Is a Circular Polariser Lens Filter worth buying? ...... £30

Submariner Gold

Submariner Gold

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Dash Cam
Vicovation MF3
How many of you guys use these?
Do they make a big difference?

If I had paid > £300 for an all signing and dancing dashcam ... well why not :)

I only paid £79 for my Vico FM3, so is it worth paying £30 for a CPL?

My concern is it might make it too dark at night?

I guess the std. Vico one is technically cheap and nasty ... rubbish, and sadly being 30mm one is very limited in choice.
Stuff I would normally use like a Hoya Pro-1D sadly only goes down to 37mm.

If you experienced users thought a CPL was a good thing to have, then I would prefer to pay £30-40 for a Hoya Pro-1 D in 52mm and get a step up filter converter. At least I could use it on my normal camera lens
 
A CPL filter do block some light, and its not like it make every reflection in the windscreen go away.
So it do also impact night recordings, but not on a level that bother me personally cuz i have a very large perspective on night recordings, and the few little useful things you can get from it, but those little things you can still get with a CPL filter i think.

BUT ! i am using a DIY dashmat instead of a CPL filter, if you can get one for your make/model car that to me are by far the best solution.
 
kamkar1 said:
A CPL filter do block some light, and its not like it make every reflection in the windscreen go away.
So it do also impact night recordings, but not on a level that bother me personally cuz i have a very large perspective on night recordings, and the few little useful things you can get from it, but those little things you can still get with a CPL filter i think.

BUT ! i am using a DIY dashmat instead of a CPL filter, if you can get one for your make/model car that to me are by far the best solution.
Click to expand...

Thanks ........never heard of a Dashmat
I need to do a search lol
 
OK, got to be honest I think that would rather defeat the point of paying for the 'Exclusive Nappa Leather' Upgrade on my car.
I would rather have the reflections or hopefully get the polariser to solve it.
 
Submariner Gold said:
If you experienced users thought a CPL was a good thing to have, then I would prefer to pay £30-40 for a Hoya Pro-1 D in 52mm and get a step up filter converter. At least I could use it on my normal camera lens
Click to expand...
The £30 Hoya wont remove reflections any better than a £3 CPL.
It may be very slightly brighter, but not enough to notice.
The only real difference is that the Hoya will have better anti-reflection coatings so you may get better contrast/colour.

The effectiveness at removing the reflections depends a lot on the car, what is able to reflect in the glass and the angle it reflects at. Since I have a different car to you I can't say how effective it will be, but someone with the same car may know...
 
Nigel said:
The £30 Hoya wont remove reflections any better than a £3 CPL.
It may be very slightly brighter, but not enough to notice.
The only real difference is that the Hoya will have better anti-reflection coatings so you may get better contrast/colour.

The effectiveness at removing the reflections depends a lot on the car, what is able to reflect in the glass and the angle it reflects at. Since I have a different car to you I can't say how effective it will be, but someone with the same car may know...
Click to expand...

Thanks,
I dont have a very ‘popular’ car.
Its a Mercedes S Class Coupe, so that has a more raked or angled down windscreen than say the std. more popular saloon S Class; if that helps.
Not sure if having a “flatter” screen would make the reflections worse than or better.

I get your your point about quality, but if I went the converted Hoya route, then the better colour rendition might be worth it if say I wanted to use it on my pro canon camera.
 
There are a range of ways yo get pro sized filters on little cameras like gopro and so on, same might be used with some mods on a dashcam, but that defeat one of the main goals ( for many of us at least ) and that is to have the dashcam be as stealthy as possible.
A dashcam can no doubt be a reason for things escalating if a idiot find out that he will be forced to own up to his stupid, so best if that kind of people are left not knowing and with a chance of diggin their own grave with lying to police and fraud to his/her insurance company.
 
£30 is THEFT!
 
You don't need a circular polarizer. buy a plain linear polarizer
 
jackalopephoto said:
You don't need a circular polarizer. buy a plain linear polarizer
Click to expand...

How do you tune it ?
Plus any comments on this theory see below
“There are two types of polarizing filters available: linear or circular. Linear polarizers are more effective and less expensive than circular ones. But circular polarizers are needed with just about any camera that has a through-the-lens metering system, or autofocus.

The reason for this is that both of these systems use semi-silvered mirrors to siphon off some of the light coming though the lens. If that light is linearly polarized it renders either the metering or the autofocus ineffective. This means that you're going to have to buy circular polarizers unless you're shooting with a pre-1970's camera, or a view camera.”
 
Last edited:
Submariner Gold said:
How do you tune it ?
Click to expand...
The reflections from the glass and road surface are all horizontally polarised, so you just install it vertical, no need for tuning.
 
+1. There are a number of threads in the DIY forum on pol. filters made from a variety of lens sources. I did one from an old pair of clip-on sunglasses which are (were?) definitely not CPL and it worked just fine. CPLs are needed in SLR cameras that have a mirror for A/F - since dash cams are all fixed focus it's a non-issue.
 
Submariner Gold said:
Plus any comments on this theory see below
“There are two types of polarizing filters available: linear or circular. Linear polarizers are more effective and less expensive than circular ones. But circular polarizers are needed with just about any camera that has a through-the-lens metering system, or autofocus.

The reason for this is that both of these systems use semi-silvered mirrors to siphon off some of the light coming though the lens. If that light is linearly polarized it renders either the metering or the autofocus ineffective. This means that you're going to have to buy circular polarizers unless you're shooting with a pre-1970's camera, or a view camera.”
Click to expand...
That is not quite right, a circular polariser contains a linear polariser and will work equally effectively, the only difference is that it also contains a quarter wave plate which changes the output of the linear polariser to circular polarisation, this will have no visible affect for a fixed focus camera like a dashcam or action camera.
 
Submariner Gold said:
How do you tune it ?
Plus any comments on this theory see below
“There are two types of polarizing filters available: linear or circular. Linear polarizers are more effective and less expensive than circular ones. But circular polarizers are needed with just about any camera that has a through-the-lens metering system, or autofocus.

The reason for this is that both of these systems use semi-silvered mirrors to siphon off some of the light coming though the lens. If that light is linearly polarized it renders either the metering or the autofocus ineffective. This means that you're going to have to buy circular polarizers unless you're shooting with a pre-1970's camera, or a view camera.”
Click to expand...

Circular doesn't refer to the shape, you can rotate any kind of polarizer that's round and screws into a lens. The only type that can't be rotated would be rectangular ones that slide into a slot
 
I made a CPL for my A119 with some self adhesive polarising film off ebay and a small circular watch glass. About £2.00 all in!

Still have enough film for another dozen CPLs!
 
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