January 23, 2006

Convert to Grayscale

OK, so it's an ugly topic to discuss because it seems really silly that we're in our 12th version of Illustratordom and yet we still have no easy or reliable way to convert ALL objects in a file to grayscale. But that's what blogs like this are all about. We get to discuss the ugly stuff. What you'll get from today's post is a way to convert an entire document to grayscale (yes -- gradients, patterns, and even meshes too), but with a disclaimer. It still is pretty ugly under the hood, but when you gotta get something out the door under deadline, we tend to think less about the technical shallowness of our deeds, and more about the praise we get for delivering our work on time, on budget, and with the results we expect.

In order to participate in today's class, you will need:

- One copy of Adobe Illustrator CS2
- One copy of Adobe Acrobat Professional
- One Illustrator file (preferably with colored gradients, patterns, and meshes for best effect)

First, open your file in Illustrator and save the file as a PDF file. You can toss the AI portion of the file by unchecking the Preserve Illustrator Editing Capabilities option.

Next, open the PDF file in Acrobat Professional. Choose Tools > Print Production > Convert Colors.

In the Convert Colors dialog, choose Device CMYK: Convert (or RGB is that's what kind of file you created) and for the action, choose Convert. For the Destination Space, choose Gamma 1.8 (it's all the way at the bottom of the list). For Conversion Options, choose the Don't Embed Profile setting. Click OK to perform the conversion.

Save the PDF file and quit Acrobat.

Now for the best part. Open the PDF in Illustrator. First, you'll notice that the patterns are preserved and if you'd like, you can choose to expand them. You'll notice that gradients appear in Illustrator as Non-Native Art objects (we'll talk about these in a future post). But here's what I found. Select the gradient (er, the non-native art object) and choose Object > Flatten Transparency. Click OK in the dialog (the Medium Resolution setting will be fine), and you'll notice that the gradient is now an editable gradient. Yay!

The caveat is that when you reopen the PDF into Illustrator, you'll lose editability (live effects, TEXT, etc.). So what I do is copy and paste the grayscale gradients and patterns back into my original Illustrator document, where the text and other effects are still live. But at least my gradients and patterns are grayscale, editable, and retain their vector heritage.

8 comments:

Wes Rand said...

Hopefully this is one of those areas Adobe can borrow from Freehand to improve Illustrator.

Teri Pettit said...

If there are only a limited number of gradient and pattern filled objects in the file, here is another trick that can be used to completely desaturate the patterns and gradients while keeping them live. It won't convert them to grayscale objects, but it will convert them to process (CMYK or RGB) gray objects in the same tints of gray that would be generated by Convert to Grayscale if those colors were not in a pattern or gradient. (Note, by the way, that the Convert Color filters do work on gradient meshes and embedded rasters).

Select any set of objects that you want to convert to gray that are all on the same layer and contiguous in the stacking order. (The process will move all the converted objects together in the stacking order, so if your gradient-filled or pattern-filled objects are intermingled with other things, it won't be a practical method unless it is OK to select and convert those other things as well.)

Shift-click on the New Symbol button at the bottom of the Symbol palette to define a new symbol and replace the selection with an instance of that symbol.

Set your fill color to be a 50% gray. (It must be 50% to get the same gray tints as Convert to Grayscale would.)

With the Symbol Stainer tool, mouse down over your symbol instance and hold until it stops changing color.

Now click on the Break Link to Symbol button.

Your objects will return to normal, with the patterns and gradients fully desaturated.

Jean-Claude said...

It's always amaze me to see their more than one way to do differents task in Illustrator...

Here another way to convert to grayscale i have use a few time in the past with success. This involve the use of Transparency Opacity Mask

- Draw a square that cover all your art
- Paint it 100% Grayscale
- Select all your art (but not the square) and Cut it
- Select the black square
- Open the Transparency Palette
- Make an opacity Mask and Check the option to Invert the Mask
- Now Click/Target the second thumbnail atthe right
- Paste your art
- Click back the left thumbnail

Voila... easy, accurate Grayscale convertion!

John Kallios said...

I made a action to convert color gradients to grayscale which Kurt was kind enough to host when a portion of this topic was brought up in the Illustrator forum.

http://www.illustrator.hilfdirselbst.ch/Sonstiges/John_Kallios/Gray_gradient.zip

Note: The action requires a named "black" swatch to be in the swatch palette. Changing the action to colorize it to 100% black from the color palette will make the action more robust. (I just never gotten around to doing it)

Note: When flatten transparency is used on a closed path, it becomes a open path.

John Kallios said...

Hopefully this link works for the grayscale action.

John Austin said...

Try using Filters > Color filters > Adjust colors (Sorry, not sure if these are the absolutely correct names in English; I have a German version).
Set to greyscale and be sure to click "Convert" on.
Then patterns, at least, DO get converted!

Chris Clark said...

based on Jean-Claude's comment, i found a new and super easy way to convert the entire document to grayscale. just create a rectangle, color it white, and resize it so that it covers all your art. in the Transparency window, set the blending mode to "color". done, instant grayscale! you can even put this white rectangle on its own layer so you can turn it on and off easily when printing a proof. (I know this forum is old, but the lack of a grayscale output feature still is a problem in 2011, using illustrator CS5 and Adobe Acrobat Pro).

Sergey said...

Chris, you are right about problems with grayscale in 2011. Thank you for your idea!
Is there any javascipts to automate this?