Black and White Printing on Offset - never cracked this subject

[ashwini singh]

Hi Guys,
what would be the best way to print a high quality black and white coffee table book. I know softwares and editing can go upto any extent, but i am getting CMYK edited images from the agency and not much can be done in pre press.
Printing black and white in CMYK always has the magenta tone which can come. is that the best way possible to have depth ?

Single color black is too flat

Can i print it in special colors i.e. 2 color or 3 color black or pantone greys to cover the Highlight shadow and midtones ?

any input would help.. have always had this in mind and have never been able to crack this subject

 

[gordo]

Hi Guys,
what would be the best way to print a high quality black and white coffee table book. I know softwares and editing can go upto any extent, but i am getting CMYK edited images from the agency and not much can be done in pre press.
Printing black and white in CMYK always has the magenta tone which can come. is that the best way possible to have depth ?

Single color black is too flat

Can i print it in special colors i.e. 2 color or 3 color black or pantone greys to cover the Highlight shadow and midtones ?

any input would help.. have always had this in mind and have never been able to crack this subject

Using CMYK to print a greyscale image is suitable if the document the greyscale image is printed in has mostly color images. The use of 4 colors will help the greyscale image to be printed with a richer appearance than just using one ink can achieve. You would use heavy GCR for the separation to help with color stability and neutrality for the greyscale image. If you see a magenta cast in your work it may simply be because there's too much CMY in the separation and the lighting under which you are viewing the image is biasing the Magenta/Red.

If it's a coffee table book with many greyscale images then yes, duo or tritones are the best way to reproduce greyscale images. You can do two hits of Black or use Black plus one or more Pantone greys. A good paper supplier should be able to show you printed samples of this kind of work as a guide to achieving the effect you're after. Or, you can do a press test.

 

[Stephen Marsh]

…I know softwares and editing can go upto any extent, but i am getting CMYK edited images from the agency and not much can be done in pre press.
Printing black and white in CMYK always has the magenta tone which can come. is that the best way possible to have depth ?

I respectfully disagree, you can do something constructive, even with supplied CMYK content – even with just PDF files and Acrobat Pro. If you have other tools such as a colour server, PitStop or PDF Workflow software then even more can be done.

A CMYK gray colour cast can be warm or cool, for people images a magenta or warm cast is generally more acceptable than cool. By using a really heavy or maximum black GCR style separation method most of the weight can be placed into the black channel, with the CMY basically adding density to the shadows and only making minor contributions to the remaining tonal range, minimising the chance for colour casts while still adding density to the shadows.

Can i print it in special colors i.e. 2 color or 3 color black or pantone greys to cover the Highlight shadow and midtones ?

Yes, for example Photoshop has provided duotone/tritone/quadtone presets for years and other tools such as PitStop can likely do this as well for PDF files.

The problem is often in proofing the results in a predictable manner.


Stephen Marsh

 

[ashwini singh]

Thank You,
We are doing a machine proofing to see both results i.e. CMYK and Tritone.
The confusion which i know face is the tones of the Greys or Blacks used in the tritone , for instance do i use 1 black and two warm greys or do i use a black a dark grey and a lightish grey.

Fingers crossed , results should be out in the next few hours.

 

[dabob]

One of the biggest issues that I have seen in printing bnw halftones is the density of the blacks . . in photography (old school) the dmax would be about 4.0 and with a single pass of black ink (even a dense black) when compared to the photographic print looks washed out and has a significantly lower dmax than photo paper. One way around this is to print a duo, tri, or even a quadtone with black in all the channels . . . it builds the density in the shadows and adds details in the mid and highlight zones.


Just my 2 cents on this issue but using this method will eliminate any color shifts on the press caused by variation in the press runs.

 

[gordo]

Thank You,
We are doing a machine proofing to see both results i.e. CMYK and Tritone.
The confusion which i know face is the tones of the Greys or Blacks used in the tritone , for instance do i use 1 black and two warm greys or do i use a black a dark grey and a lightish grey.

If you use CMYK for a greyscale the you will likely see color shifts under different lighting conditions because the image includes chromatic inks which will shift hue under different lighting.
If you only use non-chromatic inks (black & greys) then this won't happen.

Typically one uses Black and dark grey or two blacks. Or black and two greys (dark and medium/light)