How to sharpen imges for a book (printed on a HEIDELBERG offset press)

[manfred1]

Hi,

since many years I print using my EPSON 3800/3880. Usually I do some capture sharpening in Lightroom, maybe some creative sharpening, and finally I resize the image and do output sharpening using Lightroom export. This all works fine.

Now I would like to prepare images for a book. This book will be printed on a HEIDELBERG offset press using coated paper sheets.

The press input will be a PDF file exported with InDesign, using a CMYK color profile (actually ISO COATED V2) as well as a resolution of 300 ppi.

Now I am a little unsure about the right workflow for the book preparation. I am aiming at maximum sharpness for the my RGB images. Is the following workflow adequate?

(1) Do usual stuff in Lightroom / Photoshop
(2) Export the image in Lightroom
    -  using the exact width & height in centimeters as required by the InDesign Layout
    -  with resolution 300 ppi
    -  and this output sharpening: "Sharpen for: Glossy Paper", "Amount: Standard"
(3) Open this image in Photoshop , convert to color profile ISO Coated V2
(4) Place the image in InDesign at the appropriate location
(5) Export the book as PDF in InDesign (no color profile change since all images are already in CMYK)

Does this make sense?

Is there a special sharpening procedure for CMYK images?

Thanks.

Manfred

[digitaldog]

Lightroom's output sharpening is limited to screen or ink jet (not what you need, halftone).
IF you want output sharpening for that target and you wish to do so in Photoshop, there's always PhotoKit Sharpener II which does have halftone output sharpening.

[picman]

I cannot attest to how good it is, but nik sharpener pro also has a halftone setting.

[Rhossydd]

There's also another workflow that avoids having to commit to final printed image sizes from Lightroom and gets dedicated correct sharpening from Photokit Sharpener.

Create all your final images in LR, then export them at full resolution into a folder to import into ID.
Use these images in ID, resizing on the page to suit your layout.
In InDesign run the 'resize to 100%' script from https://sites.google.com/a/lapay.biz/www/scr1-showimageproperties2 this creates a folder of exact sized images via Photoshop.
Then run an action that applies the requisite Photokit sharpener settings to all images in the folder of resized images.

End result a document with exactly sized images with absolutely the best sharpening setting for your chosen process.
Works extremely well with Blurb books and should work well for other presses like the Heidelberg, without the need for tedious pixel by pixel resizing.

[stingray]

Thank you Rhossydd for your response re workflow.

I have a big gripe with Adobe that they do not allow us to place images and text as we wish using the Lr book module, while at the same time not providing us with an efficient workflow to pipe images directly to InDesign, without the need to create intermediate files, etc.  In my personal view Adobe do not understand the meaning of the words "efficient wrkflow". How sad.   I have written my own Javascript to transfer images into InDesign templates, where I preserve my sharpening, ppi and image dimensions, while automatically applying professional level Captions, etc.  This works for printing high quality images, but not efficient for book layouts.

I will explore your suggested workflow for my next book project.

Thanks again.

[JeanMichel]

Hi,

since many years I print using my EPSON 3800/3880. Usually I do some capture sharpening in Lightroom, maybe some creative sharpening, and finally I resize the image and do output sharpening using Lightroom export. This all works fine.

Now I would like to prepare images for a book. This book will be printed on a HEIDELBERG offset press using coated paper sheets.

The press input will be a PDF file exported with InDesign, using a CMYK color profile (actually ISO COATED V2) as well as a resolution of 300 ppi.

Now I am a little unsure about the right workflow for the book preparation. I am aiming at maximum sharpness for the my RGB images. Is the following workflow adequate?

(1) Do usual stuff in Lightroom / Photoshop
(2) Export the image in Lightroom
    -  using the exact width & height in centimeters as required by the InDesign Layout
    -  with resolution 300 ppi
    -  and this output sharpening: "Sharpen for: Glossy Paper", "Amount: Standard"
(3) Open this image in Photoshop , convert to color profile ISO Coated V2
(4) Place the image in InDesign at the appropriate location
(5) Export the book as PDF in InDesign (no color profile change since all images are already in CMYK)

Does this make sense?

Is there a special sharpening procedure for CMYK images?

Thanks.

Manfred

H iManfred,
I work a lot with cmyk images that end up in books or manuals that I design and produce. Your procedure is fine, with some exceptions.

If I use photographs that I have made, I start in LR, just like you do, and once I am happy with the image I "edit a copy in PS" (not an export)
For images provided by clients, I go straight to PS.
In PS, I make all the changes that are required for the final photo that is to be used in InDesign:
Image size -- exact final size is important for the sharpening step
Duplicate image
Soft-proof with the cmyk profile your printer sends you, or the standard swop
Adjustment layer for unsharp mask
-- and here, I learned the sharpening technique from Image Sharpening by Fraser and Schewe (pages 274-275):
for typical 150 line halftone, coated paper:set the Luminosity of the layer to 60%, Blend if (gray) 10/30 and 230/250; sharpening amount 132, Radius 1.5, Threshold 0. For uncoated paper, the authors recommend an Amount of 158.
Save layered file
Flatten layers
Image mode: cmyk
Save the cmyk file, it is now ready to go into InDesign

In earlier days, I followed recommendations from an Agfa manual, but I have found that the information in the Fraser/Schewe book has given me, and my clients, very good results. There may well be newer information on the best technique for preparing files for offset printing, but this one works for me.

There is a 'but': Heidelberg -- and other press manufacturers -- no longer means just offset, they also make 'digital ' presses (photocopiers on steroids) that do not use halftone screening. For this typeof printing, I pretty much sharpen as i do for my Epson printing.

In any case, getting a copy of  Image Sharpening (the new editions are by Schewe) would be a good investment.

Hope this helps.

Jean-Michel