Cheap polarizing filter @ 200 mm - impressively bad

[shoffmeister]

So the Panasonic 100-300 has a front filter diameter of 67 mm, and I wanted to try a polarizing filter on that. Just for laughs.

Running into an "Andoer Digital Filter HQ High Quality CPL 67 mm" on a Chinese trading web site at USD 5 provided an excellent opportunity - I simply added to the batch of dirt cheap mechanical goods that I wanted.

Well, it somewhat unsurprisingly turns out that 5 USD might be a tad bit too low, given that a Marumi Exus CPL 67mm sells at USD 100 (http://www.amazon.com/Marumi-Antistatic-Filter-Circular-Polarizer/dp/B00CCZ40DO)

Below I have posted two photos, shot within seconds of each other, of my innocent test subject - a leaf in autumn. The Andoer filter "performance" represented there is very much representative of what to expect: A horrible mess. At 300mm (600mm equivalent) shot into the distance (leaves again) the problems are even much more pronounced.

The interesting question now is: What is the minimal price for at least some good quality?


No polarizing filter




Andoer polarizing filter in place

 

[cameron2]

To some extent, filters represent a "you get what you pay for" trade-off. Some people are perfectly happy with Tiffen or whatever for $20; some like Hoya for $30-50; others won't use anything less than B+W or Heliopan for $100+.

I would suggest avoiding anything from a brand that you don't know. No-name junk is worth less than $0, so getting it for free is a rip-off, and paying for it does nothing except fund the destruction of the environment.

Also, as an aside, and with respect to polarizers, you are supposed to be able to use a linear polarizer with mirrorless cameras; most polarizers are circular, because DSLRs can't use linear polarizers.

 

[dmanthree]

Looks like camera shake, even at 1/500 may be an issue here. Hard to believe even a cheap filter could be that bad.

 

[Skeeterbytes]

Linear polas work fine on our cameras and cost less of a light loss hit. But in my search I can't find multicoated or coated linears so if one wants a coated pola, it seems to be circular or nothing.

Cheers,

Rick

 

[tt321]

Looks like camera shake, even at 1/500 may be an issue here. Hard to believe even a cheap filter could be that bad.

 

[shoffmeister]

Looks like camera shake, even at 1/500 may be an issue here. Hard to believe even a cheap filter could be that bad.

My thoughts exactly when I first tried the filter.

It is that bad, even at high(er) shutter speeds; I tried quite a few targets.

 

[Fri13]

Of course as it follows the magnification rule.

Some people use cheap filters and then blame all filters to lower the image quality, in every possible situation.

 

[Paulmorgan]

My last 67mm PL filter cost me about £70, some will see this as cheap

 

[Frasier Krane]

So the Panasonic 100-300 has a front filter diameter of 67 mm, and I wanted to try a polarizing filter on that. Just for laughs.

Running into an "Andoer Digital Filter HQ High Quality CPL 67 mm" on a Chinese trading web site at USD 5 provided an excellent opportunity - I simply added to the batch of dirt cheap mechanical goods that I wanted.

Well, it somewhat unsurprisingly turns out that 5 USD might be a tad bit too low, given that a Marumi Exus CPL 67mm sells at USD 100 (http://www.amazon.com/Marumi-Antistatic-Filter-Circular-Polarizer/dp/B00CCZ40DO)

Below I have posted two photos, shot within seconds of each other, of my innocent test subject - a leaf in autumn. The Andoer filter "performance" represented there is very much representative of what to expect: A horrible mess. At 300mm (600mm equivalent) shot into the distance (leaves again) the problems are even much more pronounced.

The interesting question now is: What is the minimal price for at least some good quality?


No polarizing filter


Andoer polarizing filter in place

In my experience, this is quite common. And you don't even have to have a cheap, uncoated one to experience this. I had a brand name CPol that was coated and I experienced something similar at telephoto FL's. At wide angles it was fine.

Many of these just aren't built to a high enough standard to handle long FL's. That's where imperfections in the glass will usually show up.

The weird thing is that the lens manufacturers can put in 10 to 20 elements into a relatively cheap lens that all work perfectly together.

Yet, these filter manufacturers have a hard time putting together a single piece of flat glass that doesn't screw up lens performance.

My suggestion would be to look at the old lenstip.com tests for CPols. Even though it was 2009, the high scoring ones should still be okay. The good ones won't have this problem. You should make sure that you get a multi-coated filter.

 

[Hen3ry]

In my experience, this is quite common. And you don't even have to have a cheap, uncoated one to experience this. I had a brand name CPol that was coated and I experienced something similar at telephoto FL's. At wide angles it was fine.

Many of these just aren't built to a high enough standard to handle long FL's. That's where imperfections in the glass will usually show up.

That's odd, I would have thought the long focal lengths would be okay but shorter focal lengths, e.g. with w/a lenses, would be more susceptible to faults.

 

[Paulmorgan]

So the Panasonic 100-300 has a front filter diameter of 67 mm, and I wanted to try a polarizing filter on that. Just for laughs.

Running into an "Andoer Digital Filter HQ High Quality CPL 67 mm" on a Chinese trading web site at USD 5 provided an excellent opportunity - I simply added to the batch of dirt cheap mechanical goods that I wanted.

Well, it somewhat unsurprisingly turns out that 5 USD might be a tad bit too low, given that a Marumi Exus CPL 67mm sells at USD 100 (http://www.amazon.com/Marumi-Antistatic-Filter-Circular-Polarizer/dp/B00CCZ40DO)

Below I have posted two photos, shot within seconds of each other, of my innocent test subject - a leaf in autumn. The Andoer filter "performance" represented there is very much representative of what to expect: A horrible mess. At 300mm (600mm equivalent) shot into the distance (leaves again) the problems are even much more pronounced.

The interesting question now is: What is the minimal price for at least some good quality?


No polarizing filter


Andoer polarizing filter in place

Its not the filter, its you.

 

[Hen3ry]

…I would suggest camera shake must be a factor.

1/500 is simply too long an exposure for reliable sharpness with a 600mm (equiv) lens. The old rule of thumb for "safe" exposures isn't necessarily right -- particularly when longer lenses at full extension are unbalancing the kit -- although OIS/IBIS should help.

But a really valid comparison would have to be with the camera on a tripod.

 

[Skeeterbytes]

As a SWAG, a pola is probably easier to mess up on manufacture than a simple filter since it's a sandwich of sorts--the filter sheet between glass. Not something that would allow for shortcuts without performance penalties.

Cheers,

Rick

 

[JosephScha]

With IS, 1/500th is NOT too slow a shutter speed for a 300mm lens, even if you (as you claim) we should think of it as a 600mm lens.

Furthermore, the blur does not seem to be in one direction, it seem to be perfectly equally distributed in all directions. That is not what camera shake does.

Now, it could be that the polarizing filter interfered with ability to auto-focus in some way, or perhaps just slowed it and the camera is not set to wait for focus. But I don't think we can attribute any of the blur we see to camera shake.

 

[Paulmorgan]

With IS, 1/500th is NOT too slow a shutter speed for a 300mm lens, even if you (as you claim) we should think of it as a 600mm lens.

This will vary from one person to another.

Furthermore, the blur does not seem to be in one direction, it seem to be perfectly equally distributed in all directions. That is not what camera shake does.

Now, it could be that the polarizing filter interfered with ability to auto-focus in some way, or perhaps just slowed it and the camera is not set to wait for focus. But I don't think we can attribute any of the blur we see to camera shake.

Your test does not tell us a lot, at the mo it just looks like camera shake.

--
js

 

[Paul Amyes]

I've experienced this. Years ago I bought a Canon EF 70-200 f2.8 L and when I got it home I started playing with it. I'd put a Hoya circular polarizing filter on it and was horrified at the results when I checked them on my computer. Thinking I'd got a dud lens I took it back to where I bought it from and explained what had been happening. The guy behind the counter on hearing I'd used a polarizing filter reached under the counter and pulled out a B+W. When I used the results were sharp.

Lesson learnt. There is no point in spending heaps of cash on good lenses and then chucking cheap filters on the front.

 

[Steve_]

Well, it somewhat unsurprisingly turns out that 5 USD might be a tad bit too low, given that a Marumi Exus CPL 67mm sells at USD 100 (http://www.amazon.com/Marumi-Antistatic-Filter-Circular-Polarizer/dp/B00CCZ40DO)

The interesting question now is: What is the minimal price for at least some good quality?

Marumi makes excellent filters, and they are cheap by quality filter standards. Everyone has different perceptions of what is 'good quality', but make no mistake, Marumi makes no bad ones. Their DHG polarizer is of very good quality, and the Super DHG grade is truly excellent. I have not seen their 'Exus' product tested, one would hope they would be as least equal to the well-regarded SDHG grade. I have several DHGs and they are good enough by my standards, as indicated by their test results.

Unfortunately Marumi has some sort of sad joke for distribution in the US, and I can't find a really representative price on the 67mm DHG CPL. I believe this should only be a $55-60 item, but Marumi filters are so hard to come by that in less-popular sizes like 67 those available may have gone through many hands and/or be marked up excessively due to the lack of proper alternative sources.

 

[shoffmeister]

Unfortunately Marumi has some sort of sad joke for distribution in the US, and I can't find a really representative price on the 67mm DHG CPL. I believe this should only be a $55-60 item,

For a fair price (fair as far as geographical price discrimination is concerned) I look at the Japanese price comparison site "Kakaku"; http://kakaku.com/item/K0000505404/?lid=ksearch_kakakuitem_image has the 67mm Exus CPL listed at JPY 9990, roughly USD 85.

Compare that to some seller on ebay.com asking for USD 130 plus shipping out of the UK (which means that they are based in Hong Kong and exploit some UK tax scheme) - http://www.ebay.com/itm/Marumi-67mm-EXUS-Circular-Polarizer-67-mm-Filters-EXS67CIR-/291486111745

 

[Steve_]

Unfortunately Marumi has some sort of sad joke for distribution in the US, and I can't find a really representative price on the 67mm DHG CPL. I believe this should only be a $55-60 item,

For a fair price (fair as far as geographical price discrimination is concerned) I look at the Japanese price comparison site "Kakaku"; http://kakaku.com/item/K0000505404/?lid=ksearch_kakakuitem_image has the 67mm Exus CPL listed at JPY 9990, roughly USD 85.

Yes, that sounds right. With the DHG being two grades less in their marketing scheme it's a 55-60 USD item. I think I paid $54 for the last one I bought in 67mm, but that was 3 years ago.

Compare that to some seller on ebay.com asking for USD 130 plus shipping out of the UK (which means that they are based in Hong Kong and exploit some UK tax scheme) - http://www.ebay.com/itm/Marumi-67mm-EXUS-Circular-Polarizer-67-mm-Filters-EXS67CIR-/291486111745

I guess it's a lot easier to find a bad deal on a Marumi than a good one, world-wide.

 

[Robiro]

It has been already discussed here a few times.

Rule no. 1 for Panasonic 100-300mm: Don't ever attach a CPL filter to it.

It will not focus correctly with it.

It's a feature...

There is nothing wrong with your 100-300mm, mine is doing it too. It would not focus with a CPL.