polarizer for canon S45

[shacks]

Hi all

I currently have a S45 and am very happy with it, however I have recently purchased a circ. polararizing filter for my SLR and like the effect it has on some photos.

Is it possible to purchase a circ. polarizer filter for the S45, how much is it and where is the best place to buy it? I am currently in Australia so any local(ish) web sites would be great.

Many thanks

Paul

[juno]

if you already have a circular polarizer, you dont need to purchase another one for your s45. that one will just work fine with your s45.

what you should be more concerned of is finding a lens adapter for your s45. i have seen some custombuilt adapters for the s-series being offered over the net, but i cannot remember the site. try doing a search on "lens adapter for s45".

[juno]

hey, here's the link to the lens adapter:

http://www.ckcpower.com/s3040.htm

and should you have a different thread size for your existing filters, all you need to get is either a step up or a stepping down ring. you dont need to buy two sets of filters for each of your cameras.

and here's the thread which you may find interesting >> http://photography-on-the.net/forum/showthread.php?t=3549

[ganeg]

hi guys i just received the ckcpower adaptor for the s45 last week and have used a hoya 37mm uv filter and a kenko 37mm polarizer. one question, i have noticed that the polarizer makes some images look a bit "flat" not too sure how to describe it, someone told me about adjusting the polarizer, how do i do that?

[juno]

ganeg,
you must be using a linear polarizer. linear polarizers can be adjusted by rotating it until you get the desired effect while mounted on the lens adapter. Circular polarizers works best with AF cameras.

[ganeg]

thnx for the tip juno, i am using the kenko circular 37mm polarizer and now attempting to adjust the thingy, each time i adjust i would take a shot and notice that it makes certain parts of the image darker. is this normal?

[juno]

photos getting darker when using polarizers are normal especially when taking shots indoors. the reason for this is that polarizers prevents a certain amount of light to pass thru the filter at a certain angle and that probably is that part where your photos seem darker.

for me, the best place and time to use the polarizers is when the sun is up, and you want to take more of the colors you see around than the glare you get from it (example : light being bounced from the water when taking sunset shots over a body of water). it is like wearing your sunglasses on a hot sunny day.

[stopbath]

ganeg wrote:
thnx for the tip juno, i am using the kenko circular 37mm polarizer and now attempting to adjust the thingy, each time i adjust i would take a shot and notice that it makes certain parts of the image darker. is this normal?

You are likely shooting in wide angle and seeing the sky go from deep blue to a lighter blue.

The polarizer works best when light is coming in at a certain angle. The effect lessens as the angles change and since wide angle lenses encompase a wide angle of view, the polarizer is more effective in only one portion of the sky.

Zoom in to eliminate this (since you will have smaller spreed of angles.)

[Branislav]

Linear and circular polfilter have the same effect on picture itself. Both of them pass through light that happen to be polarised in one plane, and stop the rest - more or less, depending of choosen filter.

Reflecting of non metal surfaces, refraction, and passing through certain crystals polarises light (more or less). Polarisation depends on angle of reflection and/or reflection, diffrerent for each material. When polarisation is maximal, angle of reflection/refraction is called "Brewster's" angle - he defined relation between refraction coefficient and "strenght" of polarisation for any material that reflects/refracts light.

On photograph darkest part of sky is one that is angled from Sun at Brewster's angle, from the point of photographer.

Difference between circular and linear polfilter is important ONLY if metering system in camera is polarised itself. If it is (due to the various light reflections, refractions etc.) circular polfilter is needed. If it is not - linear will do.

Poin is that linear polfilter and polarised metering system may cause error - if you turn polaroid filter in certain angle (to achieve desired) effect, and it happen to be 90 degree of polarising plane of metering system, poor camera will think it is very dark, even it is not!

Both linear and circular polfilter filter the light the same way, but once filtered, light leaves linear filter still polarised, and circular filter rotates planes of polarisation (of light leaving filter), so light have quality like it never have been polarised. Thats why it is called circular. That is mandatory for some types of cameras.

If you don't know if your camera have polarised metering system, and you still did not buy circular, you can put linear polfilter in front of camera (lens, of course ;o) ), measure light of plane wall on example. Than you rotate the filter. If you notice strong changes in measured light, metering system is polarised, and you need circular. In not, you can buy linear, that should be cheaper. It is important in this experiment that you measure light of some non polarising surface - simple wall, strait in front of you (`90 degrees) will do.

Besides this, there is no difference between circular and linear filter.

And at last - you should by all means rotate your filter before you make photograph to acive desired effect - you can not know at what angle will light come when you leave home with your camera nad filter attached - that's why polfilters are made the way they can be rotated. Rotate, see the effect, and then take picture!

[Branislav]

Sorry.

I just saw usefull link given by stopbath on "Polorizing filter use and LCD hoods in A70" topic.

http://www.cliffshade.com/dpfwiw/polarizer.htm