Open any old family photo album and you will see it — images that were once sharp and vivid, now washed out, yellowed, or spotted with strange marks. It happens to every photo eventually. But why?

Understanding what causes photos to deteriorate is the first step toward saving them. And the good news is that even badly faded photos are not necessarily lost. There is more information hiding in those faded images than you might think.

The Enemy Is Light (And Time, And Everything Else)

The short answer to "why do photos fade" is: chemistry. A photograph is not a permanent object. It is a collection of chemical compounds sitting on a piece of paper, and those compounds are slowly reacting with the world around them every single day.

The three biggest enemies are ultraviolet light, moisture, and acidic materials. Each one attacks your photos in a different way, and they often work together.

Let us start with the most common culprit.

Ultraviolet Light: The Silent Destroyer

Every photograph — whether it is a daguerreotype from 1850 or a drugstore print from 1995 — contains light-sensitive compounds. That is how they were made in the first place. Light hit the film, caused a chemical reaction, and created the image.

The problem is that the reaction does not stop after the photo is developed. Ultraviolet light continues to break down the image-forming compounds over time. In traditional black-and-white prints, tiny particles of metallic silver create the dark areas of the image. UV exposure gradually converts that silver into silver sulfide, which is lighter in color. The darks get less dark. Contrast fades. Details disappear.

For color photos, the situation is even worse. Color prints use organic dyes — cyan, magenta, and yellow — layered together to create the full spectrum. These dyes break down at different rates when exposed to UV. Magenta tends to be the most stable, which is why old color photos often shift toward a pinkish or reddish cast. The cyan and yellow fade first, leaving magenta behind.

That is why your aunt's 1970s vacation photos all look like they were taken on Mars.

Acid Migration: The Rot From Within

Even if you keep your photos in total darkness, they can still deteriorate. The culprit is often the paper itself.

Most paper manufactured before the 1980s contains lignin, a naturally occurring compound in wood. Over time, lignin breaks down and produces acids. Those acids attack the photo emulsion from behind — literally eating through the image from the back of the print.

This is why photos stored in old cardboard boxes often fare worse than photos kept in albums with acid-free pages. The cardboard is full of lignin, and the acids migrate directly into anything it touches. You have probably seen this as brown spots or an overall yellowish cast.

But it gets worse. Many albums from the 1960s through 1980s used so-called "magnetic" pages — those sticky sheets with a plastic overlay. These pages contain PVC (polyvinyl chloride), which releases hydrochloric acid as it ages. Photos stuck to magnetic pages are literally being dissolved by the album designed to protect them.

If you have photos in a magnetic album right now, removing them should be a priority.

Humidity and Fungal Growth

Moisture is a photograph's other great enemy. High humidity — anything above 65% relative humidity on a consistent basis — creates conditions where fungi and mold can colonize the gelatin layer of a photograph.

Gelatin is an animal protein, and to a fungus, it is food. Mold growth typically appears as fuzzy spots or web-like patterns on the photo surface. In advanced cases, the fungal colonies actually digest the gelatin, leaving permanent pits and holes in the image.

Basements and attics — the two most common places people store old photos — are also the two worst environments for them. Basements are damp. Attics cycle between extreme heat and cold, creating condensation. Neither is a good home for anything you want to keep.

Different Photo Types, Different Vulnerabilities

Not all photographs deteriorate the same way. The type of photo matters enormously.

Daguerreotypes (1840s-1860s)

The earliest practical photographs, daguerreotypes are images on silver-coated copper plates. They are surprisingly durable in some ways — the metallic silver image does not fade like paper prints. But they are extremely vulnerable to tarnishing. Exposure to sulfur compounds in the air creates a hazy, iridescent film over the image.

If you find one unsealed in a drawer, do not try to clean it yourself. The image sits on the surface and can be wiped away with a single careless touch.

Tintypes (1860s-1920s)

Tintypes are images on thin iron plates coated with a dark lacquer. They are physically tough — they do not crack like glass plates and they handle being stored in boxes better than paper prints. Their main enemy is rust. If the lacquer coating chips or cracks, moisture reaches the iron and the photo literally rusts from within.

Kodachrome Slides (1935-2010)

Kodachrome is famous for its longevity, and that reputation is well-deserved. The dyes in Kodachrome are fundamentally different from other color processes — they are embedded during development rather than present in the film from the start. This makes them remarkably resistant to fading.

Well-stored Kodachrome slides from the 1950s can still look nearly perfect today. Poorly stored ones will show the same magenta shift as other color photos, just more slowly.

Polaroid Instant Photos (1948-present)

Polaroids are among the most vulnerable photos you will encounter. The chemical process that creates a Polaroid image never fully stabilizes. The reagent layer continues to react for years, causing progressive color shifts, fading, and eventually a uniform brownish-yellow cast.

If you have Polaroids from the 1960s-1970s, digitizing them soon is strongly recommended.

Modern Inkjet Prints (1990s-present)

Many consumer inkjet inks are not lightfast at all. A framed inkjet print in a sunny room can fade noticeably in as little as two to three years. If you have important photos printed on a home inkjet, the originals should be backed up digitally.

How to Slow the Fading

You cannot stop deterioration entirely, but you can slow it dramatically.

Control the environment. Store photos in a cool, dry, dark place. Ideal conditions are 65-70°F (18-21°C) and 30-40% relative humidity. A bedroom closet on the main floor of your home is usually better than the attic or basement.

Use acid-free materials. If you store photos in boxes, use acid-free archival boxes. If you use albums, choose ones with acid-free pages and photo corners rather than adhesive mounts. Never use magnetic albums.

Handle with care. Oils from your skin accelerate deterioration. If you are handling original prints, clean cotton gloves are not overkill — they are standard practice in every archive and museum.

Keep photos out of direct light. If you want to display an original photo, use UV-filtering glass in the frame. Better yet, display a high-quality reproduction and keep the original safely stored.

Separate problem materials. Old newspaper clippings, rubber bands, and paperclips are all enemies of photographs. Newspaper is extremely acidic. Rubber releases sulfur. Paperclips rust. Remove all of these from your photo collection.

The Digital Safety Net

Even with perfect storage, physical photos will continue to deteriorate. Slowly, but inevitably. The single most important thing you can do for any photo collection is create high-quality digital scans.

A good scan captures the image as it exists right now — before it fades any further. That digital file will not deteriorate. It can be backed up, shared, and reproduced indefinitely.

And here is where it gets interesting: once a photo is digitized, AI colorization tools like PhotoRevive can go a step further. They do not just preserve the faded image — they can restore color and detail that has been lost, giving you a version of the photo closer to what it looked like when it was originally taken.

For black-and-white photos, colorization adds a dimension that was never captured in the first place. For faded color photos, AI can analyze what remains of the original color data and reconstruct what has been lost. Either way, you end up with something more vivid and more alive than the deteriorating original.

It Is Not Too Late

If you are reading this and thinking about a box of photos in your closet that you have been meaning to deal with — the time is now. Not next month. Not next year. Every day those photos sit in suboptimal conditions, they lose a little more.

The process does not have to be overwhelming. Start with the photos that matter most. Scan them. Store the originals properly. And if you want to see what they looked like before time did its work, bring color back into the picture.

The chemistry of deterioration is relentless, but it is not the end of the story. Your family photos have survived this long for a reason.

The best time to save an old photo was twenty years ago. The second best time is today.