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4GB will be enough for iPhoto. I can still run Aperture 2.0 on my late 2010 Macbook Air with 4 GB. I'm glad I upgraded back then from the 2GB though for sure. Mind you, Aperture won't load or run nearly as fast as my new rMBP with 16GB and the super fast SSD but she likely won't notice any lag ;)
 
I saw buying a laptop less than 8GiB of soldered RAM as bad already in 2012.
 
You'll get wildly varying opinions here because everyone uses their computer differently. Some will say you need 8 GB or more because they need it to do heavy RAM intensive work. This is good advice if your usage is similar to theirs, but it may not be.

Others will disagree and say you only need around 2 GB because they only use their machine for word processing and light browsing and never use more than 1 GB. I only use about 200-300 MB out of 1.25 GB on my PowerBook at most, but I would never recommend 1.25 GB to the average user.

The only way to really know how much you need is to look at how much RAM you use doing normal tasks. It's not a perfect estimate because your computer may be wanting to use more RAM than it has, thus making it seem less needy, but it should be a good ballpark figure.

I think 4 GB is enough for a long time for your purposes.
 
You'll get wildly varying opinions here because everyone uses their computer differently. Some will say you need 8 GB or more because they need it to do heavy RAM intensive work. This is good advice if your usage is similar to theirs, but it may not be.

Others will disagree and say you only need around 2 GB because they only use their machine for word processing and light browsing and never use more than 1 GB. I only use about 200-300 MB out of 1.25 GB on my PowerBook at most, but I would never recommend 1.25 GB to the average user.

The only way to really know how much you need is to look at how much RAM you use doing normal tasks. It's not a perfect estimate because your computer may be wanting to use more RAM than it has, thus making it seem less needy, but it should be a good ballpark figure.

I think 4 GB is enough for a long time for your purposes.

I meant I would not buy less than 8GiB of soldered RAM for light use since 2012, seeing that you have to keep that for some years.

Myself, 16GiB is not enough when I'm doing heavy work since last year.

Just Mavericks, Mail, Safari, and Qobuz are using more than 9GiB RAM now (ok, 3GiB file cache)
 
OSX does a great job at memory management, and if you run short you swap out to the SSD - you're incurring a performance penalty but nothing like it was a few years ago when the swap space was on a spinning disk.

Still, if you can get 8GB, its better overall. I'd not buy a 4GB machine now a days - its just too meager.
 
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