QTR-Quadtone RIP

Thanks Roy,

That is something I guess will just have to be worked around - no value higher than 254 in an image.

As far as the gradient, there are vertical lines visible that seem to be separating the tones as opposed to a smooth transition.

Thanks

Alan

On Mar 10, 2014, at 2:13 PM, Roy Harrington wrote:

Hi Alan,

That's a known behavior. It was mainly introduced for people putting gloss-optimizer onto photo paper prints.

The way the whole OS printing system works there is nothing distinguishing pure white of an image from

pure white border around any image. So the idea was to eliminate all ink for pure white -- you could put GO

for everything from 0 to 254 and then cut-off the GO at 255. Basically you get control of where you want GO

by giving up the one gray value. So the QTR profile maker clears the pure white value of the ink.

Ordinarily this has no effect in other situations but you've found one here. You can take advantage of it

to control how much black border you want around your negative -- not having to alway cover the whole sheet

with black.

I don't know what you mean by the "choppy look on the right hand side of the gradient". It may be

just the scan but I can't see anything particular or strange.

Roy

On Mon, Mar 10, 2014 at 8:07 AM, Alan Vlach <alanvlach@...> wrote:

Roy,

...

As you can see the 0% or 255 value printed white instead of black. The gradient at the top of the wedge showed the darks printing till the very end where it printed white again.

I opened the step wedge in photoshop and applied a levels layer which changed the output value from 255 to 254:

...

I printed this image and got the expected result.

I'm also curious about the choppy look on the right hand side of the gradient.

Thanks for all your help,

Alan

--
Roy Harrington
roy@...
www.harrington.com