Rosettes developing in Cezanne > Agfa Acento II CTP setup

[jyarrow]

We are testing scanning in already scanned jobs and I took a job and scanned it at 3 target resolutions (1200, 600, 300 dpi) and set up a plate and output it to our Agfa Acento II platesetter.

Even though the files look great on the screen, it looks like either the RIP (Xitron Navigator 8.3.1) or the imagesetter is applying another screen and creating a rosette pattern. This pattern is much more apparent in the higher resolution than it is in the lower resolution. It almost looks like the 300 is close to perfect. Almost makes me wonder if 150 dpi won't even be better.

Any idea why this might be happening?

Jim Y.

 

[gordo]

We are testing scanning in already scanned jobs.

Could you explain what you mean by that? Or provide more detail as to what it is that you are scanning and what does already scanned jobs mean. If it's already scanned, whatever that means, why are you rescanning it?

best, gordo

 

[jyarrow]

Correction: Previously run jobs from negs

Correction: Previously run jobs from negs

Correction to my previous post. I am scanning negs of a job that we ran in the past. It has gradiated screens on it, thus I thought it would be a good test. I tried scanning it in grayscale to 300, 600 and 1200 dpi. I think the RIP believes it's a grayscale picture because it seems to be applying a new screen to it.

In the Cezanne software (Color Central) I tried to tell it that it was a Black Separation then it wanted to scan the file as a bitmap at 360 dpi. I went ahead and did that scan, but most of the line screens were lost in the process. I'm a bit lost on how to scan this job in so that I get the content but without it seeming to the RIP like a grayscale image. Thanks so much,

Jim Y.

 

[gordo]

Correction to my previous post. I am scanning negs of a job that we ran in the past. It has gradiated screens on it, thus I thought it would be a good test. I tried scanning it in grayscale to 300, 600 and 1200 dpi. I think the RIP believes it's a grayscale picture because it seems to be applying a new screen to it.

In the Cezanne software (Color Central) I tried to tell it that it was a Black Separation then it wanted to scan the file as a bitmap at 360 dpi. I went ahead and did that scan, but most of the line screens were lost in the process. I'm a bit lost on how to scan this job in so that I get the content but without it seeming to the RIP like a grayscale image. Thanks so much,

Jim Y.

You are double posting which is going to be confusing.

At the end of the day you need to send a bilevel bitmap image to your RIP (in PShop: image--->mode-->bitmap-->50% threshold). If it is in anyway grayscale (e.g."Black Separation") the RIP will halftone screen it. If it is a bilevel bitmap then there is no bit depth. I.e. there is nothing for the RIP to screen. So, maybe bring the grayscale image out of Cezanne and into PShop and convert to bitmap. You could even open the scan in PShop and do an image--->adjustments---threshold. Move the slider and see how the image changes according to the threshold where gray pixels become either black or white.

best, gordo

 

[VladCanada]

When I was reading this thread, some words appeared from my memory: CopyDot scanning Software, XY-15, T5000 AGFA Scaners... and disappered back into the fumes of the Past

 

[jyarrow]

Problem resolved

Problem resolved

You are double posting which is going to be confusing.

At the end of the day you need to send a bilevel bitmap image to your RIP (in PShop: image--->mode-->bitmap-->50% threshold). If it is in anyway grayscale (e.g."Black Separation") the RIP will halftone screen it. If it is a bilevel bitmap then there is no bit depth. I.e. there is nothing for the RIP to screen. So, maybe bring the grayscale image out of Cezanne and into PShop and convert to bitmap. You could even open the scan in PShop and do an image--->adjustments---threshold. Move the slider and see how the image changes according to the threshold where gray pixels become either black or white.

best, gordo

Thanks so much for your response. I finally got guidance on the special mode I had to use to get 1 bit files and now everything (for the most part) is ducky. Now my RIP likes the files and doesn't try to screen them further.

Jim Y.