Hoya CPL f/stops reduction

[caresma]

Hi guys,

I just bougth a HOYA CPL 77m for my Canon 10-22.
I noticed it introduces almost 3 stops of light reduction, it sound a little too much to me, I would like to hear some experience on that and understand if it is normal.

Cheers

 

[Garbz]

Look through it man. It's dark grey. All polarisers working on the same fundamental principle have the same inherent insertion loss.

Also f/stop reduction and loss of light transmission are two inherently different aspects. The polariser has no relation what so ever to the f/stops (lens aperture).

 

[caresma]

Hello Garbz,

You did not answer my question. I make it more clear, without CPL I make a shot at 1/200 sec, with the CPL I need to make it a 1/30, then the CPL introduces almost 3 stops (stopping around 85% of the light). Again, it sounds too much to me.

 

[Big Mike]

The amount of light that is blocked by the polarizing filter, will depend on the position (rotation) of the front element of the filter and the amount of polarized reflection in your scene.

Sometimes it might be as high as 3 stops, maybe sometimes it's only 1.5 stops. It's also likely that some of the loss will be over the whole scene and some areas will have more loss....so your metering mode may be playing a factor as well.

 

[KmH]

Hi guys,

I just bougth a HOYA CPL 77m for my Canon 10-22.
I noticed it introduces almost 3 stops of light reduction, it sound a little too much to me, I would like to hear some experience on that and understand if it is normal.

Cheers

Hello Garbz,

You did not answer my question.

You didn't actually ask a question.

 

[caresma]

right, I did not ask a question ;-), just some experience

well, I sent an email to Hoya, they say never heard of a CPL cutting 3 f/stops. THey suggested to send it back to them. I will make some more shot to try and see how it goes

cheers

 

[Garbz]

You said:

I would like to hear some experience on that and understand if it is normal.

I said:

Look through it man. It's dark grey. All polarisers working on the same fundamental principle have the same inherent insertion loss.

As much as I understood what you said to be a question, you should understand what I said to be your answer.

Polarisers have insertion loss. The Hoya $5/hour service centre employee is an idiot if he's never heard of this. All polarisers based on the same principle have the same level of insertion loss. Your camera filter is just as dark as those cheaparse 3D glasses you get at the cinema. Look at it. It's grey. You can't expect to put it infront of your lens and not kill 2+ stops of light on the way through.

A 2-3 stop insertion loss is perfectly normal for a polariser. See It's grey:

 

[caresma]

Garbz, you are really a funny guy and carry on reporting trivial facts, everybody knows the CPL have a filter factor, it usually variate between (1 2/3) to 2, and it's what I got with a previous CPL on a Sigma 17-70. 3 f/stops are too many, as the Hoya guy who replied to me confirmed ( he is a Product Manager and not a $5/hour service as you obnoxiously suggested, then rising the doubt of whom is the idiot over here) . My CPL is behaving almost like a ND8, when it should be more similar to a ND4. Hoya sells a more expensive filter class HD (HOYA FILTERS - The Difference is Clear )., that has a higher light transmission (PS. keep you loved term “insertion loss” for telecommunications topics).
I was looking for some experiences on the real f/stops reduction using a standard Hoya CPL and not for some Oz-pub style explanation. To conclude, I am wondering if you have ever used a CPL in your life or you are just able to find a picture on Google Images to show it to us, wooooww, it's grey!!! Really? You are such a genius!

 

[KmH]

Garbz, you are really a funny guy and carry on reporting trivial facts, ....I was looking for some experiences on the real f/stops reduction using a standard Hoya CPL and not for some Oz-pub style explanation. To conclude, I am wondering if you have ever used a CPL in your life or you are just able to find a picture on Google Images to show it to us, wooooww, it's grey!!! Really? You are such a genius!

Your post has been reported to TPF forum management.

The above portions of your reply were totally uncalled for.

 

[Garbz]

Caresma if you don't want advice don't ask for it. Also if you want a more advanced reply than "it's grey" try to sound less braindead when asking the question.

"Insertion loss" is a term used quite extensively in the fields of electro magnetics, physics and photonics to describe the losses caused by something inserted to the field. Interestingly enough light is an EM field, and switches used in optical fibre by the telecommunications industry are polarisers.

But since you're too busy slagging rather than having a civilised conversation may I ask you please stop ignorantly using the word f/stops. An f/stop is the number used to describe the effective aperture of the lens. The word you are after is exposure value or quite simply "stops"

Anyway you're right and have spoken. The Hoya marketing seems to work far better for you than physics. In which case may I recommend getting a Hoya Pro1D series of filters. They are designed for digital and will work soooo much better because we wouldn't want to use filters designed for film cameras now would we.


In case you want to ask something in the future you won't hear from me. Welcome to my ignore list. You're one of only 4 people with a ****house attitude who have made it on in the last 5 years. Go drown yourself in a beer :cheers:

 

[caresma]

in your reply there was neither physics nor experience but just trivialities, happy to be in your ignore list.