My Magnetic Filter Experiment

[StevenAunan]

After having problems with one of my traditional lens caps, I bought a 77mm magnetic Kase Cap and Inlaid Ring. I like it a lot, but I haven't tried it in the field. @ShipleyNW has the Kase filter system and expressed disappointment in the "holding power of the cap." See https://rfshooters.com/threads/what...-you-bought-or-sold-this-week.2548/post-34424

"The magnet is plenty strong enough for holding filters while they're actively in use, but banging the lens around, in and out of bags, places where you'd want a lens cap, the magnetic cap falls off easier than my Canon spring caps."

That's good information.

I have priced out caps/rings from Kase, Haida, Urth, Nisi, K&F, PolarPro, Freewell, and Maven. Replacing the caps on all my major lenses (67mm x 3, 72mm x 1, 77mm x 4) would cost $245 (Kase) to $500 (Maven or Urth). I'm not spending that amount of money if I can't be sure of the results.

However, Maven makes an Extra Strength adapter ring that claims "increased magnetic holding power." See https://mavenfilters.com/product/extra-strength-adapter-rings/

Could I mix low-cost caps from Kase and high-strength rings from Maven? My cost: $375.

I asked Grok: "Do photographic filter manufacturers publish the polarity of their magnetic filter systems?"

A: No. But users report that Kase, K&F, Haida, Urth, Maven, and NiSi JetMag appear to be compatible, and Freewell is incompatible with the others. See https://x.com/i/grok/share/d11d90e1fafe4322b5dbff460e271392

So last night I purchased one Extra Strength 77mm ring from Maven, and I will test it with the one Kase cap I already have. I'll report back here on the results.

 

[ShipleyNW]

So last night I purchased one Extra Strength 77mm ring from Maven, and I will test it with the one Kase cap I already have. I'll report back here on the results.

I'd definitely be interested in how that works out.

 

[THXGEEK]

I'd definitely be interested in how that works out.

+1

Steven, thanks so much for your research - I look forward to your findings! I simply do not have enough time (between working full time and caring for my 88-year-old Mom) to dedicate to my hobbies. Very much appreciated!

 

[Bryan Conner]

After having problems with one of my traditional lens caps, I bought a 77mm magnetic Kase Cap and Inlaid Ring. I like it a lot, but I haven't tried it in the field. @ShipleyNW has the Kase filter system and expressed disappointment in the "holding power of the cap." See https://rfshooters.com/threads/what...-you-bought-or-sold-this-week.2548/post-34424

That's good information.

I have priced out caps/rings from Kase, Haida, Urth, Nisi, K&F, PolarPro, Freewell, and Maven. Replacing the caps on all my major lenses (67mm x 3, 72mm x 1, 77mm x 4) would cost $245 (Kase) to $500 (Maven or Urth). I'm not spending that amount of money if I can't be sure of the results.

However, Maven makes an Extra Strength adapter ring that claims "increased magnetic holding power." See https://mavenfilters.com/product/extra-strength-adapter-rings/

Could I mix low-cost caps from Kase and high-strength rings from Maven? My cost: $375.

I asked Grok: "Do photographic filter manufacturers publish the polarity of their magnetic filter systems?"

A: No. But users report that Kase, K&F, Haida, Urth, Maven, and NiSi JetMag appear to be compatible, and Freewell is incompatible with the others. See https://x.com/i/grok/share/d11d90e1fafe4322b5dbff460e271392

So last night I purchased one Extra Strength 77mm ring from Maven, and I will test it with the one Kase cap I already have. I'll report back here on the results.

Kase Wolverine magnetic filters are compatible with Urth and K&F. I have something from each of those three in my filter arsenal. But, I bought a Kase Revolution magnetic filter and it is NOT compatible. The physical dimensions cause it not work properly, I can't remember exactly what the issue was, but I had to return it. The polarity of the magnet was correct, just the design itself wasn't compatible.
I wish Maven filters were available here in the EU, I wanted to buy something and shipping was 31€ ( about $36) for a single item.

 

[ShipleyNW]

Kase Wolverine magnetic filters are compatible with Urth and K&F. I have something from each of those three in my filter arsenal. But, I bought a Kase Revolution magnetic filter and it is NOT compatible. The physical dimensions cause it not work properly, I can't remember exactly what the issue was, but I had to return it. The polarity of the magnet was correct, just the design itself wasn't compatible.
I wish Maven filters were available here in the EU, I wanted to buy something and shipping was 31€ ( about $36) for a single item.

Now that you mention it, I think I bought a Kase Wolverine adapter ring (or some piece of Kase Wolverine gear) and it made for a sloppy fit with my Kase Revolution filters. Still, I'd be interested what Steven finds out about that Maven adapter.

 

[StevenAunan]

I received the Maven Extra Strength magnetic adapter today and compared it to the Kase Inlaid adapter. The magnets themselves are compatible.

Get the Maven.

The Kase is very slim and has only a few threads. The Pentax 35mm lens threads are also quite shallow, and the magnetic filter pulls the adapter right off the lens. That does not happen on the Canon 24-105L because it had deeper threads.

The Maven adapter is strong enough that I can manually pull the 24-105 lens all the way to 105mm zoom without detaching the magnetic filter. The Kase adapter magnet is significantly weaker, and the filter can be pulled off the lens with very little effort.

The RF 24-105 exhibits no vignetting with either adapter.

Kase on the left, Maven on the right.

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[ShipleyNW]

Get the Maven.

I might have to give that a try.

 

[StevenAunan]

I have a K&F magnetic adapter on the way. Will compare that next.