This is BrainLog, a blog by Dan Sanderson. Older entries, from October 1999 through September 2010, are preserved for posterity, but are no longer maintained. See the front page and newer entries.

July 10, 2007

I had to do three things to get my old but nice Canon CanoScan N650U flatbed scanner to work with Adobe Photoshop CS3: 1) I had to download the latest driver for this model, which included a Photoshop plugin. 2) I had to manually move the CanoScan Photoshop plugin into /Applications/Adobe Photoshop CS3/Plug-ins. 3) I had to run Photoshop under Rosetta, the PowerPC emulation layer in Mac OS X for Intel Macs, because Canon's drivers do not yet run directly on the Intel hardware.

To run Photoshop under Rosetta, find /Applications/Adobe Photoshop CS3/Adobe Photoshop CS3, right-click (or control-click) on it, select Get Info. In the panel that opens, check the "Open using Rosetta" checkbox. From now on, Photoshop will open under the (slower) Rosetta PowerPC emulator. The loading screen (with the logo and the status messages) will say "Running under Rosetta".


For clarity sake, Rosetta is not an emulator, it is a binary translator. Most people don't care to understand the difference, but for those of us in the industry, there is a big difference. An emulator simulates an entire architecture including hardware, OS, and any app environments. A binary translator only translates code from one CPU architecture to another. It doesn't emulate anything, rather, it performs the real time translation. A common emulator on the Power PC platform was Virtual PC (from Microsoft). That product emulated the entire Intel architecture where you loaded windows, then your application.

I know Rosetta carries overhead, but the overhead is tremendously lower than an emulator would require. Your app should be fairly usable with Rosetta, vs being nearly useless with a fat emulator.

BTW - Rosetta is a product OEM'd from Transitive. I work in the industry and have used their products with other platforms as well.

Thanks for the Rosetta tip. I have the same trusty scanner, and couldn't get it to work in Photoshop on my new intel mac until I found your post.

Thanks for the useful information my friend. Perfectly explained.

Thank you ,this was very clear and easy to follow. I was trying to set up my canoscan N122OU. The scanner now shows up in import in CS3, however I keep getting an error message that the scanner is not connected. I have the scanner plugged directly into the back of the tower. Any suggestions?

thank God there are some helpful people who know what's going on!

i have a macbook pro running tiger, photoshop cs3 and my trusty n650u scanner, i used the installer and fiddled for hours to no avail, until i read this....thank you

THANK YOU. I have spent hours trying to get my CanoScan N650U to work with my CS4 on a Mac 10.5 OS and thanks to this post I finally can!

Thank you, but I have a problem: no box to "open using rosetta."

My iBook runs under 10.4.11 powerpc G4 platform. Is this my problem? How can I get Rosetta?

@mistermilkman: If you have a PowerPC, you won't see the checkbox because you don't need Rosetta. Rosetta is for running PowerPC applications on an Intel chip.

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