
printed photos. They look very good and in fact rival anything I ever got
from film and traditional chemical developing techniques. However, I feel
that with the current digital technology and the quality of the files I work
with the prints could (and should) look better.

I work with two Epson printers - a Stylus Photo R1800 (resolution of 5760 x
1440) and a Stylus Photo 900 (resolution of 5760 x 720). The printer driver
provides options that vary according to the paper type selected but one has
no control over the resolution used for printing. With this in mind, here
are my questions:

1. I work with files generated by a Canon EOS 1Ds Mark II digital SLR that
produces images with a resolution of 4992 x 3328. When printing a 8" x 10"
photo these files should allow a resolution of 499.2 dpi along the longest
dimension and 416 dpi along the shortest dimension. In case the same file is
used to produce a 4" x 6" photo, the resolution would be 832 dpi along the
longest dimension and the same 832 dpi long the shortest dimension.
- How do I know if the printer is using every pixel provided by my file and
placing each pixel on the printed photo instead of just defaulting to the
popular 300 dpi ?
- How can I control the final resolution and force the printer to use all
the available pixels on the image file ?
- In case I choose a resolution that exceeds that of the image file, will
the printer interpolate to create dots on the printed photo that do not
exist in the original image file ?

2. How exactly does RIP software work ? Would I benefit from using a RIP
application and will it give me control over printing resolution and other
features that I can't control with the standard printer driver available for
these printers ?

3. What do you think of PrintFab for the Macintosh ? Is this a good RIP ?
Does it provide increased control over the final print and what kind of
features does it have ? Is there another inexpensive (considering this is
for personal use) RIP you would suggest that would provide me more control
over the printing process and help me improve the quality of my prints ?

In case this is important information, I work with a PowerMac G5 dual
processor 2.0 GHz and it runs OS X 10.4.10 (latest version of Tiger).

Any help will be greatly appreciated.

Thank for your help,

Joseph Chamberlain

On Tue, 6 Nov 2007 05:17:30 -0500, Joseph Chamberlain, D.D.S. wrote
(in article ):

> Dear members:
>
>
> This is my first post to the group and I don't have much experience with
> printing technologies so I apologize if my questions seem rather basic.
>
> Although I have been using inkjet photo printers for a while, I have began
> to question whether I am really getting the best results I can for my
> printed photos. They look very good and in fact rival anything I ever got
> from film and traditional chemical developing techniques. However, I feel
> that with the current digital technology and the quality of the files I work
> with the prints could (and should) look better.
>
> I work with two Epson printers - a Stylus Photo R1800 (resolution of 5760 x
> 1440) and a Stylus Photo 900 (resolution of 5760 x 720). The printer driver
> provides options that vary according to the paper type selected but one has
> no control over the resolution used for printing.

Errm.. yes you do. 'Draft', 'normal', 'best', and (on some printers) 'photo'
or 'best dpi' all change the output res.

> With this in mind, here
> are my questions:
>
> 1. I work with files generated by a Canon EOS 1Ds Mark II digital SLR that
> produces images with a resolution of 4992 x 3328. When printing a 8" x 10"
> photo these files should allow a resolution of 499.2 dpi along the longest
> dimension and 416 dpi along the shortest dimension. In case the same file is
> used to produce a 4" x 6" photo, the resolution would be 832 dpi along the
> longest dimension and the same 832 dpi long the shortest dimension.
> - How do I know if the printer is using every pixel provided by my file and
> placing each pixel on the printed photo instead of just defaulting to the
> popular 300 dpi ?

Many modern inkjets default to 600x600 dpi for 'normal' output. If you change
the output to 'best', they go as high as 1200x1200 dpi, sometimes higher,
depending on the printer. Epsons typically max out at about 1440x5760. Your
two Epsons will match the 832x832 res of the pic produced by the Canon. The
900 will not produce as good output as the R1800, but then the R1800 is a
better printer. 'Photo' output is designed for photo paper and has
not-very-good results when used on other kinds of paper.

> - How can I control the final resolution and force the printer to use all
> the available pixels on the image file ?

The printer software is often delivering (interpolated) output at a high res
than the image. If you want to use a specific ppi level, you can get the
(free!) PostScript 3 clone drivers available for many (but not all) inkjets
at places like <http://www.linux-foundation.org/en/OpenPrinting/MacOSX/hpijs>
and <http://gimp-print.sourceforge.net/MacOSX.php3>. If you then go to
<http://127.0.0.1:631/printers> (note: 127.0.0.1 is the local loopback
address for your own computer, and port 631 is the Internet Printer Protocol
port) you can manipulate the output to your heart's content. You should know
going in that unless you're going to tweak things individually for each new
print job, the default print settings are liable to deliver better output
than your tweaks.

> - In case I choose a resolution that exceeds that of the image file, will
> the printer interpolate to create dots on the printed photo that do not
> exist in the original image file ?

Yes.

>
> 2. How exactly does RIP software work ?

The software rasterizes your file, scanning it line by line and producing
information for the page layout software so that the software can calculate
the exact position (and, in the case of colour systems, the exact colour in
the CMYK colourspace) of every dot. The printer driver then attempts to place
those dots. Some printers are better than others at matching colours and
exact positioning; a $50 inkjet printing to plain copier paper is going to
produce output noticeably inferior to that of a $500 photo printer printing
to photo paper, which in turn is going to produce output noticeably inferior
to that of a $50,000 imagesetter printing to film. Even if all three are
using the exact same page setup language, PostScript 3. Hell, even if all
three are using the exact same RIP software.

> Would I benefit from using a RIP
> application and will it give me control over printing resolution and other
> features that I can't control with the standard printer driver available for
> these printers ?

Sure, if you buy a better printer. A free RIP might give better results than
the driver which ships with the printer, especially if you use HP inkjets, as
HP drivers stink. (Note: the HPIJS drivers are mostly written by HP
employees, and are in many cases superior to the drivers which ship with HP
printers. It is left as an exercise for the student to determine why HP ships
inferior drivers with its printers when it _pays its people to produce
superior drivers, which it then gives away for free_.) There are serious,
high-end, PostScript RIPs available which can produce very high quality
output even with relatively low-end inkjets... but those drivers cost many
hundreds of dollars. How badly do you need that output? Professional users
can recover the cost of the high-end drivers with a single project; home
users, now...

>
> 3. What do you think of PrintFab for the Macintosh ?

It's expensive.

> Is this a good RIP ?

It works.

> Does it provide increased control over the final print and what kind of
> features does it have ? Is there another inexpensive (considering this is
> for personal use) RIP you would suggest that would provide me more control
> over the printing process and help me improve the quality of my prints ?

See above, the HPIJS and GutenPrint rips.

>
> In case this is important information, I work with a PowerMac G5 dual
> processor 2.0 GHz and it runs OS X 10.4.10 (latest version of Tiger).
>
> Any help will be greatly appreciated.
>
> Thank for your help,
>
> Joseph Chamberlain
>



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