Got myself a filter, but it spins!

[Andreal]

So after I posted some of my latest shot (which were well critiqued, thankyou all ) I was advised that getting a polarizer might be a good idea. I am happy to say that I am now the proud owner of a Hoya ProDigital Circular Polarizer. Im back out to the bush this weekend but I hvae a question about the filter and that is why does it rotate? It screws in tight but the actual glass is on like a seperate rotating thing. I was under the impression that a polarizer would not need to rotate as it effects the whole image?

Also, being retarded I managed to touch the filter and put a mark on it, what would be best to clean it with (just wanna make sure I dont strip an important coating off or something), I have Isopropyl Alcohol which I use for cleaning various things around the house and I have some stuff called "Liquid Fusion" that i use for cleaning my lens (the only reason I haven't used that yet is because it leaves behind a protective layer and I was again worried that this would interfere with the coatings on the filter).

Thanks for the help so far, you guys are awesome!


PS. Just thought I'd add something else I have been wondering about instead of starting a whole new thread.

I noticed someone mention in a thread below me that a lens hood protects from the rain, which leads me to the question, I can use my camera in the rain? And if so, what kinda rain, like is spitting ok but anything else bad, or could I take it out in torrential rain and be fine (I'm somehow doubting this but it would help to know for sure )

Thanks again!

 

[EOS_JD]

So after I posted some of my latest shot (which were well critiqued, thankyou all ) I was advised that getting a polarizer might be a good idea. I am happy to say that I am now the proud owner of a Hoya ProDigital Circular Polarizer. Im back out to the bush this weekend but I hvae a question about the filter and that is why does it rotate? It screws in tight but the actual glass is on like a seperate rotating thing. I was under the impression that a polarizer would not need to rotate as it effects the whole image?

Also, being retarded I managed to touch the filter and put a mark on it, what would be best to clean it with (just wanna make sure I dont strip an important coating off or something), I have Isopropyl Alcohol which I use for cleaning various things around the house and I have some stuff called "Liquid Fusion" that i use for cleaning my lens (the only reason I haven't used that yet is because it leaves behind a protective layer and I was again worried that this would interfere with the coatings on the filter).

Thanks for the help so far, you guys are awesome!


PS. Just thought I'd add something else I have been wondering about instead of starting a whole new thread.

I noticed someone mention in a thread below me that a lens hood protects from the rain, which leads me to the question, I can use my camera in the rain? And if so, what kinda rain, like is spitting ok but anything else bad, or could I take it out in torrential rain and be fine (I'm somehow doubting this but it would help to know for sure )

Thanks again!

Look through the viewfinder as you turn the filter.

Regards using your camera in the rain, I'd avoid it. the hood only stops the drops getting on the front of the lens. your camera has many joints including the one between the lens and camera itself which are not waterproof (unless you have a 1 series camera and a weather proof lens combo).

Put your camera in a protective cover or a plastic bag with holes in it for your eye and fingers to protect it in the rain if you need to.

 

[Jon, The Elder]

Thats the whole idea behind the circular polarizer ! As you rotate the filter back and forth, you change the angle and degree of polarization. A lens hood is not practical when using a filter like this, you can't easily rotate the filter.

As to rain.....use common sense. If it is more than a passing sprinkle, you aren't going to stay shooting very long anyway.

 

[WDodd]

I have the same filter, good choice! :thumbup: Keep in mind that the filter works best at a 90 degree angle from the sun too.

I dunno about anyone else but I clean my filters with a microfiber lens cloth. I rarely use any liquid on it. Occasionally I will use my shirt if its clean and 100% cotton.

 

[ANDS!]

Hmmm, I thought this thread was a declaration that the OP had "spinnaz" on his camera. . .

 

[mmphoto]

http://www.edbergphoto.com/pages/Tip-polarizers.html

 

[Iron Flatline]

Just wipe your filter with the one of those cloths that comes with sunglasses, or your t-shirt. You'll be fine.

 

[jwkwd]

They are almost like mini-blinds, that are half closed. If you can imagine standing in front of a window with the mini-blinds partially closed, there is a point where you can see through them as you raise or lower while looking out. I know it sounds way out there, but in a very basic way, that's how they work. Needless to say, as you rotate the filter that is in front of the lens, you are blocking out light from certain directions.

 

[DSLR noob]

Polarized glass is glass with billions of tiny parallel lines (I don't know how circular ones work with circles) designed to cancel out light frequencies at certain angles. Polarized driving glasses have lines perpendicular to the ground because vertical frequencies get absorbed by black pavement but the horizontal waves hit the road at such and angle you get a reflection (ever seen a "shiny" looking road). These horizontal light waves are then filtered out by little verticle planes (the lines) and your eye sees nothing. Well say your filter has these little lines (or circles on them), yo have to rotate them to cancel out light heading from different directions, specifically reflections. If the light is reflecting off of water horizontally, you want verticle orientation to filter it and see through the water, if it reflecting off of the side of a window, you want horizontal filtration. Point is, it is supposed to rotate and removes different kinds of reflection and will make skys and water more vibrant due to the reflective properties of the molecules in each.

 

[Garbz]

Hmmm, I thought this thread was a declaration that the OP had "spinnaz" on his camera. . .

No they only go on cheap P&S. It apparently makes them act like SLRs

DSLR Noob's explanation while accurate doesn't help much without understanding how EM waves travel. If the physics interests you have a look at http://en.wikipedia.org/wiki/Polarization

The circular polariser works like the linear one but the exiting light has a circular polarisation which does not effect the autofocus on the camera. You can confirm this easily if you have two. Set them up in the correct orientation on top of each other and rotate one and you should get no light through on a certain angle. But place them back to back so the circular elements are together and no amount of rotating will block all the light.

 

[RacePhoto]

I've never seen a polarizing filter that didn't have a dot on it at the "top" when the lines are running straight horizontal. (or bottom, for those living in Australia)

Then you can use this to align the filter, if you wish.

 

[three_eyed_otter]

(or bottom, for those living in Australia)

Funny....

have a good one
3Eo