OK, Andy and others, I've thought about this for a little while.
I've been involved with digital photography for only about five years.
During that time I've heard about RIPs being used in the printing process.
I print on my own, but have never come across a real -- as opposed to
advertising -- explanation of what goes on and what the advantages are.
I know that at least one Forum member uses a RIP; anyone care to help me
out? I have an Epson 3800 that does very good black and white; should I
care about a RIP???
Architects (used to?) use rips that are incredibly precise when it comes to
measurements - It's argued for most pictorial use, images that are stretched
a bit are not an issue, so a rip for them means absolute precision, same too
if you were doing circuits.. sending an image to a rip designed for such
things means farming the image across without needing to fuss about
resizing, it will be informed by the program pecisely what size the image
should be and thus circuit pin placement will not be compromised.
Of course most modern printers have such good RIPS, needing anything
aftermarket is largely a thing of the past - think of the last time you saw
a wlldly distorted image - to all intents and purposes, probably never.
However think about upsizing images - you grab a small image and either use
the limited Photoshop algorithms to do 10% increments until you get
something large, but odds are you've basically got a large fuzzy image. Or
you use a specific upsizing algorithms and get something much better.. or
you pam it of to Genuine Fractals (just another suite of upsizing
algorithms) and maybe get something better again.
How many people just send it straight to print these days without all the
upsizing, and get a better image straight away than if they upsized in an
image program? You may be surprised to see just what a printers inbuilt rip
can do without any efforts from you or I - their rips are pretty good these
days and they'll often do a better job than what you can do
Ramp that up a few notches and try to make a wall sized print and you'll
probably need a hardware rip - a machine on the network armed with it's own
software rips loaded that passes the image through a whole series of
algorithms, crunches the numbers, and then sends the image to print, often
directly using the printers hardware via the format in which the image is
sent - much the same as using Vuescan allows the user access to the hardware
directly in a way that circumvents the scanner software (in the case of
vuescan, allowing single-pass scanners to do multipass and so forth).
The results from such a hardware rip can be startlingly good. To a casual
viewer thay would just look at the postcard original, look at the wall sized
print and shrug.. 'yeah, looks the same'.. but as you and I know, a small
image can look a lot sharper than it actually is. Our minds extrapolate the
image up - but if you looked close at the postcard, all you'd really see if
a fuzzy mess of misplaced dots - to take that to a wall sized print that
looks anything close to decent is a huge task, and exactly the sort of thing
handled by a good rip.
then again there are other types of rips, program hybrids I've mentioned
here before like Rasterbator http://rasterbator.net/ or Andreamosaic
http://www.andreaplanet.com/andreamosaic/ * the former allows you to creat
mosaic images, printing elements of your iamge across multiple sheets.. The
latter program is given a source image, a folder full of images from which
it may dip to construct elements of your main source image, and it will
compile your source image from dozens or hundreds of other images and send
them to print - you've probably seen the Star Wars Yoda poster constructed
from hundreds of stills from the movie.. These can't really be called pure
rips, but they kinda are - and they illustrate using extreme examples of
just what can be automated in producing a final print.
Should you care about a rip? these days I'd say for 99% of people using
your printer, probably not so much. Knowing a bit about them though is
good as the more you know, the better armed you are for any task that comes
your way and the more able you are to see faults in print output and be
aware of the options available to you. Most people need know little about
upsizing or downsizing algorithms (though I wish they would learn more) but
knowing a bit means when you downsize an image and see a set of steps turn
into a mess of moire, bands and patterns instead of clean delineated steps..
you at least can *see* it, and then can take steps to find a better
algorithm to make sure you don't see it in your print image..
Maybe it could be fun to feed 1000 images of a youth across the years into a
rip to produce a mosaic showing granny as she isa now. Maybe it'll just
earn you a slap -
here's a bit more.
https://en.wikipedia.org/wiki/Raster_image_processor
Andreamosaic examples:
http://www.andreaplanet.com/andreamosaic/samples/
rasterbator image:
http://community.digitalmediaacademy.org/wp-content/uploads/2011/09/rasterbation-moonwalk.jpg
