Ink Saving solution?

[stargate]

Anyone is using any ink saving solution like alvan cmyk optimizer, cgs ink saver, gmg ink optimizer or rampage inkdrop?

- What is your experience with your solution?

- Does it really work? (do you save ink?)

- how does it integrate with your ripping workflow?

- does it change color visually??

[ArtproPro]

We are using Concentric screening from EskoArtwork. It is supposed to save you ink as well. I haven't tried any of the solutions that you mentioned but i thought i would make the suggestion.

[Lee Hutchinson]

We use Alwan CMYK Optimiser and I can't speak highly enough of it. It does exactly what it says on the tin and the flexibility it offers is excellent.

The latest release V3 adds some really nice features and is well worth downloading a demo of from their site.

Does it really work - in a word Yes. It is very clever and you can cut it any way you want. Change your TAC limit, modify your black generation, change the rendering intent, the list goes on and on. Saving the ink is obviously one thing and there claims of 10% - 30% seem easily acheivable dependent on your work type. It's not all just about the saving for us though, it is the printability, consitency and speed at which we can make transformations from colourspaces from the original PDF's if we switch output device without having to go back to pre-press to re-send.

It fits seemlessly into our worklfow we use Apogee X to create our PDF's that spit them out into the Optimiser hot folders, colour transformation happens and the PDF's are then picked back up by Apogee X. It's all hot folder driven so is very easy to setup.

Does it change the colour visually? The answer really is no it doesn't unless you set it up to the extremes in which case you could get some mismatch but this is really down to the installation and your tolerances. Our experience was if anything the images were better, cleaner, crisper than previously.

Hope this helps.

[jlind]

Why does Concentric Screening claim to save ink? Is this the same as "save ink by printing stochastic?" This has been demonstrated and documented. Just curious about the concentric screening rationale.
John Lind
Cranberry Township, PA
724-776-4718

[GinSu]

Because the dot is really concentric rings, the dot uses less ink thickness since it can gain in both directions from the ring. A normal dot requires more ink since it can only gain from the edge of the dot out.







Another thing to consider is that the originally mentioned methods of ink saving modify the original separations to achieve the ink savings and can effect the color adversely. Concentric dots does not recalculate the separations, the saving comes from the dot shape.

Edited by: GinSu on Mar 4, 2008 11:25 AM

[Hopkins Printing]

Hi Lee,

Which exact flavor of CMYK Optimizer do you use? CMYK Optimizer Prepress? CMYK Optimizer Press? CMYK Optimizer ECO?

Thanks,
Jon :-)

[jest]

We are also using Awan CMYK Optimizer.
It is a great product, thoug it is not the fastest app. to process the files.

With no visual or technical problems it brings the TAC down from eg 355 to 300. The print is perfect and it doesn't stick.

Even when pdf's are delivered in correct colorspace we still convert to a heavier GCR.

So there are many benefits, we save ink, we get a better balance in grey, less deviations in the print run, paper dries better (Heatset)

We have built our own workflow, where we use ApogeeX as rip engine. Alwan connects nicely to APX which makes integration very easy.

In Alwan you can type the price of ink, average coverage and Alwan will calculate how much ink - money you have saved.

I have looked at similar products but Alwan fit our needs 100%.

[patrickvd]

Hi Jesper,

As Sales Director at Alwan, I principle don't want to interfere in these discussions, but as you mention about the speed of Alwan I wan to confirm you that the current Beta version we are testing in our lab's will give you a significant speed increase. Our engineers achieved this amazing result by optimizing the integration with the Adobe PDF library and further optimizing our internal analytics.

Just my 2 cent as I leave comments on the product and results up to our customers......

Regards,

Patrick

[jlind]

GinSu:
The tone value increase comes from the amount of dot perimeter, not the ink thickness. Therefore, your concentric circles will have twice the perimeter, or more, than a 175 lpi dot. Stochastic dots have lots of perimeter. 300lpi dots have much more perimeter than 175 lpi dots. Thus, you can save ink by running 300 lpi screens, just like concentric screening. The ink savings comes from the cut back curves allowing for the final perimeter, or desired tone value increase.
That's my story, and I'm sticking to it.
John Lind
Cranberry Township, PA
724-776-4718

[Erik Nikkanen]

"The ink savings comes from the cut back curves allowing for the final perimeter, or desired tone value increase. "

Well I guess in a way it does. If there is more dot gain with a particular screen type, then the physical dot size would not have to be so big and therefore less ink.

But I think there is a more fundamental reason for ink savings with FM screening and maybe the concentric screening. It has to do with how much ink the image on the plate will take from the form rollers. I briefly commented on this in my 1997 TAGA paper.

The idea has to do with ink film splitting between the plate surface and the form roller surface.

Let's think of a large solid. Normally one assumes the splitting to be 50%-50%. The ink splits and half of the ink film goes to the plate and half stays on the form roller surface. Pretty simple concept.

Now let's think of dots on the plate. Dots are not continuous and their affect on how much ink actually goes to the plate is now more complicated because there is an opportunity for ink to flow laterally. It might even be possible that mid tone AM dots of lower lpi values, could have more ink on the plate dot than the 50% spit situation due to the lateral flow. Fluid mechanics is complicated.

One the other hand, if we talk about very very small dots, one would not expect that a very small dot would be able to pull off a 50% ink film from the form roller. The smaller the dot, the less ink it would be able to pull off the form roller relative to its dot area.

As a side note, this phenomena of less ink consumption affects ink estimation and ink key presetting.

It is clear that if you know that a particular screen uses less ink, then one can estimate ink consumption.

With ink key presetting, there is some confusion in the industry. Some ink key presetting products claim to compensate for dot gain. This unfortunately is an erroneous claim since dot gain is not directly related to ink consumption. Bad science but good marketing.

Some ink key presetting systems also claim to have self learning capabilities. This is also erroneous since each new print design can result in a new set of variables that affect ink consumption. Screen size is just one of many factors. Bad science but good marketing.

Mathematically, a self learning system is not possible becasue each set up could be like having a new set of simultaneous equations to solve. It can be solved if one knows the equations but it can not be solved by a self learning system because the set of equations would change on the very next set up.