It’s a frustration that all photographers on the Canon RF platform have experienced. Maybe you’re on a location shoot, or maybe you’re in a studio environment—it always goes down the same way.  You don’t have the right lens on your camera for the shot you want, so you need to quickly change lenses. You remove the lens that’s on your camera, grab the one you need, and get it mounted.  The clock is ticking. The shooting conditions are changing with each passing second.

You grab the dust cap to put it on the lens you just removed. On it goes…Tick tock.  You start twisting and turning the dust cap, trying to get it to lock into place—but it’s just not happening.

Then you remember: Unlike the old EF lens caps, Canon’s original RF dust caps must be lined up in one very specific orientation to properly attach to the lens.

Now you’re hunting for the alignment mark on the dust cap and the red mark on the lens. Finally, you find them, line everything up, twist the cap into place and…

The dust cap is now on.  But you’ve missed the shot.  Gone. Finito. Hope is lost.

Okay, that reenactment might be a tad on the dramatic side. But those stupid dust caps can be frustrating enough to make a preacher cuss.

Enter the Canon Lens Dust Cap RF II

Canon announced a redesigned dust cap earlier this year <que the angel chorus>.  The new Lens Dust Cap RF II (retail price:  $8.99) was announced on May 13, 2026 – nearly eight years after introducing the RF mount and its notoriously finicky original rear lens cap. The redesigned cap began reaching customers in July.

Demand has been strong, making availability spotty since they were introduced, but I was able to order four from B&H Photo in August (and for only $8.00 each)—here’s a close-up of the box:

When the new dust caps arrived, I quickly popped one out of the box – the logo side of the caps were virtually identical.  Same color, texturing, knurling, and even the same alignment marker.  But when I put the new version II dust cap on a lens, it worked magically compared to the previous version.  I could put the new cap on virtually any old way and get it to thread on properly.  Put the new lens cap on with one hand?  No problem.  Put the new lens cap on while not looking at the lens?  No problem!  The new Lens Dust Cap RF II essentially worked just like the old EF mount lens dust caps.

WHAT CHANGED?

Above is a side by side photo of the version I and version II lens cap.  The biggest change appears to be a tab that’s against the interior wall on version one which is absent on version II.  There’s also a tab that’s present on both versions but slightly shorter on version II than version I:

Why Canon didn’t go with this version II design from the start, I have no idea.  Many people grab and hold their lenses by the dust cap – maybe they went with the version I design because it’s deemed more secure/less prone to come off?

CAN VERSION I BE MODIFIED?

Since I had four version I dust caps that no longer had much value, I decided to try some red neck engineering to make a version I dust cap function like a version II.  I simply got out a pocket knife (a Dremel would likely work well too) and went to work on the tab present on version I that was absent on version II.  Here’s a photo of my handy work:

It’s not pretty…you risk injury (is saving $8 really worth your medical deductible if you cut yourself and need stitches?) and the modified cap doesn’t feel quite as nice on a lens as version II.  But…it works.    Without that tab, a version I dust cap can be put on an RF lens in about any orientation and doesn’t have to be perfectly aligned to the markers on the cap and lens.  It probably took me about 20 minutes of cutting.  If you do attempt this, make certain you thoroughly clean the dust cap before putting it on the back of a lens.  You don’t want plastic fragments scratching up your lens or making it into the sensor of your camera.

Is the Canon Lens Dust Cap RF II Worth The Upgrade?

Absolutely – particularly for the pro photographer.  Or for the easily annoyed amateur.  The new lens dust cap design removes friction and frustration and improves the overall shooting experience.  Priceless.