Stochastic Screening

[HiTech_Monkeyboy]

Greetings to everyone!

I was wondering if anyone out there is using stochastic screening with a Brisque 5 system and what issues (any and all) came up while going stochastic. We're looking at making the leap but want to know what rocks are at the bottom of the cliff so to speak.

Thanks in advance,
Monkey

[steveagfa]

Dear MonkeyBoy:

It's less of an issue with the Brisque -
but rather the imager and plate combo.
Most of the heavy lifting with stochastic
is getting the plate/imager system optimized.

What we are finding is that plates like
Azura or Amigo have a tremendously
wide exposure window, and no to little
process variables, so the use of stochastic -
officially certified to 25 microns over the
plates' full rated runlength by Kodak/Creo -
tends to be easier when you remove these
process variables.

So, even with a system that is not "optimized"
or carefully honed to enable stochastic, users
are finding great results, due to the removal
of these process and imaging variables with
Azura and Amigo.

Pardon the plug - but we are finding a great pairing
with stochastic and Agfa's Thermofuse technologies.

Look not at the Brisque, but rather the process.

[HiTech_Monkeyboy]

Ah, point taken, should've included the trendsetter and LT-2 plates.

[mc_hristel]

I can tell you the pressmen hate it. What you see is what you get on press. Ink level adjustments on press never changed color balance much if at all. The other thing we saw a lot of was exagerated banding in gradients. We were fighting with plate chemistry a lot too which probably didn't help.

If you do a lot of printing with solids or blocks of color I wouldn't bother. You will have better solids with traditional line screens. If you print a lot of halftones or things with pictures though, stochastic can give you some nice looking results.

We were running Brisque 4 and Trendsetter with Kodak thermal gold plates but I don't think there was any change in how the stochastic is handled in Brisque 5.

[jimking]

That's what I've heard is that scenic photos etc look very nice but color builds and solids are a problem. It makes sinse because I think that pantone color builds are built on dot or rosette rather than a random dither thingy. Lets say you have a 4/c build of pms 300, could stochastic screening match it?

[Rickyp_uk]

From what i've seen it is brilliant for pix but not with layout content i.e solids, tints and gradients of colour. Its ideal application is through apps like Artpro where u can specify what elements have what type of screening, and as mentioned above machine minders don't tend to like it.

[Rickyp_uk]

Originally Posted by jimking

That's what I've heard is that scenic photos etc look very nice but color builds and solids are a problem. It makes sinse because I think that pantone color builds are built on dot or rosette rather than a random dither thingy. Lets say you have a 4/c build of pms 300, could stochastic screening match it?

It can be matched but the problem seems to be in the tolerence for adjustment which comes with stochastic. Small adjustments on press seem to have greater effect on paper.

We tended to use it for poster work

[HiTech_Monkeyboy]

How much trouble is it to come up with color curves?

[Rickyp_uk]

Not too difficult just take your time. Its preferable to get the minders in on the action so they don't feel like your dumping it on them. Treat it as if your footprinting the press, get yourself a good calibration sheet sorted (which doesn't just contain wedges), contract proof it then let the games begin!

Originally Posted by Rickyp_uk

..Its ideal application is through apps like Artpro where u can specify what elements have what type of screening, and as mentioned above machine minders don't tend to like it.

Heidelberg's new Prinect workflow does this too.
Pretty sweet when you can run some elements as stochastic and the other stuff as standard dot on the same page..