Don’t Fall into this DPI Rabbit Hole when Printing Your Photos
One of my in-laws emailed me the other day and asked this: When iPhones sync their photos through iCloud Photo Library and then to the ‘Photos’ Mac app… is the resolution maintained? The big concern was whether Apple’s automatic digital file copying to iCloud wasn’t somehow cheating by transferring lower resolution copies.
Because when it comes time to print your photos, you’d want to be sure to have access to the full-resolution versions, right?
The answer is yes. Full resolution, baby!
Apple explains it right here.
Does DPI make a Difference when Exporting a Photo File?
As it turns out, I usually transfer pictures off of my iPhone to do photo management without the iCloud Photo Library ecosystem. I take them directly to Adobe Lightroom via USB along with the pics from my Panasonic Lumix LX10.
So I decided to do a little experiment with iCloud…
I have iCloud Photo Library activated on my iPhone as something of a default. So, I clicked on one of my iPhone’s synced photos on my iMac using the Photos app. Then, I exported the pic to check out its specs.
Yep… it had the same pixel dimensions as its duplicate that I also exported from Lightroom.
I noticed that there was one difference between the two photo files when I compared the specs via ‘Inspector’…
The picture from the Photos app had a 72 Image DPI value, while the sister file from Lightroom displayed a 300 Image DPI value.
So, were these two photo files the same or not?
The Fine Print on DPI
DPI stands for dots per inch and is relevant when you’re printing out a photo. It’s a piece of information that tells a printer how high a quality to print at.
I’ve typically exported my photo files from Lightroom at 72 PPI (pixels per inch) for web use and 300 PPI for a full resolution copy when I want to print it.
(PPI and DPI are related, and many use 300 DPI as a printing standard.)
And while you always should print your photos at 300 DPI (if you can) to maintain its printed quality, the fact that your photo file has 300 DPI in its metadata has absolutely nothing to do with the quality of the photo file itself.
What’s important is the pixel dimensions of the photo. The more pixels the better!
(Newer iPhone pics are 4,032 x 3,024 pixels.)
So, when the Photos app inserts 72 DPI into the metadata of its exported photo files, that’s actually meaningless to the quality of the digital photo files.
But will the 72 DPI setting affect the quality of a printed photo?
This is the center of some ongoing controversy out there. I found this blog post by Dara Skolnick, who did a really nice job explaining the facts and misperceptions about DPI.
But to cut to the chase… the simple answer is no.
If you’re only trying to print out a 4×6, 5×7 or even an 8×10 photo using the photo file’s original pixel count, it shouldn’t matter what the DPI is set to. Your computer and printer will still jam all of the megapixels into your photo, ensuring its quality.
But things will get trickier if you want to create a wicked-large print. That’s when the DPI issue comes into play. If you want to maintain a 300 DPI print quality, there will be a limit to the size of the photo you can print. (Remember, your photo file has a finite number of pixels.)
Yes, at lower DPI numbers, you’ll be able to print larger… but you’ll also begin to sacrifice image quality.
Another important detail to remember is you don’t have to print at the DPI number embedded in the file. Many folks out there say it’s just a meaningless piece of metadata. You can always change the DPI setting when printing…
The bottom line is there’s nothing wrong with simply exporting a file at 300 DPI. But there’s also no real difference when the same photo shows up with a 72 DPI setting.
(As long as the pixel dimensions are the same)
When DPI Does Matter
If you’re planning on sending your files to a professional photo shop to print out huge prints, then DPI can become an important factor.
Otherwise, if you’re like me printing out a few family pics on the home printer, I think you can pretty much forget about DPI.
72 DPI and the Web
And is 72 DPI the right setting for web photos?
Apparently that’s also irrelevant. That number is more of a holdover from the old days.
Let’s move on…
It’s Safe to Print
So, do yourself a favor and don’t fall down the DPI rabbit hole like I just did while researching the facts for this post.
Feel free to print out as many standard-sized photos from your iCloud Photo Library as you like without worrying about DPI and maintaining image quality…
Your photos will look great!