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Prathap · #1 (**permalink**) 08-13-2007, 10:29 AM

Hello ,
I am looking for some details on what exactly does 1 bit workflow mean?
I looked on the google too...but not much helpful.
Any articles or any good information would be appreciated.

Cheers !!
Prathap

Joe · #2 (**permalink**) 08-13-2007, 10:42 AM

To me it would be a workflow that in the end outputs a one-bit tiff of each separation to be imaged, either by a CTF or CTP device.

DCurry · #3 (**permalink**) 08-13-2007, 03:36 PM

I think it means, in addition to what Joe said, that the screening is already applied at the last stage before imaging. That means that if you are imaging 1-bit files, the screen angles and frequency is built into the 1-bit file, as opposed to the screening being applied on the fly as it is imaged.

I output from a Brisque to a Lotem platesetter, and it is not a 1-bit system. I can image the same ripped file at various linescreens and angles without having to change the file at all.

Prathap · #4 (**permalink**) 08-14-2007, 01:44 AM

Hi Joe / DCurry,
Thanks a lot for the information.
But I thought the Screening and the frequency information is written to the bitmap data while rasterizing itself. Am I wrong???
Anyway, who discovered these stuff? I am sure his wife was not around...

Or mite have died as a bachelor....

Cheers !!

Earendil · #5 (**permalink**) 08-14-2007, 06:58 AM

I use a Xenith Xitron workflow and it creates 1 bit tiff files of each page of a PDF before the imposition stage. It also creates a low rez set of eps files for placement in Preps which are like FPO images. The RIP then replaces the placement files with the 1 bit tiffs when I print the job back to the RIP from Preps and send to the platesetter.

You do have to rip the original files specific to line screen and in my case, the particular plate and press the job will run on meaning you can't change your mind at the imposition stage.

The nice part is, the files are fast and easy to deal with in Preps since they are small placement files. Also, if I have a late correction, say after the proof, I just rip the new page(s) and use a placement editor in the workflow to replace the page instead of having to go back to Preps.

I can use a viewer in my rip manager client to view each separation of each page with the exact screening, dot for dot as it will appear on the plate.

Joe · #6 (**permalink**) 08-14-2007, 08:06 AM

Quote:

Originally Posted by Prathap

Hi Joe / DCurry,
Thanks a lot for the information.
But I thought the Screening and the frequency information is written to the bitmap data while rasterizing itself. Am I wrong???
Anyway, who discovered these stuff? I am sure his wife was not around...

Or mite have died as a bachelor....

Cheers !!

In my case that is correct. It is screened while being rasterized into a one-bit tiff. I believe DCurry was saying he does not have a one-bit tiff system and his is screened as being imaged from, I'd suppose, a PS file.

Earendil · #7 (**permalink**) 08-14-2007, 08:14 AM

Everything that gets sent to an imaging device, i.e. platesetter, imagesetter, laser printer, ink jet, etc... gets turned into an image file at some point before going to the device. They are all just image plotters of one form or another. In the case of our large laser devices, 1 bit tiff is the way it's done, it's either a 1 or a 0, the bit is on or off since the plates are monochromatic.

DCurry · #8 (**permalink**) 08-14-2007, 09:22 AM

Quote:

Originally Posted by Joe

I believe DCurry was saying he does not have a one-bit tiff system and his is screened as being imaged from, I'd suppose, a PS file.

Not quite - the PostScript or PDF is ripped into a ripped CT/LW (Contone/linework)file, which still is not screened. I can then image that ripped file at a number of linescreens without further interpretation.

Earendil · #9 (**permalink**) 08-14-2007, 09:28 AM

Quote:

Originally Posted by DCurry

Not quite - the PostScript or PDF is ripped into a ripped CT/LW (Contone/linework)file, which still is not screened. I can then image that ripped file at a number of linescreens without further interpretation.

In this case it gets rendered to a tiff at the end of the game, just before imaging, but it does become an image, and probably a tiff, before the plotter gets a hold of it. I used to work on a Dolev system that worked just like this, there are pros and cons to both.

In the end, it's all raster!

Prathap · #10 (**permalink**) 08-14-2007, 10:13 AM

Dear Friends,
Here is what I know about 1 Bit Workflow.
Correct me if I am wrong again.

Whenever a file is RIPed it converts the CT/LW into bitmap data.
Now during this process of conversion, the file is subjected to screening where the screen angles & the frequency are applied to the data.
This data is now used for either for Imposition as per my friend "Earendil" or can be Output directly to a device.

Now if we cut the cable that flows across to the Imaging device we definitely could find a 1 Bit data flowing across it.

Earlier this data could not be captured after RIPping & it would be directly sent to the Imaging devices. (Which still some people do)
Hence ending up in debating results or having its pros and cons.
This consumed a lot of time for RIPping huge files / layouts.

As per Earndil, now the data (1 Bit TIFF) that comes out of the RIP, is captured and Low Res data files can be generated and could be used for Imposition.
This surely helped in last minute changes / different styles of imposition etc.
I had worked on Xiflow and Preps almost 2 years ago, and found its own Pros & Cons. However the Navigator RIP is like a Ferrari.

Finally while output to the imaging device, the Low Res data was now swapped to the High Res.
This data when sent to the laser head as 1 or 0,
Depending upon "Imaging" & the "Non Imaging Areas". the head used to turn either "ON" or OFF " . Thus attaining WYSIWYG

Any comments would be appreciated
Thanks for the Info guys.

Cheers !!