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Hi Sandrah,
Just out of curiosity, what is your goal, what are you hoping to achieve?
FWIW, B&W and grayscale are almost synonymous. I say "almost" becuase absolute B&W means that all antialiasing is converted to black as well. This is text at 200% the top one has antialiasing the bottom one is converted to absolute B&W. Are you sure you want that?
The fact that they're telling me Adobe in the 2020s can't do what took 2 clicks for Corel in the mid-90s, and what any scanner can do, is highly suspect.
By @sandrah80731053
Obviously, you do not understand the problem. A scanner scans bitmaps. The operator defines a threshold. What is below that threshold is white (background), what is above is black (foreground). And it's a point on an image file. A PDF holds text and graphics in complex settings, like an ad in a newspaper. Converting that to black and white in the PDF (so not greyscale, which is obviously what black and white television is about!) is contra productive. You will have items not visible when doing so. Or you will need to raster and dither your vector graphics and text, which is counterproductive.
Adobe Acrobat won't offer this.
It is very touching to see "professionals" support each other even when they are wrong... But you seem a little better than Gary, so you confirm that Adobe can't do what Google do for all his books on Google Books ? When Adobe will offer this option ? 2067 ?
By @Cerbo24878402260w
Sure, you can do any transform you want, but may be Acrobat is not the tool you should use for this.
I don't know what “Google does” for all “his” books. What I know is that in my 30+ years of professional services, I've never seen the need to do what has been asked, as this is best done on the output level.
Imagine a text in colour, the colour translate to greyscale: Red nearer to black, orange nearer to white. Now transform that into black and white only at a 50% threshold. The red text will be black, the orange text will be white. Simple. Orange text will disappear.
What I was asking for was if 49% grey is considered white or black, and the same for 51%, 55%, 45% and all values in between 0.0001% and 99.9999%.
That is a legitimate question and proves that probably the OP has asked the wrong question.
Greetings,
It's difficult to understand when we are sure to know everything...
By @Cerbo24878402260w
It's obvious that you do not understand the issue.
What does Google with books? How do they produce “their” Google books? They SCAN old books, as of your saying, in BITMAP and put that into a PDF. I've done that 20 years ago with faxes. Faxes got scanned and transformed into PDF files (by my fax machine) and distributed via e-mail. The transformation was done before converting into PDF. Google does the same: Scan in bitmap→Convert to PDF. When you have a colour or greyscale document, transformation into pixel map (bitmap for true black and white) is best done by the printing device (or the display device). Why? Because the printer's engine best knows the optimal parameters to do that.
So, could I build jumping cars? Yes. Is it useful? No.
Here are the instructions on how to create the Fixup needed for the Preflight profile I shared above:
- In the Profile settings, select Fixups and then click on New Fixup:
- As the name enter "Convert color to B&W"
- As the action select "Convert Colors", under "Color spaces, spot colors, inks".
- Select the following settings:
- Click OK, and then add the newly created fixup to the profile:
Notice there might already be similar one called "Convert color to B/W" (with a "/" instead of an "&"), so make sure to use the right one. The fixup will then appear in the middle column, and the profile can be saved and used on your file!
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