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.

 

[rcreamer]

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.

You mentioned you use a linear polariser/polarizer. I have been frustrated for years that scenes look better through my polarized (LP) sunglasses vs my circular polarizer camera filters. Lately I've been thinking maybe buying an LP filter. How do you like the LP vs the CP? Thanks in advance.

Update: it looks like the only difference between LP and CP is a slight change that helps with autofocus and exposure. So, LP probably won't make much if any of a difference.