Beware magnetic filters

[mercurius]

I recently bought a couple of Urth magnetic filters (a CP and a ND64) for the Tamron 28-200mm lens on my Sony A7CII. Yesterday was the first time I tried either of them (the CP) doing a walk around a local historic garden. Half way through the session I suddenly realised that the filter was missing and must have dropped off somewhere. Needless to say I coudn't find it.

This has really put me off magnetic filters and I am definitely going back to the screw-on ones.

Any recommendations for good quality screw-on CP and ND64 filters?

 

[THXGEEK]

I am partial to Hoya filters. For your Tamron, the HRT would be a good fit. On a budget? The Tiffen is well-rated.

I haven't used it, but the Hoya ProND EX ND should work for you.

 

[rcreamer]

I recently bought a couple of Urth magnetic filters (a CP and a ND64) for the Tamron 28-200mm lens on my Sony A7CII. Yesterday was the first time I tried either of them (the CP) doing a walk around a local historic garden. Half way through the session I suddenly realised that the filter was missing and must have dropped off somewhere. Needless to say I coudn't find it.

This has really put me off magnetic filters and I am definitely going back to the screw-on ones.

Any recommendations for good quality screw-on CP and ND64 filters?

I have Breakthrough filters. I haven't used them enough to be able to comment on their performance. Important things to research about filters are: 1) vignetting, and 2) no color shift (primarily for NDs).

 

[Richard A]

I have a dozen or more Maven magnetic filters. They have pretty strong magnets. I use them often - last time just last week. I have never had a problem with them falling off. They are definitely more user friendly than screw on ones. Have you heard of anyone else having a similar problem with the Urth filters?

BTW, if you are using a mirrorless camera, you can use a Linear Polariser rather than a Circular one. Generally, Linear Polarisers have less of a colour cast.

 

[Unframed Dave]

I use K and F magnetic, if anything, they're a pain to pull off, especially when the lens hood limits grip on them.

 

[Richard A]

I use K and F magnetic, if anything, they're a pain to pull off, especially when the lens hood limits grip on them.

That can be true but no more of a pain than unscrewing a filter in the same situation...

 

[Unframed Dave]

True enough.

 

[evacguy]

That can be true but no more of a pain than unscrewing a filter in the same situation...

I also use Maven magnetic filters - the Linear Polariser is always on my 70-200mm f2.8. I also have the magnetic lens cap. I've had these for a long time, must be at least two years. These magnets are very strong and I've never had the LP or lens cap just fall off, but I have noted a couple of annoying issues:
1) The lens cap is difficult to take off, it is definitely a two hand job. If I use just one hand, I tend to pull off the LP and the lens cap. I have to use my second hand to keep the filter on and pry off the lens cap. And even this is not trivial. Definitely not a quick process. It was extremely annoying at first, but I'm use to it now.
2) When I take my camera with 70-200mm f2.8 lens attached out of my sling bag, I need to be a little careful as it is a snug fit. If I'm not careful, the filter and lens cap comes off, usually within the bag, but sometimes its fallen onto the ground.

Not sure if a screw in LP filter would be better. If you need to change filters often, I think the magnetic filters (assuming they have good magnets) would be better, but if you rarely change filters, perhaps a screw in one would be better.