in OS X, Reviews

Gemini: The Duplicate File Hunter

Over time, in any computer system, it is extremely common to start having duplicate files. I know, I know, you may think that duplicates aren’t that big of a problem. I mean, how often do you deliberately download a duplicate file? If you run a duplicate finder, such as Gemini by MacPaw, you may very well be surprised how many duplicates are hogging up space on your hard drive.
As I have reported recently, I had my hard drive replaced on my iMac due to a recall issue. To prepare for this, I wanted to ensure everything was backed up to my Drobo before handing it over to Apple for the transplant. After a few hours of Googlin’ around the net, I decided to drop the $9.99 on Gemini and test MacPaw’s claim that Gemini is “A totally new and compelling way to locate duplicates and eliminate them from your Mac.”

As you can see from the video above, Gemini has a very nice Apple friendly user interface right from the get go. It doesn’t get much more simple than an add button and a scan button. And that is where will start.

The Search

In the next screen you can see that I added my “Downloads” folder and clicked the scan button. Because I have kept this directory pretty trim it finished quickly, but previously I have run this again directories with over 200 Gigabytes of data and it finished its scan in a matter of minutes. Needless to say, the scan speed is impressive even when I ran it against my USB connected Drobo external hard drive.



The Selection

Once the search is complete, Gemini will display a list of all file types on the left. In the middle you can see the actually file names that were found to be duplicated. Then consuming almost 50 percent of the right side real estate is the details showing all of the duplicate files and their corresponding directories. From here you can individually select files, or use Gemini’s built in “Auto Select” feature. I found this auto select to work reasonably well, although at times it would not select all of the files I wanted. Regardless if you use the auto select or select the files manually, I would not move forward with removal of duplicates until you have reviewed each of your selections one last time.



The Removal

Having selected all of your duplicate files, the last task is to click the “Remove Selected” button and let Gemini do its work. This, as you might imagine, is a bit nerve racking as you watch the shredding animation while your files are deleted. Once deleted, your are presented with a cheery messaged congratulating you on the removal of your duplicates. Gemini thinks so much of this event in fact, it offers to let you tweet your accomplishment right from this screen.


Digging Deeper: Preferences

As far as additional options, there aren’t many, but let’s take a look at the few that are there. Starting off on the first of three preferences screens, the most interesting setting on the general tab is “Move Duplicates to Trash.” This setting is tells Gemini that when it removes your duplicate files to move the to the trash. This is handy, just in case you need to restore something, you get one last chance to review what it is you have deleted.


On the second tab we see a very simple, but in my mind powerful feature. Here you can exclude files from its duplicate searches not just by directory, but also by file names, and file extensions. So, as a developer I have at times found a need to look for certain files, but want to ignore specific file types. Here I could define a file extension of “.html” so gemini will not do its duplicate check on any of my html pages.


The last preferences tab allows you to define inclusion or exclusions from the auto select process we ran earlier. This too is another great feature as in my scenario above, maybe I do want to include html files in my duplicate search. However when I use the auto select, I don’t want it to select an html file for removal from the directory called “web.” This feature is a welcome addition to help make an auto select option that much more powerful and reliable.


If you noticed above in the file removal screen I have a “Total Saved” of over 430 Gigabytes. This was largely thanks to a huge number of photo directories that I worked through with Gemini. It handled all of it with little to no problem even on my USB connected Drobo external drive. I have to admit, even with Gemini doing so much of the heavy lifting, there were times of just straight tedious work to get through all of my files. I shudder to think how difficult the task would have been without a tool like Gemini.

The Question:

So, is it worth the $9.99 if you are only going to use it on the rare occasion? I would have to answer that question with a question; what is your time worth to you? Gemini itself is an attractive, usable, stable piece of software that I see as well worth the money from a product quality perspective. As something that really should become part of a regular maintenance plan, eradicating duplicates on a regular basis just makes sense. As long as you use the tool with care, with an eye towards double and triple checking, Gemini will deliver in spades even if you are trying to sort through a ton of files. That is why I am glad to have it in my maintenance arsenal.

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