How To Clean 35mm Slides: The Complete Guide

How To Clean 35mm Slides: The Complete Guide

We all have that one box in the garage or attic filled with old slides, photos, and negatives from back in the day. For many of us, these images are irreplaceable memories captured as a byproduct of older technologies. 

Unfortunately, these slides often sit in boxes for years or decades until someone decides to dig them up and bring them back into the light. This is where things can get scary. When you open those boxes, you’ll find that some, if not all of those images are entirely coated in dust! Others may have mold and mildew growing on them from sitting in a humid environment, and others will have pieces of lint and other debris stuck to them because of less-than-ideal storage conditions.

Unless you want to keep them locked away and degrading forever, cleaning your slides is the first step toward preserving them for the future. After all, if you leave them as they are now, they may not last for too much longer!  This blog post will walk you through everything you need to know about how to safely clean your old 35mm slides, negatives, and photos.

What You’ll Need

  • Can of compressed air
  • Microfiber cloth or cotton pads
  • Gloves
  • Alcohol-based film cleaner

Option 1: Blow away dust with compressed air

This is the easiest way to clean your slides. All you’ll need is a can of compressed air which you can find at any office supply store, and a pair of gloves to avoid getting fingerprints on any of your images. 

Before you start blowing air in every direction, you might want to do this step in a location you don’t mind getting a little messy. That compressed air will shoot dust everywhere, and you don’t want it contaminating any dust-sensitive items in your home, or floating around in a highly trafficked area.

Remove the slides from their containers and blow off each with a can of compressed air. If dust is still present, more short bursts of air can be used. Avoid holding the slide too close to the can, as this can damage them. A good distance would be anywhere from 5 to 8 inches away.

Option 2: Gently wipe down each slide with a microfiber cloth

Be careful with this method. While wiping slides down with a microfiber cloth may yield better results than compressed air, you’ll want to be as gentle as possible. Consider using a microfiber cloth that’s designed specifically for cleaning delicate items. You can find these at any store that sells cleaning supplies. 

While wearing gloves, gently wipe down each slide with the cloth. You may need to do this a few times each to get rid of the dust or lint that may be stuck to the slides. Be gentle while doing this. You don’t want to scratch or damage the film on the slides. Don’t scrub or press down too hard while wiping them down as this can cause scratches. Use compressed air after to get rid of any cloth particles that may be left behind.

Option 3: Clean the slides with an alcohol-based film cleaner

If you have really dirty slides, you can use an alcohol-based cleaner to gently clean away tough, sticky substances like dirt, grime, mildew, and years’ worth of dust.

Be sure you’re using a cleanser specifically designed for cleaning slides, photos, or negatives. Don’t just use soap and water as this can easily damage your images. Here is a link to where you can find some slide film cleaners. Use the cleaner on both sides of the slide, then let them air dry for a few minutes before putting them back into their storage containers.


After you have finished cleaning your slides and photos, it is time to think about what to do with them. Although they can be returned to the dark closet you found them in, this is generally not a safe idea if you’re worried about preserving these memories. The best thing you can do is convert your slides to digital images. This allows you to save, view, and share your images from all of your modern digital devices such as smartphones, computers, and tablets while protecting them from any physical damage or deterioration.