Experience Scanning with Acrobat 9 on a Mac

Question

Friends asked for a copy of a 4-page document we'd used in a study group.  I'll just scan it in with Acrobat!  Then we have the benefits of its being electronic.  Plus it'll give me a chance to try out Acrobat 9, which I just got, and scanning on my Mac (on Windows until recently).
Why it took me an hour to scan the document:
Acrobat can assemble a PDF file from scanned pages and OCR it.  I'll just scan in this four page doc and send it out as PDF.  Simple, right?
Bring up the Acrobat panel to Create PDF From Scanner, and it says to select a scanner.  There are none on the list.  Hmm.
When I set up my Mac a few weeks ago I tested and was able to scan.  Maybe it's because my printer/scanner is now plugged in via TimeCapsule rather than directly as before.  Can my Mac see it?  How do I know?  Can it see the printer device--perhaps both printer and scanner don't come online at the same time.  Bring up Sys Prefs, it shows a green light by the TimeCapsule-connected printer.  Ah, but it did that yesterday even though it could NOT print to it.  Bring up the Print Queue for that printer and click Utility.   ...scanning for printers...found none.  Do I believe that?  Try printing to it.  It works.  Finding none doesn't mean it isn't working.
Try plugging the printer/scanner directly into the Mac.  No difference.
Follow the "maybe scan is different from printing" thought.  Where is the System Prefs for Scan/Fax?  Doesn't seem to be one.  Maybe it's just TWAIN drivers.  How was it I tested scanning initially?  Search [Finder] for scanner.  Nothing obvious.  Futz around a bit.  Ah, it was Image Capture.
Image Capture CAN see the scanner.  So I could scan in by hand to separate files and assemble in Acrobat.  Sure would be easier if Acrobat had control of the scanner as it [presumably] knows more about what it needs re scan settings.  Search Internet for problem.  Aha, found it on the third hit.  The Epson TWAIN (scan) driver must not be Universal binary.  Acrobat sees only Mac Universal binaries.
Check Adobe documentation to see if there's a way around this.  None found.  They don't even acknowledge the Universal binary requirement when talking about Mac.
So, scan separate pages using Image Capture.  Ahh.  The document's printed on really thin paper so type from the back side is bleeding through, badly.  How can I adjust the contrast on the scanner to compensate?  Nothing obvious.  What if I tell Image Capture it's Text?  No, that just seems to change Bit Depth to 1.  Changing it back to 8 causes the Document type to be Photo.  Well, at least there's a setting for B&W Photo.
Scan to TIFF files (the default).  Go into Acrobat and create a PDF from the four TIFFs.  Run OCR.  Hmm.  Still looks awful because of bleed through in image--OCR just adds invisible (selectable, searchable) text on top, without discarding image--and file size is rather large.  It's good enough, but now I'm curious as I've had better results with this in the past with Acrobat 8 on Windows, though it's been so long I can't remember exactly how.
Back to the Internet to read about OCR in Acrobat 9.  Ahh.  I think they phased out the previous method I used and replaced it with "ClearScan", a new technology which creates Type 3 approximation fonts on the fly and places those visible on top with the scanned image, greatly compressed (and de-skewed) underneath.  They recommend scanning at 300 dpi (I'd used whatever the default was, 150 I think).
OK.  Try scanning again.  Set to 300 dpi.  Hmm.  Must be SOME way to change the contrast to correct the bleed through.  Ahh.  It's set to "Image Correction: None".  I'd missed that before--my bad.  Try "Manual".  I get a control panel.  No contrast but I can affect brightness separately in Dark, Midtones, and Light.  Turning up Light does it.  Scan all the pages again.  Bleed through is gone (as seen in Preview windows that pop up).
Go into Acrobat and recreate the PDF from the TIFFs.  Well, it won't let me see the files.  I scanned them into /tmp.  (I've set up a symlink of /tmp to /FinderVisibleRoot/tmp (along with other hidden / dirs).)  tmp is greyed out though not others in that dir.  Futz around a bit trying other operations which open a file panel, come back, and now tmp's not greyed out.  Sigh.
Create the PDF from the TIFFs.  Looks exactly like before, bleed through and all.  WTF?  Check the TIFFs in Preview--as expected; no bleed through.  Perhaps something got cached.  Close and restart Acrobat and try again.  Same result.
The Image Capture adjustment to Brightness must not have changed the actual scan but some meta data stored in the TIFF. ??
Where can I tell Acrobat to honor that?  There are no options when I open files to be combined to create the PDF.  "Try again, Luke."   Nope.
Let's try just one file at a time with Create PDF From File.  Same problem.  The files panel for opening those files DOES have a Settings... button, but it's greyed out.  It's set to "All Types", which includes TIFF.  What if I change it to just TIFF?  AHA!!  Now the Settings... button is active.  Not obvious to me (I get why, given multiple types could be selected, but my gosh).
Now I can control how Acrobat changes the incoming TIFFs (I'm guessing PDF doesn't support TIFF directly so converts to JPEG, CCITT, etc.).  Not exactly sure how conversion works so futz with a few of what I imagine are the obvious options.  No effect.  Hmm.
Ah.  Maybe Image Capture (or the driver) is actually creating a color profile to affect the image adjustments I made, and embedding that in the TIFF.  Can color profiles be put in TIFFs?  I didn't think so.  Turns out they can.  And retaining embedded profiles was turned on in the conversion settings by default for all image types EXCEPT greyscale. :-)  Turn it on for greyscale and try again.  Voila!
OK.  Go back to Merge Files Into Single PDF to do all the pages.  Oops.  There's no Settings... option where I can tell it to keep the embedded profiles.  Sigh.  Use Create PDF From File for each page then merge those.
Now run OCR with ClearScan on the resulting PDF, and keep only very low resolution of original scan.  Result is a small (196K for 4 pg), clean looking, fully searchable document!
The on-the-fly Type 3 fonts it created aren't great (flaws visible when zoomed).  I think an older technology we had at Adobe of trying to match scanned chars to available fonts stands a better chance for high fidelity (and this may still be avail in a non-ClearScan option).  However, I still like the new ClearScan technology for some uses like this, where fidelity isn't such an issue.
Hopefully, the Universal binary problem on Mac with Acrobat will go away at some point (when I get a new printer? ) so I'll just be able to scan directly into PDF.  And Adobe will need to add Settings for Merge Files Into A Single PDF to control color profile handling, etc.
Thanks to all the Adobe forum folk whose posts informed me for this task.
--Dan

Answer 1

When I posted the message, it showed me "More Like This" with some relevant threads.  Relevance was pretty cool.
I read there are Acrobat app-wide conversion settings for importing different file types.  If I set Preferences/Convert To PDF/TIFF settings, it affects files specified to Merge Files Into A Single PDF.  It's still inconsistent that I specify it one way for Create PDF From File and another for Merge Files Into A Single PDF, but at least it can be done.