Jackie,
OPI in its true sense means 'Open Pre-press Interface'. Very common some years ago when computers and networks were very slow. You purchased an OPI application which would then 'swallow' high resolution images and 'spit-out' low resolution *copies*. The designer (or similar) would then place/import the low resolution image into their Quark/InDesign layout. This then enabled the file import and subsequent file manipulation on-screen and proofing to be very quick.
When the time then came to print - the OPI system would then 'silently' swap back the high-resolution image - since the file names were always the same. It all worked very transparently.
There were some niggles however - people experienced issues when you tried to colourise an OPI image - this would not reflect in the original high-res file ... and sometimes the high-res image would move slightly. I know OPI is more stable these days ... but that gives you some history.
Distiller actually gives you the option to have the same ..... You could produce a postscript file (which uses the OPI images) and then Distill - providing you turned the 'OPI Comments' ON within Distiller. When the PDF is then sent to a RIP - the OPI system knows to swap-in the high resolution images.
The downsides to this were that since the final OPI swapping could only take place on the RIP just prior to the print job - many people felt un-easy about proofing a PDF to a client if that *might not* be the final/ultimate PDF.
Also - CPUs and network speeds have increased substantially .... therefore you could say that the need for OPI is no longer required - though some people with huge files might disagree.
Regular PDFs created with the 'Preserve OPI' option selected in Distiller contain a particular file/path-name and objects called 'FormsX' and this can be problematic to RIPs.
As previously mentioned, the 'OPI' category was selected by default in the PRESS settings for Distiller 4 and 5 ... therefore confusion has arisen.
I trust this helps,
Jon
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On 5 Apr 2004, at 11:40, J Jackson wrote:
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And as far as OPI goes, Adobe isn't the only culprit. Quark 6 still has OPI
turned on as the default. And most users have no clue what it is so leave it
alone.
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This thread has been very interesting to me. I'm one of those who have no
clue, but I did read, somewhere, OPI can cause problems. We impose pdf's
into Quark to RIP, some just wouldn't go. When I had the designers uncheck
OPI, most worked.
Now my question, what is OPI and why would I need it?
I've wanted to ask for sometime, but lurked instead. I have no formal
training, just had to jump in & learn what I can. This list has been
invalueable!
Jackie
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