Smaller photo file size, without changing the date

May 4, 2015 12:22 AM

Is there any way to resize photos without changing the date on the file?

I don't need 6Mb files for my holiday shots, but I don't want to forget when they were taken. I'm on a Mac, if that's relevant.

Yes I have thought about buying extra storage.

posted by superfish to Technology (6 answers total)

EXIF date or filesystem date (from right-click, Get Info)?

In either case, the answer is yes, because both dates can be edited.
posted by ryanrs at 12:27 AM on May 4, 2015

Doesn't EXIF data typically have three dates for photos? Date modified and date created which (barring steps taken to prevent it) would change when you reduced the file size and another is "data taken" which should not change.
posted by If only I had a penguin... at 8:00 AM on May 4, 2015

Pretty much any proper photo tool that does bulk operations (Lightroom, Photo Mechanic, etc.) can transform the images without losing the EXIF timestamps. If you're worried about it, make a copy of a handful of them, run the resize on those, and see what happens.

That said, unless you have hundreds of thousands of photos, it's hard to imagine this saving enough space to be worth it since storage is so incredibly cheap these days. Also, keep in mind that photos which seem unimportant now can be important in the future. For example, what if one of those holiday photos ended up being a treasured photo of a family member or friend who passed away? It's hard to know ahead of time which photos will be special, and I speak from experience when I say that it's a massive bummer to suddenly want a high quality print of something, and have only a low-res file of it (in my case it happened when a family member economized on memory card space by putting their camera in low-res mode, and ended up unknowingly capturing the last days of a beloved pet with small overcompressed jpegs).

Even if you can't fit all the full sized-photos on your computer, you should seriously consider backing them up somewhere. For about $50 you can store over 150k 6MB images.
posted by primethyme at 9:19 AM on May 4, 2015

There is an app for OS X called Graphics Converter. It can read the date from the photo's exif data and write that to the file's creation and modification date.
posted by conrad53 at 1:45 PM on May 4, 2015

To answer your specific question: Yes, you can resize photos and preserve the date. Most competent photo manipulation programs (even Preview on OS X) will save the File Creation date and alter only the File Modification date. Try it and see - I just did.

But in almost all cases, this is a bad idea. JPEG image compression degrades your file irreversibly - if there is any chance at all that you will care about a given image, you will regret compressing your only copy. And if there is no chance that you will ever care about it, why are you saving it?

I would recommend:

(a) A good weeding - delete anything that is blurry or pointless or duplicative, and keep maybe 50% at best. Also, star or favorite the best 10% so that you can find them later.

(b) Storage is cheap. For still images, a couple of 1TB external disks will cost you $100 (see primethyme's link above, for example) and give you plenty of room to store and back up photos. Videos chew space. Photos, not so much.
posted by RedOrGreen at 2:36 PM on May 4, 2015

I don't want to forget when they were taken
You could always change the file names to include the date taken.
posted by soelo at 11:18 AM on May 6, 2015